Stratus Multi &
Deck
Installation
Installation and Operations
Operation
Manual
Manual
KW-IOM-8022
May 2014
Part No. 31E08022
Contents
Direct Expansion
HFC Parallel Rack
KW-IOM-8022| Version 01
Warranty and Warranty Policy
Work Authorization Process
for Warranty Labor
General Safety Information
Receiving and Inspection
Lifting, Location and Mounting
of Equipment
Ventilation, Floor and Foundation
Requirements
Vibration and Vibration Isolation
Leak Check (Rack)
Field Electrical
Field Piping
Installation of all Filters and Driers
Refrigerant Line Insulation and Support
Leak Test
System Evacuation
Start-Up Procedure
Superheat
Ongoing Maintenance
Compressor Burnout Cleanup
Procedure
Oil Control System Troubleshooting
Appendix: Charts, Checklists
and Templates
3-5
5-6
7
7
7-8
8
8
9
9
10-12
12
13
14
14
15
16
17
17-18
18-19
20-21
22-27
Installation and Operation Manual
Explanations of system warranty, inspection, installation, operation and maintenance will be found in the following
pages and detail on individual components can be found in the separate component installation manual. This document is intended to provide guidance where customers do not have a specified process guideline. Customer specifications and local codes may take precedence over directions contained in this document. Any practices contrary to
those outlined in this document may lead to poor performance or reliability of the system. Any damage or impact of
noncompliance with these procedures is the responsibility of the customer and/or refrigeration technician.
NOTE: INSTALLATION AND MAINTENANCE TO BE PERFORMED ONLY BY QUALIFIED PERSONNEL WHO
ARE FAMILIAR WITH LOCAL CODES AND REGULATIONS, AND EXPERIENCED WITH THIS TYPE OF EQUIPMENT.
CAUTION: SHARP EDGES AND COIL SURFACES ARE A POTENTIAL INJURY HAZARD. AVOID CONTACT
WITH THEM.
WARNING: THIS EQUIPMENT MAY CONTAIN A SUBSTANCE WHICH HAS BEEN ASSOCIATED WITH GLOBAL
WARMING. VENTING OF CERTAIN REFRIGERANTS TO THE ATMOSPHERE IS ILLEGAL. REFRIGERANT
RECOVERY DEVICES MUST BE USED WHEN INSTALLING OR SERVICING THIS PRODUCT. CONSULT YOUR
LOCAL CODES FOR REQUIREMENTS IN YOUR LOCATION. IT IS ALSO VERY IMPORTANT TO FOLLOW EPA
GREENCHILL LEAK TIGHTNESS GUIDELINES AND LEAK PREVENTION AND REPAIR GUIDELINES.
WARNING: THERE MAY BE MORE THAN ONE SOURCE OF ELECTRICAL CURRENT IN THIS UNIT. DO NOT
SERVICE BEFORE DISCONNECTING ALL POWER SUPPLIES.
WARNING: ALL PERTINENT ELECTRICAL CODES AND REGULATIONS MUST BE STRICTLY FOLLOWED.
ANY DEVIATIONS FROM THESE REQUIREMENTS WILL BE STRICTLY THE RESPONSIBILITY OF THE INSTALLER.
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Direct Expansion HFC Parallel Rack
Standard Warranty
Seller warrants to its direct purchasers that Products, including Service Parts, shall be of a merchantable quality, free
of defects in material or workmanship, under normal use and service for a period of one (1) year from date of original
equipment start-up, or eighteen (18) months from date of shipment by Seller, whichever first occurs. This warranty
runs to only the original purchaser of equipment or part. Any Products covered by this warranty found to Seller’s satisfaction to be defective upon examination at Seller’s factory will at Seller’s option, be repaired or replaced and returned
to Buyer via lowest common carrier FOB seller’s point of shipment. This is buyer’s sole and exclusive remedy and,
except as provided in the next sentence, seller’s sole and exclusive liability in connection with the warranty. Or Seller
may at its option grant Buyer a credit for the purchase price of the defective Product. Buyer must prepay all costs for
transportation of Products to Seller’s factory.
Seller shall have no liability for expenses incurred for repairs made by Buyer except by prior, written authorization.
Any claim under this warranty shall be made to Seller in writing within the warranty period specified above, otherwise
such claim shall be deemed waived. Seller shall have no warranty obligation whatsoever if its products have been
subjected to alteration, misuse, negligence, free chemicals in system, corrosive atmosphere, accident, or if operation is contrary to Seller’s or manufacturer’s recommendations, or if the serial number has been altered, defaced, or
removed.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED TO ANY WARRANTY OF MERCHANTABILITY OR FITNESS, AND ALL OTHER
OBLIGATIONS OR LIABILITIES OF SELLER ARE HEREBY DISCLAIMED.
Warranty Notes
This equipment is designed to operate properly and produce rated capacity when installed in accordance with accepted industry standards. Failure to meet the following conditions may result in voiding of the system warranty:
1. System piping must be installed following industry standards for good piping practices (see details later in this
document).
2. Inert gas (dry nitrogen) must be charged into piping during welding.
3. System must be thoroughly leak checked and evacuated before initial charging. High vacuum gauge capable
of reading microns is mandatory--Dials indicating pressure gauges are not acceptable.
4. Power supply to system must meet the following conditions:
a. Voltage for 208/230 not less than 195 volts or more than 253 volts.
b. All other voltages must not exceed +/- 10% of nameplate ratings.
c. Phase imbalance not to exceed 2%.
5. All controls and safety switch circuits properly connected per wiring diagram.
6. Factory installed wiring must not be changed without written factory approval.
THIS WARRANTY SHALL NOT APPLY:
Glass is not guaranteed against breakage. If this refrigerator is equipped with a glazing assembly carrying the manufacturer’s brand name (Thermopane, Twindow, etc.), the manufacturer’s glazing warranty in effect at the time of this
shipment is extended to that assembly.
1. BULBS: Light bulbs, fluorescent lamp tubes and LEDs are not covered by any warranty for length of life or for
any type of breakage.
2. To the condensing unit used with refrigerated equipment unless same was sold and shipped by Seller
3. When this equipment or any part thereof is damaged by accident, fire, flood, act of God, alteration, abuse,
misuse, tampering, when the original model and serial number plate has been altered, defaced, or removed or
used other than the recommended application by Seller.
4. When this equipment or any part thereof is subject to operation on low, high or improper voltages. Low and high
voltage is defined as more than a 5% drop below or 10% higher than name plate voltage ratings. NOTE: Proper
field supply voltage to the equipment is the responsibility of the owner (end user).
5. To damage caused by overloading shelves or wire racks beyond the specified weight limits. The maximum
weight limit for Seller’s standard shelves and wire racks is 30lbs per square foot.
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Installation and Operation Manual
6. When this equipment or any part thereof is damaged, or when operation is impaired, due to failure to follow
installation manual. NOTE: Proper installation is the responsibility of the installer, owner (end user).
7. Operational issues caused by ambient environmental conditions outside of the specified limits. Seller’s indoor
equipment is specified to operate in a conditioned ambient environment not to exceed 75 degrees Fahrenheit
or 55% relative humidity. NOTE: Providing specified ambient environmental conditions are the responsibility of
the owner (end user).
8. To equipment with final destinations unknown to seller as indicated on the original sales order.
9. To labor cost for repair or replacement of parts.
10. To special or expedited freight or shipping charges or to customs duties to any country.
11. If the Warranty holder fails to comply with all the provisions, terms and conditions of this Warranty.
Parts replaced under this Warranty are warranted only through the remainder of the original Warranty.
Extended Service Agreements are provided by a third party not affiliated with Seller. The services provided by the third
party are subject to the terms and conditions of the Extended Service Agreements and Seller is not responsible for
those services or the third party’s performance of its obligations.
IT IS EXPRESSLY UNDERSTOOD AND AGREED THAT SELLER SHALL NOT BE LIABLE TO BUYER, OR ANY
CUSTOMER OF BUYER, FOR INDIRECT, SPECIAL, INCIDENTAL, CONSEQUENTIAL OR PUNITIVE DAMAGES,
INCLUDING LOSS OF PROFITS, ADDITIONAL LABOR COSTS, LOSS OF REFRIGERANTS OR FOOD PRODUCT,
OR ANY INJURY TO PERSON OR PROPERTY CAUSED BY DEFECTIVE MATERIAL OR PARTS OR FOR ANY
DELAY OR MISPERFORMANCE IN THE PERFORMANCE DUE TO CAUSES BEYOND ITS CONTROL OR FOR
ANY EXPENSES INCURRED BY REASON OF THE USE OR MISUSE BY BUYER OR THIRD PARTIES OF THE
PRODUCTS. SELLER’S MAXIMUM LIABILITY FOR DIRECT DAMAGES IS LIMITED TO THE AMOUNT PAID BY
THE BUYER FOR THE PARTICULAR ITEM OF EQUIPMENT OR PART INVOLVED.
NOTE: IN THE CONSTANT EFFORT TO IMPROVE OUR PRODUCTS, WE RESERVE THE RIGHT TO CHANGE AT
ANY TIME SPECIFICATIONS, DESIGN, OR PRICES WITHOUT INCURRING OBLIGATION.
COMPRESSOR WARRANTY
Compressor replacements or exchanges shall be made through the nearest authorized wholesaler of the compressor
manufacturer (not at Seller’s factory) and no freight shall be allowed for transportation of the compressor to and from the
wholesaler. The replacement compressor shall be identical to the model of the compressor being replaced. Additional
charges which may be incurred throughout the substitution of other than identical replacements are not covered by
this warranty. An optional, non-assignable, three (3) or four (4) year extended compressor warranty may be purchased
within the boundaries of the United States of America, its territories and possessions, and Canada. With this extended
compressor warranty, replacements are administered by an authorized compressor distributor only. Replacements
within the first year of the warranty are available through the distributor; the second through fifth years, the purchaser
must submit a proof-of-purchase of a compressor and supply it to Heatcraft Warranty Claims for reimbursement.
PARTS WARRANTY POLICY
The following procedures are in accordance with the Kysor/Warren standard one-year warranty, which covers any part
to be free of defects under normal use and service for one year from the date of installation. (Not to exceed one year
and 30 days from the date of original shipment from the factory.)
In Warranty/Non-Warranty Parts Replacement
When ordering Warranty replacement part(s), the following information must be furnished to the Parts Department via
phone, or e-mail with purchase orders provided by Fax or e-mail only.
1. Full name and address of Company
2. Name and phone number of person ordering parts
3. Model number
4. Serial number
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Direct Expansion HFC Parallel Rack
5. Factory order number
6. Description of parts desired
7. Original date of installation
8. Reason for replacement
9. Complete shipping address
10. Purchase order number
If the order is for a replacement part still in warranty a Purchase Order Number will be required from the contractor
placing the order. We will then issue a Return Material Authorization Tag (RMA) that will be sent to the firm or contractor
who has ordered the part.
NOTE: ALL WARRANTY REPLACEMENTS ARE SHIPPED PRE-PAID F.O.B. SHIPPING POINT. THE WARRANTY
IN EFFECT FOR PARTS DOES NOT COVER THE COST OF SPECIAL FREIGHT TERMS – I.E. UPS NEXT DAY,
AIR FREIGHT, ETC.
Warranty of Replacement Parts
Parts will be covered for the balance of the manufacturer’s standard equipment warranty or 90 days from the date of
shipment of the replacement part, whichever is longer.
If the order is for a replacement part still in warranty a Purchase Order Number will be required from the contractor
placing the order. We will then issue a Return Material Authorization Tag (RMA) that will be sent to the firm or contractor
who has ordered the part.
NOTE: ALL WARRANTY REPLACEMENTS ARE SHIPPED PRE-PAID F.O.B. SHIPPING POINT. THE WARRANTY
IN EFFECT FOR PARTS DOES NOT COVER THE COST OF SPECIAL FREIGHT TERMS – I.E. UPS NEXT DAY,
AIR FREIGHT, ETC.
Purchase Parts Locally
If you require an emergency Warranty replacement and you have to purchase the parts from a local supply house,
Kysor/Warren will accept the return of the original part for replacement only. Should the locally purchased part(s) fail, it
must be returned to the local supplier for replacement, repair or credit.
Return Authorization Procedure
When in-warranty replacement parts are shipped with the service order stating “warranty replacement, return replaced
material within (45) forty-five days of shipping date or invoice will be rendered and payable” return is required. Credits
will not be issued for parts returned after (45) forty-five days.
WORK AUTHORIZATION PROCESS FOR WARRANTY LABOR
All warranty labor claims must be approved in advance by an authorized Kysor/Warren associate. Note: Only Technical
Support associates and company officers are authorized to approve warranty labor. If labor is approved, the payee will
be issued a written work authorization. All invoices submitted without a written work authorization are subject to denial.
The following information is required before the issuance of a written work authorization:
• Store name
• Store address
• Model number (all involved), Serial number (all involved)
• Complete description of issue and corrections to be made.
• A “Not to exceed” estimate for repairs.
In case of after hour’s emergency, you must contact the Technical Support Department at the beginning of the next
business day. Phone (800) 866-5596. Same info as above is still required.
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Installation and Operation Manual
The written work authorizations must be included with all invoices. Only written authorizations will be considered. E-mail
approvals from authorized Kysor/Warren associates are approved and should be included with invoices.
All invoices containing warranty parts not obtained from Kysor/Warren Service Parts Department must be accompanied
by the wholesaler’s invoice for reimbursement or will be replaced through the Kysor/Warren Service Parts Department.
(Kysor/Warren will pay only wholesale cost of parts if not supplied by Kysor/Warren). All defective parts must be returned
to Kysor/Warren if so requested. (See Parts Warranty Policy)
Labor to change DOA compressors will be paid only with a teardown report from the compressor manufacturer,
submitted with the invoice. (Note: Compressor must be factory defective, as described in teardown report, before labor
will be paid). Teardown reports have to be requested at the time of warranty exchange from an authorized wholesaler.
All model and serial numbers must be included on your invoice, (for all equipment serviced). For compressor warranty,
the model and serial number of the unit the compressor was located and the model and serial number of the compressors
– both old and new – must be included.
All invoices must be billed to Kysor/Warren first party. Kysor/Warren will not pay third party invoices. E-mailed invoices
and scans of backup are preferred and may speed processing.
Invoices submitted after 30 days from date when work was done will be subject to denial. Invoices submitted after 60
days from the date when work was done will be denied.
If you receive a notice requesting more information, (i.e. model, serial number, etc.), you will have an additional 30 days
to respond. If a response is not received within 30 days, the invoice will be denied.
All warranties of the equipment are subject to standard manufacturers warranty and terms and conditions of the sale.
Any exception to the standard warranty policies must be specifically agreed to in writing by Kysor/Warren prior to the
date of sale.
All invoices must be sent to: Kysor/Warren, Attn: Technical Support Coordinator, 5201 Transport Boulevard, Columbus,
GA 31907-8944. Phone (800) 866-5596.
Labor to replace parts damaged in transit (shipping damage) must be noted on the shipping bill before any labor
charges will be considered for payment.
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Direct Expansion HFC Parallel Rack
General Safety Information
1. Installation and maintenance to be performed only by qualified personnel who are familiar with this type of
equipment
2. Units are pressurized with dry air or inert gas.
3. All units must be evacuated before charging the system with refrigerant.
4. Make sure that all field wiring conforms to the requirements of the equipment and all applicable national and
local codes.
5. Avoid contact with sharp edges and coil surfaces. They are a potential injury hazard.
6. Make sure all power sources are disconnected.
WARNING: REFRIGERANT CAN BE HARMFUL IF IT IS INHALED. REFRIGERANT MUST BE USED AND
RECOVERED RESPONSIBLY.
FAILURE TO FOLLOW THIS WARNING MAY RESULT IN PERSONAL INJURY OR DEATH.
Receiving and Inspection
Inspect all equipment and any accessories for damages or shortages before and during unloading. If there is any
damage, the carrier should be notified immediately and an inspection requested. The delivery receipt must be annotated
that the equipment was received damaged. If damage is of a concealed nature, you must contact the carrier immediately
or no later than three (3) days following delivery.
It is the responsibility of the consignee to file all claims for damage with the transportation company.
The system is shipped with a holding charge of dry nitrogen. Confirm unit is still pressurized as noted on tag.
Ensure specifications on electrical data plate matches incoming power supply.
NOTE: ACCESSORY ITEMS SUCH AS DRIER CORES, MOUNTING PADS, MODEMS, ETC. MAY BE PACKAGED
IN A SEPARATE CARTON. BE SURE THAT YOU RECEIVE ALL ITEMS.
Lifting
This refrigeration system is a heavy piece of machinery and careful considerations for lifting should be made before the
unit is lifted by any means. Each product has specific locations where they can be lifted. Failure to lift the unit properly
could cause damage to the unit or bodily harm to people in the area of the lift. Lifting cables and other equipment should
be prevented from contacting any of the unit piping or electrical components. Lifting/rigging should only be performed
by qualified personnel. See rigging information in coordination document for additional details.
Location of Equipment
All equipment must be located so it is level and easily serviced. Particular attention should be given to ensure compressors can be easily and safely changed, if needed. All systems must be located on a solid floor and must be leveled
within plus or minus ¼ inch. Use metal shims where required to support entire length of the system. Must be shimmed
under structural members only (typically every 2’ on racks or every 4’ on mechanical enclosures). Ensure unit positioning is in compliance with all pertinent spacing requirements/codes.
Location of Equipment Outdoor
•
•
•
The mounting platform or base should be level and located so as to permit free access of supply air to condenser.
Units must not be located in the vicinity of steam, hot air or fume exhausts.
The unit should be mounted away from noise sensitive spaces such as offices.
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Installation and Operation Manual
•
The unit must have adequate support to avoid vibration and noise transmission into the building. Sound and
structural consultants should be retained for recommendations.
Ground Mounting
The unit must be set on a flat and level foundation. A single piece concrete slab with footings extending below the frost
line and raised approximately six inches above ground level provides a suitable base. Raising the base above ground
level provides some protection from ground water, snow accumulation and wind-blown matter. The concrete slab should
be isolated from the building structure. Finally, before tightening mounting bolts, recheck the level of the unit.
Roof Mounting
Rooftop installations require adequate structural beams to support the weight of the unit and service personnel. The
design of the beams/supports must minimize deflection and attendant vibration transmission. Due to the weights
involved, a structural analysis by a qualified engineer may be required before mounting. Also, for sound sensitive
applications, unit vibration isolators should be used.
Ventilation Requirements
Kysor/Warren recommends ventilation in the range of 40-100cfm per compressor horsepower depending upon ambient
temperatures or as specified by customer. Cooler climates do not require as much ventilation as warmer climates. The
air intake should be positioned so that air passes over the units and should be sized for a maximum of 500ft/minute
velocity. Check national and local codes for ventilation requirements before installation.
Floor and Foundation Requirements
The total weight of a single unit will vary significantly dependent upon number of compressors and a variety of other
considerations. Allowances must be made for the parallel rack and all other equipment installed in the same area as
the parallel units. The location and installation of all equipment should be in accordance with all local and national code
requirements.
While each unit is constructed with a steel frame adequately designed to withstand vibration, the natural pulsating action
of the interconnected motor-compressors may cause considerable noise and vibration if the unit is not mounted on a
firm level surface and isolated from the structure of the building.
Vibration
Vibration isolation pads provided with the unit (or other proper consideration) must be utilized. These pads should
support the entire weight of the rack and should be placed between any shims and rack frame. Units should be
installed away from occupied spaces, corridors and auxiliary spaces to reduce the transmission of sound and vibration
to occupied spaces. The refrigerant piping should be flexible enough to prevent the transmission of noise and vibration
from the unit into the building. If the refrigerant lines are to be suspended from the structure of the building, isolation
hangers should be used to prevent the transmission of vibration. Where piping passes through a wall, it is advisable to
pack fiberglass and sealing compound around the lines to minimize vibration and retain flexibility in the lines. If the unit
is not mounted on a floor the equivalent of 6 inch thick properly reinforced concrete (and in other unique circumstances),
special vibration absorbing spring mounts (optional equipment) must be placed under the base frame of each unit. See
Figure 1 for view of Spring Isolator. The spring mounts are placed under the unit and the unit carefully lowered on to the
mounts. Note that no other mounting hardware is required and any unevenness in the floor or uneven weight distribution
may be compensated for by turning the spring mount leveling nuts with an open-end wrench. This adjustment should
be made after all piping is installed and the system is charged with refrigerant.
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Direct Expansion HFC Parallel Rack
Unit Vibration Isolation
Under certain critical conditions, it is recommended that vibration isolators, of a suitable type, be installed under the
base. The isolators must be designed for the operating weight of the unit. Rubber-in-shear or spring type isolators (by
others) are available for this purpose.
Figure 1. Vibration Pad and Spring Isolator
Leak Check (Rack)
To check the systems for leaks, leave all valves closed on suction, liquid and hot gas manifolds (the system is shipped
with a holding charge of dry nitrogen). Build the pressure to a maximum of 150 psig using dry nitrogen.
CAUTION: ALWAYS USE A NITROGEN PRESSURE REGULATOR WITH A NITROGEN TANK.
Allow to sit a minimum of 24hrs and confirm the system retains 150PSIG pressure.
Field Electrical
CAUTION: WIRING CONNECTIONS SHOULD BE MADE ONLY BY A LICENSED ELECTRICAL CONTRACTOR.
1.
2.
3.
4.
5.
6.
7.
8.
Check all connections and confirm they are secure.
Check all wires and ensure there are no frayed or exposed wires.
Make all field wiring connections per Kysor/Warren wiring diagrams and customer supplied specifications.
Electrical connections to the rack should include three-phase power and single-phase control circuits. These
are made in the control panel. The control panel is located in various places depending on the product family.
Parallel system units are available with compressors rated at 208/60/3, 460/60/3 and 575/60/3. For 208 VAC
systems a single power feed is required for the unit. For 460 and 575 VAC systems a separate 208/60/1 control
circuit supply is required; if electric defrost is used a 208/60/3 supply is normally required, which may be combined with the control circuit supply. An optional transformer may be added to step down the 460 (or 575) VAC
for the control circuit on each unit.
All field wiring must be in compliance with the national electrical code and local codes. Minimum unit wiring ampacity and maximum overcurrent protective device rating as calculated per the national electric code are shown
on the parallel system nameplate.
Typical 208 and 460 VAC wiring diagrams with typical circuit wiring for different types of circuits are included in
the wiring diagram section of this manual. All types of defrost circuits may be intermixed in the panel depending
on the individual store requirements. The wiring diagram sent with each parallel system is the diagram for that
particular unit and shows the circuit wiring as set up for that specific application.
Parallel systems units with optional heat reclaim normally require two wires from the store environmental control
panel supplying voltage requested by the customer.
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Installation and Operation Manual
Field Piping
CAUTION: REFRIGERANT PIPING CONNECTIONS SHOULD BE MADE ONLY BY A LICENSED CONTRACTOR.
1. Properly sized refrigeration lines are essential to good refrigeration performance. Suction lines are more critical
than liquid or discharge lines. Oversized suction lines may prevent proper oil return to the compressor. Undersized lines can rob refrigeration capacity and increase operating cost. Consult the technical manual or legend
sheet for proper line sizes.
2. Refrigeration lines in cases in line-ups can be reduced. However, the lines should be no smaller than the main
trunk lines in at least 1/3 of the cases and no smaller than one size above the case lines to the last case. Reductions should not exceed one line size per case. It is preferred to bring the main trunk lines in at the center
of the line-up. Liquid lines on systems on hot gas defrost must be increased one line size above the main trunk
line for the entire line up. Individual feed lines should be at the bottom of the liquid header.
3. Do not run refrigeration lines from one system through cases on another system.
4. Use dry nitrogen in lines during the brazing to prevent scaling and oxidation.
5. Suction and liquid lines should never be taped or soldered together. Adequate heat exchanger is provided in
the case.
6. Refrigeration lines should never be placed in the ground unless they are protected against moisture and electrolysis attack.
7. Always slope suction lines down toward the compressor, 1/2 inch each 10 feet. Do not leave dips in the line
that would trap oil.
8. Provide “P” traps at the bottom of suction line risers, 4 feet or longer. Use a double “P” trap for each 20-foot of
riser. “P” traps should be the same size as the horizontal line. Consult the technical manual or legend sheet for
proper size risers.
NOTE: A SUCTION LINE TRAP MUST BE INSTALLED AT THE POINT WHERE PIPING CHANGES THE
DIRECTION OF REFRIGERANT FLOW FROM ANY HORIZONTAL RUN TO AN UPWARD VERTICAL RUN.
Figure 4. Suction Line P Traps
Figure 5. Double Suction Riser Construction
9. Use long radius ells and avoid 45° ells.
10. Provide expansion loops in suction lines on systems on hot gas defrost (see expansion loops gas defrost in this
manual).
11. Strap and support tubing to prevent excessive line vibration and noise.
12. Brazing of copper-to-copper should be with an appropriate braze alloy (refer to customer specification). Dissimilar metals should be brazed with a minimum 45% silver solder.
13. Avoid the use of “bull head” tees in suction lines. An example is suction gas enters both ends of the tee and exits
the center. This can cause a substantial increase in pressure drop in the suction lines.
14. When connecting more than one suction line to a main trunk line, connect each branch line with an inverted
trap.
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Direct Expansion HFC Parallel Rack
15. Liquid lines should be sized for a minimum pressure drop to prevent “flashing”. Flashing in the liquid lines would
create additional pressure drop and poor expansion valve operation. If a system requires long liquid lines from
the receiver to the evaporator or if the liquid has to rise vertically upward any distance, the losses should be calculated to determine whether or not a heat exchanger is required. The use of a suction to liquid heat exchanger
may be used to subcool the liquid to prevent flashing. This method of subcooling will normally provide no more
than 20˚F subcooling on high pressure systems. The amount of subcooling will depend on the design and size
of the heat exchanger and on the operating suction and discharge pressures. An additional benefit from the use
of the suction to liquid type heat exchanger is that it can help raise the superheat in the suction line to prevent
liquid return to the compressor via the suction line.
16. Install all refrigerant components in accordance with applicable local and national codes and in accordance with
good practice for proper system operation.
17. Only suitable silver solder alloy should be used on suction and liquid lines.
18. Limit the soldering paste or flux to the minimum required in order to prevent contamination of the solder joint internally. Flux only the male portion of the connection—never the female portion. After brazing, remove the flux.
Typical Field Piping to Condenser
Figure 1 illustrates a typical piping arrangement involving a remote condenser located at a higher elevation, as commonly encountered when the condenser is on a roof and the compressor and receiver are on grade level or in a basement equipment room.
In this case, the design of the discharge line is very critical. If properly sized for full load condition, the gas velocity might
be too low at reduced loads to carry oil up through the discharge line and condenser coil. Reducing the discharge line
size would increase the gas velocity sufficiently at reduced load conditions; however, when operating at full load, the
line would be greatly undersized, and thereby create an excessive refrigerant pressure drop. This condition can be
overcome in one of the following two ways:
1. The discharge line may be properly sized for the desired pressure drop at full load conditions and an oil separator installed at the bottom of the trap in the discharge line from the compressor.
2. A double riser discharge line may be used as shown in Figure 2. Line “A” should be sized to carry the oil at minimum load conditions and the line “B” should be sized so that at the full load conditions both lines would have
sufficient flow velocity to carry the oil to the condenser. For more complete information, refer to the ASHRAE
Handbook on Systems.
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Installation and Operation Manual
Notes:
1. All oil traps are to be as short in radius as possible. Common practice is to fabricate the trap using three 90° ells.
2. Pressure relief valves are recommended at the condenser for protection of the coil.
3. A drain line check valve is recommended for applications where the condenser may be at a lower temperature
than the receiver.
Figure 1
Installation of all Filters and Driers
Install all filters and driers:
1.Suction
2.Oil
3.Liquid
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Figure 2
Direct Expansion HFC Parallel Rack
Refrigerant Line Insulation
NOTE: KYSOR/WARREN RECOMMENDATIONS SHOULD BE VIEWED AS MINIMUM REQUIREMENTS.
CUSTOMER SPECIFICATIONS MAY DIFFER.
Insulate suction lines from the cases to the compressor with a minimum of 3/4” wall thickness Armaflex insulation or
equal on low temperature cases to provide maximum of 65°F superheated gas back to the compressor (we recommend a return gas superheat lower than 65°F for optimum efficiency) and prevent condensation in exposed areas.
Insulate suction lines on medium temperature cases with 1/2” thick insulation in exposed areas to prevent condensate
dripping.
Long liquid lines run in areas exposed to high temperatures should be fully insulated with minimum 1/2” insulation.
Refrigerant Line Support
Strap and support tubing to prevent excessive line vibration and noise. All tubing clamps should have an insulating
material (i.e. Hydrasorb bushing) to prevent metal-to-metal contact.
Figure X Pipe Supports
•
•
•
•
•
Straight runs should be supported near each end.
Long runs require additional supports.
A general guide is:
• 3/8” to 7/8” every 5 feet
• 1 1/8” to 1 3/8” every 7 feet
• 1 5/8” to 2 1/8” every 10 feet
When changing directions, supports should be placed a maximum of 2 feet in each direction.
Piping attached to a vibrating object (such as a compressor or rack frame) must be supported in such a manner that will not restrict the free movement of the vibrating object. Rigid mounting in this situation can cause
fatigue failures.
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Installation and Operation Manual
Leak Test
To check the systems for leaks, leave all valves closed on suction, liquid and hot gas manifolds (the system is
shipped with a holding charge of dry nitrogen). Build the system pressure up 150-200 psig using dry nitrogen and
check for leaks. Each circuit can be leak checked in this way, one at a time.
After each circuit has been checked, open all valves to allow the pressure into the unit assembly. Check to be sure
that the pressure is throughout the assembly. Check all connections and accessories for leaks.
Particular attention should be given to:
• Braze joints
• Mechanical fittings (ensure all are tight)
• Valves (ensure all caps in place)
System Evacuation
A triple evacuation of the system is critical to ensure any residual non-condensables are removed from the system
prior to startup and to ensure reliable system operation. If mechanical receiver liquid level floats are used, they
should be installed before the first evacuation.
NOTE: TRANSDUCERS SHOULD NOT BE EXPOSED TO HIGH PRESSURE OR A LOW VACUUM (SHOULD BE
INSTALLED AFTER VACUUMS AND PRESSURE TESTS ARE COMPLETED).
Use only vacuum pumps specifically designed for system evacuation purposes, sized appropriately for the system.
All vacuum measurements should be taken using a high vacuum gauge capable of measuring pressure in microns.
To ensure a good/rapid system evacuation, use largest diameter vacuum hose or copper piping possible. Do not use
standard refrigerant charging hoses for vacuum procedure.
Do not use the refrigeration compressors to evacuate the system. Do not start the compressors while the system is in
a vacuum.
First Evacuation
After the system is leak checked, evacuate to 1500 microns for the first evacuation. Break vacuum with 2psi dry nitrogen.
Second Evacuation
The second evacuation should be pulled to a level of 1000 microns. Break system vacuum with 2psig dry nitrogen.
Add oil to compressors and separator/reservoir as needed. Install liquid drier cores.
Third Evacuation
The final evacuation should be pulled to a level of 500 microns. The final evacuation should hold for a minimum of 24
hours and the vacuum should only be broken by the introduction of refrigerant.
14
Direct Expansion HFC Parallel Rack
Start-Up Procedure
1. Add Oil (before third evacuation and during start-up as needed)
a. Follow the compressor manufacturer’s recommendation to charge each compressor with oil--typically ¼
to ½ sight glass.
b. Monitor oil level in reservoir closely and add oil as needed to maintain appropriate oil levels throughout
startup (typically ½ full).
WARNING: USE ONLY REFRIGERANT OILS SPECIFICALLY APPROVED BY COMPRESSOR MANUFACTURER
FOR THE SYSTEM DESIGN.
2. Verify pump rotation direction (if applicable)
3. Verify condenser fan rotation
4. Verify component functionality
a. Dry runs
b. Compressor bumps
c. Oil level confirmation
5. Verify EMS programming on controller
6. Confirm programming of VFDs on condensers (if equipped)
7. Confirm programming of EEPRs and EEVs
8. Charge with refrigerant
a. Isolate main liquid supply valve.
b. Introduce refrigerant through charging port as indicated on OEM literature.
c. Charge to 30-50% of receiver capacity with largest circuit energized
i. All other circuits should be isolated at this time.
ii. Only one compressor should be active. This should be the lowest capacity compressor in the system
iii. After reaching 50% of receiver capacity, bring on more compressors/circuits while monitoring pressures, temperatures and liquid levels.
WARNING: USE ONLY THE REFRIGERANT FOR WHICH THE EQUIPMENT IS SPECIFICALLY DESIGNED.
NOTE: CHARGE REFRIGERANT DIRECTLY FROM ORIGINAL VESSEL
9. Verify operational voltage and phase
a. Voltage for 208/230 not less than 195 volts or more than 253 volts.
b. All other voltages must not exceed +/- 10% of nameplate ratings.
c. Phase imbalance not to exceed 2%.
10. Verify circuit control and defrost (if supplied by OEM)
11. Record and verify operating amperages against nameplate and/or refrigeration legends
a. Defrost, Compressor, Condenser Fans, etc.
12. Verify control settings on all safety devices such as oil failure, high pressure, low pressure, etc.
13. Set all mechanical components per Customer or OEM recommendations (see site specific set points)
a. Drop Leg Pressure Regulators, Receiver Pressurization valves, LLPR, etc.
15
Installation and Operation Manual
Superheat
NOTE: PLEASE CONSULT COMPRESSOR MANUFACTURER FOR SPECIFIC SUPERHEAT RECOMMENDATIONS.
Superheat is the number of degrees a refrigerant is heated above its saturation temperature. The saturation temperature for a given refrigerant varies with pressure. A proper superheat is important because it ensures that no liquid will
reach the compressors.
It is important to note that there are multiple locations where superheat can be measured. These points are summarized in the table below.
Superheat Description
Location
Notes
Evaporator Superheat
Measured at the outlet of the evaporator/unit cooler/case.
Controlled by the thermal expansion
valve on the evaporator coil.
System Superheat
Measured in the suction line approximately 6 inches from the compressor
Superheat of gas entering compressor
Proper superheat at the compressor will enhance compressor life, performance and operating efficiency. If a system
operates with a superheat below compressor manufacturer’s recommendation, there is a risk of liquid returning to
the compressor. This could lead to improper oil circulation and damage to compressors. Excessive superheat may
cause poor efficiency and system operation as system capacity decreases with an increase in superheat. An excessive superheat setting may also shorten compressor life. In order to maintain optimal superheat, installers must follow
line sizing and insulation guidelines. Additionally, all fixtures should be set to the appropriate superheat.
Measuring superheat
1. Measure the suction pressure at the suction service valve of the compressor and determine the saturation
temperature corresponding to this pressure from a “Temperature-Pressure” chart.
2. Measure the suction temperature of the suction line about six inches to one foot back from the compressor
using an accurate thermometer.
3. Subtract the saturated temperature from the actual suction line temperature. The difference is superheat.
If adjustments to the suction superheat need to be made, the expansion valve at the evaporator should be adjusted.
16
Direct Expansion HFC Parallel Rack
Maintenance
Proper maintenance is critical to long term reliability and efficiency. The following recommendations should be followed as minimum standards:
Initial Startup
•
•
Change all filters and driers by end of first week of startup
If filters found to be dirty, repeat in 7 days
Weekly
•
•
•
•
•
•
•
•
Visually inspect equipment.
Check refrigerant charge.
Check compressor oil level and color.
Check compressor crankcase heater operation.
Check main power and control voltage.
Check appearance of area around the unit.
Check system pressures.
Check moisture indicator in liquid sight glass.
Monthly (do weekly checklist plus):
•
•
•
•
•
•
•
Check the system for leaks.
Check suction filters and liquid line filter driers for pressure drop.
Check all flanged connection bolts, fittings and line clamps for tightness.
Inspect condenser fan blades and motor mounts for cracks, loose set screws or mounting bolts.
Tighten all electrical connections.
Check operation and condition of contactors.
Check operation of auxiliary equipment.
Annually (do monthly checklist plus):
•
•
•
Obtain oil sample for analysis; change oil if required.
Change liquid line filter drier and suction filter cores.
Test all operating and safety controls and record in service log book
NOTE: THE ABOVE INFORMATION IS PROVIDED ONLY AS A GENERAL GUIDELINE TO AID SERVICING
PERSONNEL AND EQUIPMENT OWNERS IN MAINTAINING EQUIPMENT. DUE TO VARIABLES IN THE ACTUAL EQUIPMENT APPLICATION, OPERATING CONDITIONS, AND ENVIRONMENT RECOMMENDED SERVICE
INTERVALS MIGHT VARY.
Suction Filter
Replaceable core suction filters are supplied for all units. The flanged shell holds replaceable pleated filter elements
suitable for installation in the suction line of refrigeration systems. In this way any contaminants left in the system at
start-up can be removed before they circulate back to the compressor. The suction filters are shipped loose for field
installation.
Compressor Burnout Cleanup Procedure
One key benefit of a suction filter is its use in cleanup of a system after a burnout. Standard liquid cores can be installed in the shell to aid in the cleanup of acids and other contaminants from a motor burnout.
The following procedure can be used in case of a motor burnout.
17
Installation and Operation Manual
1. Determine the extent of the burnout. For mild burnouts where contamination has not spread through the system, it may be economical to save the refrigerant. Normally it is economical to save the refrigeration charge
if the system has service valves. A severe burnout exists if the oil is discolored, an acid odor is present and
contamination products are found in the high and low side. With this condition, extreme caution should be
exercised to avoid breathing the acid vapors and to prevent contaminated liquid from making contact with the
skin.
2. Thoroughly clean and replace all system controls, such as expansion valves, solenoids, check valves, reversing valves, oil separators, suction accumulators, etc. Remove all strainers and filter-driers.
3. Install a replacement compressor and make a complete electrical check.
4. Make sure the suction line adjacent to the compressor is clean. Install a liquid line filter-drier or a replaceable
cartridge designed for “cleanup” into the suction line shell.
5. Install a burnout core in the liquid line shell.
6. If the refrigerant is removed from the system, follow the evacuation procedure found on page 14 of this
manual.
7. Start the compressor and put the system in operation.
8. Record the pressure drop across the suction line filter and keep for reference.
9. Replace the suction line filter-drier blocks if the pressure drop becomes excessive.
10. Observe the system during the first 4 hours. Repeat step 8 as often as required, until no further change in
pressure drop is observed.
11. After the system has been in operation for 48 hours, check the condition of the oil for acids. If the oil test indicates an acid condition, replace the liquid and suction line filter- driers.
12. Check the system again after approximately 2 weeks of operation. If the oil is still discolored, or checks acid,
replace the liquid and suction line filter-driers.
13. Cleanup is complete when the oil is clean, odor free, and is determined to be acceptable by testing for acids
or other contaminants.
14. Replace the suction line filter-drier with suction line filters cores to minimize suction line pressure drop and to
provide maximum compressor protection.
Oil Control System
The oil control system provides a method of regulating the oil level in each individual crankcase. It does not require
that the compressors be the same make or model. The oil control system uses two or three basic components.
•
•
•
Oil Separator
Oil Reservoir (low pressure systems only)
Oil Level Regulator
Oil Separator
The purpose of an oil separator is to separate oil from refrigerant in the systems discharge line so it can be stored in
the oil reservoir to be used in the compressors.
Oil Reservoir
The purpose of the oil reservoir is to provide storage for oil to allow the system to compensate for various operational
conditions. The oil reservoir can separate or integrate (on a high pressure system) into the oil separator.
Oil Filter
A filter is used to remove debris from circulation in order to prevent it from becoming an obstruction in the system.
The filter can be a sealed or a removable/replaceable cartridge type.
18
Direct Expansion HFC Parallel Rack
Oil Level Regulators
Each compressor has an oil level regulator attached to control the oil level in each individual compressor. The regulators are supplied oil by the common oil reservoir, which in turn is supplied by the oil separator.
The oil level regulator controls the oil level in each individual crankcase with a float-operated valve. It holds back
excess oil until the oil level in the compressor crankcase drops, lowering the float and opening the valve. Oil from the
oil reservoir will then be admitted into the crankcase, raising the float. When the correct level is reached, the valve will
close stopping the flow of oil to that particular crankcase.
As standard, all oil level regulators are adjustable. The regulator is UL listed at 450 psig working pressure and a 2250
psig burst strength. All oil regulators are suitable up to a maximum differential pressure of 90 psig. Sporlan models are
standard.
Oil Pressure Reducing Valve (OPRV)
This valve ensures appropriate oil feed pressure to the oil level regulators. These valves accomplish this by reducing
the diameter of the high pressure oil lines and maintaining a set pressure.
IMPORTANT: AN OIL CONTROL SYSTEM DOES NOT REPLACE THE NEED FOR PROPER SYSTEM DESIGN.
AN OIL CONTROL SYSTEM WILL DRASTICALLY REDUCE THE AMOUNT OF OIL GOING THROUGH THE
SYSTEM. CORRECT PIPING, SUCTION TRAPS, AND PROPER SIZING OF VALVES, CONTROLS, AND COMPONENTS MUST STILL BE IMPLEMENTED TO INSURE THE SYSTEM WILL WORK PROPERLY.
19
Installation and Operation Manual
PROBLEM
POSSIBLE CAUSES
POSSIBLE CORRECTIVE STEPS
Compressor will not run
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
1. Close switch.
2. Check electrical circuits and motor winding for shorts or grounds.
Investigate for possible overloading.
Replace fuse after fault is corrected.
3. Overloads are automatically reset.
Check line.
4. Repair or replace.
5. Determine type and cause of shutdown and correct it before resetting
safety switch.
6. None. Wait until calls for cooling.
7. Repair or replace coil.
8. Check motor for open windings,
short circuit or burn out.
9. Check all wire junctions. Tighten all
terminal screws.
10. Refer to page 17.
Compressor noisy or vibrating
1. Flooding of refrigerant into crankcase.
2. Improper piping support on suction
or liquid line.
3. Worn compressor.
4. Scroll compressor rotation reversed.
5. Oil levels too high.
1.
2.
3.
4.
5.
Check setting of expansion valves.
Relocate, add or remove hangers.
Replace.
Rewire for phase change.
Reset oil float and/or drain excess oil
from system.
High discharge pressure
1. Non-condensables in system.
2. System overcharges with refrigerant.
3. Discharge shutoff valve partially
closed.
4. Fan not running.
5. Head pressure control setting.
6. Dirty condenser coil.
1.
2.
3.
4.
5.
6.
Remove the non-condensables.
Remove excess.
Open valve.
Check electrical circuit.
Adjust.
Clean.
Low discharge pressure
1. Faulty condenser temperature regulation.
2. Suction shutoff valve partially closed.
3. Insufficient refrigerant in system.
4. Low suction pressure.
5. Variable head pressure valve.
1. Check condenser control operation.
2. Open valve.
3. Check for leaks. Repair and add
charge.
4. See corrective steps for low suction
pressure.
5. Check valve setting.
High suction pressure
1. Excessive load.
2. Expansion valve overfeeding.
1. Reduce load or add additional equipment.
2. Check remote bulb. Regulate superheat.
Low suction pressure
1.
2.
3.
4.
1. Check for leaks. Repair and add
charge.
2. Clean.
3. Replace cartridge(s).
4. Clean strainers.
5. Check and reset for proper superheat.
6. Check means for regulating condensing temperature.
7. Check for proper sizing.
20
Main switch open.
Fuse blown.
Thermal overloads tripped.
Defective contactor or coil.
System shut down by safety devices.
No cooling required.
Liquid line solenoid will not open.
Motor electrical trouble.
Loose wiring.
Phase loss monitor inoperative.
Lack of refrigerant.
Evaporator dirty or iced.
Clogged liquid line filter drier.
Clogged suction line or compressor
suction gas strainers.
5. Expansion valve malfunctioning.
6. Condensing temperature too low.
7. Improper TXV.
Direct Expansion HFC Parallel Rack
Little or no oil pressure solenoid valve
operation.
1. Clogged suction oil strainer.
2. Excessive liquid in crankcase.
3. Low oil pressure safety switch defective.
4. Worn oil pump.
5. Oil pump reversing gear stuck in
wrong position.
6. Worn bearings.
7. Low oil level.
8. Loose fitting on oil lines.
9. Pump housing gasket leaks.
1. Clean.
2. Check crankcase heater. Reset
expansion line
3. Replace.
4. Reverse direction of compressor
rotation.
5. Replace compressor.
6. Add oil and/or through defrost.
7. Check and tighten system.
8. Replace gasket.
Compressor loses oil
1.
2.
3.
4.
Lack of refrigerant.
1. Check for leaks and repair. Add
Excessive compression ring blow by.
refrigerant.
Refrigerant flood back.
2. Replace compressor.
Improper piping or traps.
3. Maintain proper superheat at compressor.
4. Correct piping.
Compressor thermal protector switch
open.
1.
2.
3.
4.
5.
Operating beyond design conditions.
Discharge valve partially shut.
Blown valve plate gasket.
Dirty condenser coil.
Overcharged system.
1. Add components to bring conditions
within acceptable limits (i.e., CPR/
EPR valves, addtional condenser
surface, liquid injection, etc.).
2. Open valve.
3. Replace gasket.
4. Clean coil.
5. Reduce charge.
21
Installation and Operation Manual
Refrigerant Pressure Temperature Chart
22
Direct Expansion HFC Parallel Rack
Monthly Refrigerant Receiver Level Chart
A data sheet template that allows monthly refrigerant receiver level to be tracked.
Year: _____________________
Store location: _________________________
Rack ID: _______________________
Jan
Feb
March
April
May
June
July
Aug
Sept
Oct
Nov
Dec
Sept
Oct
Nov
Dec
100%
95%
Refrigerant Receiver Level
90%
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
A data sheet template that allows monthly refrigerant receiver level to be tracked.
Year: _____________________
Store location: _________________________
Rack ID: _______________________
Jan
Feb
March
April
May
June
July
Aug
100%
95%
Refrigerant Receiver Level
90%
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
23
Installation and Operation Manual
Rack Start-up Report
Completed by: ________________________________________
Date: _________________________________
Project manager: _______________________________________________________________________________
Install contractor: _______________________________________________________________________________
Install company: ________________________________________________________________________________
_____________________________________________________________________________________________
Customer: ___________________________________________
Store: _________________________
Address: _______________________________________________________________________________
City, State: ___________________
Zip code: ____________________
Date shipped: __________________
_____________________________________________________________________________________________
Rack serial number: _____________________________________________________________________________
Model number: _________________________________________________________________________________
Refrigerant: ____________________________________________________________________________________
_____________________________________________________________________________________________
24
Direct Expansion HFC Parallel Rack
Oil Controller Test
Oil
Mechanical Test
Oil Pressure
HP
Cut-off Controller
Test
Cut-off Mechanical
Test
HP Cut-off
Set Point
Time Delay
Set Point
Demand Cooling
Controller Test
Demand Cooling
Mechanical Test
Amps
L3
Amps
L2
Amps
L1
Unloader Test
Comp #
Compressors
1
2
3
4
5
6
7
8
9
10
Rack Controls
Designed Set Point Actual Set Point
Mechanical Test
Group 1 Low Pressure Control
Group 2 Low Pressure Control
Master High Pressure Control
Receiver Pop-off
Phase Loss Monitor
Drop Leg Hold Back Valve
Heat Reclaim - Electric
Heat Reclaim - Refrig
Liquid Pressure Regulator
Liquid Press Bypass Solenoid
Receiver Level Indicator
Receiver Level Alarm
Receiver Bypass (surge)
Receiver Pressure Regulator
Oil Pressure Regulator
Subcooler EPR
Subcooler Stage 1
Subcooler Stage 2
Electronic Controller:
Liquid set point:
Superheat set point:
Refrigerant:
Valve size:
25
Installation and Operation Manual
Misc Controls
Control
Test
Notes
Leak Detection System
Case Lighting Contactor
VFD information:
Serial numbers: _______________________________________________________________________________
Model Number: _______________________________________________________________________________
Controlling sensor drop leg:
Independent ambient sensor:
All set points are to Walmart spec:
Speed ramps up and down properly:
NO/YES
NO/YES
NO/YES
NO/YES
Circuits
ESR & LLS Verified
Defrost Amps L1
Defrost Amps L2
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
Serial numbers: _______________________________________________________________________________
Model Number: ________________________________________________________________________________
Amps per fan: _________________________________________________________________________________
Number of fans: _______________________________________________________________________________
26
Direct Expansion HFC Parallel Rack
Fans rotating proper direction: No/Yes
Fans on inactive side shut off: No/Yes
Condenser pump out de-energized: No/Yes
Condenser pump out energized: No/Yes
Hold back valve energized: No/Yes
50% solenoid valve energized: No/Yes
VFD information:
Serial number: ________________________________________________________________________________
Model number: ________________________________________________________________________________
27
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