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Compact Heat Pump
Commissioning Manual
Copyright ©2012 Kensa Engineering Ltd
Compact Heat Pump Commissioning Manual Version 4
Page 1 of 35
Contents
Section
Description
Page
1....................... Introduction .................................................................................. 3
2....................... Safety Information ........................................................................ 4
2.1........................... Access ...................................................................................................................... 4
2.2........................... Lighting .................................................................................................................... 4
2.3........................... Tools and Consumables ........................................................................................... 4
2.4........................... Handling ................................................................................................................... 4
2.5........................... Residual Hazards ...................................................................................................... 4
2.6........................... Freezing ................................................................................................................... 4
2.7........................... Disposal/Decommissioning ..................................................................................... 4
3....................... General Product Information ........................................................ 5
4....................... Client and Heat Pump Data ........................................................... 6
5....................... Heating System Data ..................................................................... 8
6....................... Ground Arrays ............................................................................... 10
7....................... Switching the Heat Pump On ......................................................... 12
8....................... Checking for Air in the Water Pump .............................................. 14
9....................... Changing the Antifreeze Alarm Point ............................................ 16
10..................... Changing the Return Water Set Point ............................................ 17
11..................... Taking the ‘B’ Readings ................................................................. 18
12..................... Weather Compensation ................................................................ 20
13..................... Commissioning Sign Off ................................................................. 21
14..................... Faults That Can Occur During Commissioning ................................ 22
14.1......................... Carel Controller Seems Dead ................................................................................... 22
14.2......................... Carel Display is Operational But Remote Display is Dead ........................................ 23
14.3......................... LP Alarm Displayed and Red Light Flashes ............................................................... 25
14.4......................... A1 Alarm Displayed and Red Light Flashes .............................................................. 26
14.5......................... E1,E2 and E3 Alarms ................................................................................................ 28
14.6......................... E4 Alarm .................................................................................................................. 29
14.7......................... HP Alarm (High Pressure Gas) ................................................................................. 31
14.8......................... Tp Alarm—Low Pressure Underfloor or Groundside ............................................... 33
14.9......................... Compressor Sounds Noisy ....................................................................................... 34
15..................... Fault Finding Summary .................................................................. 35
Compact Heat Pump Commissioning Manual Version 4
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1. Introduction—A message from the Managing Director
Kensa Engineering has been manufacturing ground source heat pumps since
1999. In the early days, it was difficult to find contractors willing to consider the
technology. As a consequence, Kensa made considerable efforts to simplify the
installation process. With the advent of the Microgeneration Certification
Scheme the number of certified installers is increasing and the company is now
reaping its rewards as heat pumps become mainstream heating appliances.
The purpose of this manual is to guide you as an MCS installer, through the commissioning process. It is
expected that all the required information has been provided to allow you to connect the heat pump
correctly and that the commissioning will be a simple process.
Please note if you experience any problems please feel free will to speak to the Technical Support Team
on 01872 862140. Opening hours are 8.00am to 5.00pm .
Finally, please contact Kensa should you have any questions, wish to consider ground source heat pumps
for any future projects or even just to share your experiences of using a ground source heat pump with us.
Simon Lomax
Managing director
Kensa Engineering Ltd
Compact Heat Pump Commissioning Manual Version 4
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2. Safety information
Safe operation of this unit can only be guaranteed if it is properly installed and commissioned in
compliance with the manufacturer’s requirements. General installation and safety instructions for pipeline
and plant construction, as well as the proper use of tools and safety equipment must also be complied
with.
Manufacturer:Kensa Engineering
Mount Wellington
Chacewater
Truro
Cornwall
TR4 8RJ
Tel 01872 862140
www.kensaengineering.com
The product is designed and constructed to withstand the forces encountered during normal use. Use of
the product for any other purpose, or failure to install the product in accordance with these Installation
and Commissioning Instructions, could damage the product, will invalidate the warranty, and may cause
injury or fatality to personnel.
2.1 Access
Ensure safe access before attempting to work on the product. Arrange suitable lifting gear if required.
2.2 Lighting
Ensure adequate lighting, particularly where detailed or intricate work is required.
2.3 Tools and Consumables
Before starting work ensure that you have suitable tools and / or consumables available.
2.4 Handling
Manual handling of large and /or heavy products may present a risk of injury. Lifting, pushing, pulling,
carrying or supporting a load by bodily force can cause injury particularly to the back. You are advised to
assess the risks taking into account the task, the individual, the load and the working environment and use
the appropriate handling method depending on the circumstances of the work being done.
2.5 Residual Hazards
Many products are not self-draining. Take due care when dismantling or removing the product from an
installation.
2.6 Freezing
Provision must be made to protect products which are not self-draining against frost damage in
environments where they may be exposed to temperatures below freezing point.
2.7 Disposal/Decommissioning
Kensa offer a life time decommissioning service for this product. This is available on a return to base basis
(carriage at users’ cost).
Disposal of any antifreeze water mix should follow the disposal instructions as laid out on the COSH Safety
Data Sheet in the Installation and Commissioning Manual.
Compact Heat Pump Commissioning Manual Version 4
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3. General Product Information
This manual gives guidance on how to commission a Kensa ground source heat pump. The manual is
designed for use by MCS approved installers who undertake commissioning of a Kensa Heat pump as part
of the service and grant process for their clients.
The Kensa Compact Single Compressor Heat Pump is designed to provide a low cost renewable heat
source for a buildings heating system. In addition, and if required, the Kensa Compact can also provide
domestic hot water. Heat pumps can provide lower running costs and will generate significantly lower
carbon emissions compared with traditional fossil fuels.
The Kensa Compact Single Compressor Heat Pump is designed for straightforward installation and the
installation must conform to all relevant construction and electrical codes and comply with the
requirements of the Microgeneration Certification Scheme (MCS) MIS3005 ’Requirements for Contractors
undertaking the Supply, Design, Installation, Set to Work Commissioning and Handover of Microgeneration
Heat Pump Systems’.
The following sections detail the steps to be taken for the final commissioning of the unit. It advises the
steps and possible errors that could occur during commissioning. The idea of the manual is to work
through each section in turn while referring to the fault section as and when required. Many faults found
with heat pumps generally occur due to wiring faults or in setting the unit up. Therefore it is recommend
that initially a detailed check is carried out should there be a problem.
The manual can be used as a record of the commissioning or simply as a guide through the commissioning
process.
Information taken during the commissioning can help with any future fault finding and also provide
information to satisfy the requirements for the commissioning certificate from the Low Carbon Buildings
Programme.
Compact Heat Pump Commissioning Manual Version 4
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4. Client and Unit Data
Commissioning Engineer
Date
Client Name
Address
Postcode
Telephone Number
Site Telephone Number
Installation Address
(If different)
Installation Postcode
Type of Property (Flat, Bungalow,
House)
Style of Property (mid-terraced, endterraced, semi, detached)
Number of Bedrooms
Compact Heat Pump Commissioning Manual Version 4
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Product
Note : Check for initial wiring faults on three phase systems
Serial Number
Heating or Cooling
Note : For Cooling Applications please contact Kensa Technical
Department
kW rating
kWh per annum
Note : This figure can be obtained from the clients SAP report
Fuel displaced
Ensure all MCB’s are turned off
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5. Heating System Data
Type of Heating System
Note: If Radiators then the return flow temperature might need to be set
higher. See Changing the Return Water Set Point - Section 10
Make of underfloor
Type of underfloor system
Ground floor
First floor
Second floor
Note: This will affect the final running temperature of the heat pump.
Screed will be 35oC, suspended floors will need to set at 40 to 45oC. See
Changing the Return Water Set Point - Section 10.
Number of underfloor heating
manifolds
Does each manifold have its own
pump?
Note: This only applies for systems 4kW +
Have all the mixing valves been
removed?
Are 25% of the zones left open or is a
buffer vessel fitted?
Note: When switching a heat pump on for the fist time and the weather
is very cold (below 3 deg C), the best way is to open one underfloor zone
at a time. This puts less demand on the ground arrays. This is called a
flat battery syndrome.
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Control Philosophy
Note: How is the underfloor controlled i.e. Underfloor control unit,
thermostat, time clock, linked terminals
Is the heat pump able to receive a call
for heat
Note: This is required to ensure that power can be supplied to the unit
during the commissioning. This can be done via the control unit or in its
simplest form linking terminals 1 and 2 on the wiring block.
Link between terminals one and two
Compact Heat Pump Commissioning Manual Version 4
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6. Ground Arrays
Type of Ground Arrays
Number
Length
Horizontal or vertical trench
Trench separation distance
Note : For slinkies this should be 5m, for straight pipe 1m
Has the array been purged in both
directions with a Clarke SPE1200SS
purge pump
Note: If No, the ground arrays need to be purged using the Clarke Purge
Pump SPE1200SS available from Machine Mart. Air might be in the system if purged incorrectly.
Antifreeze (quantity added)
Antifreeze concentration (checked
with two random samples)
Sample 1
Sample 2
Note: If the consistency of antifreeze to water is not 20% or protected to
-10oC the heat pump will more than likely go out on an A1 alarm which
means that ice can form in the heat exchanger. The system MUST have
the right amount of antifreeze protection. If low additional antifreeze
must be added and the system repurged. Following this commissioning
can continue. Concentration should be checked via a refractometer.
Pipe visually inspected
backfilling (kinks and nicks)
before
Pipe leak tested to BS805 Section
11.3.3.4
Pressure
A
B
C
Note : The ground array pressure will drop over the first year due to the
pipe relaxing within the ground, hence the fill loop needs to be
connected if the pressure needs increasing at a later date. Any short
term drop generally indicates a leak.
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Pressure gauge readings on heat
pump.
Load
Gauges are below the water pumps
within the heat pump.
Ground
Note : The pressure should be between 2 and 6 barg. The pressure
switch activates at 0.3 barg and resets at 1.8. If the pressure to low top
up using the ground fill loop or underfloor fill loop to at least 2 barg. If
pressure to high release pressure using schrader valves.
Load side gauge
Ground side gauge
Have the flow arrows been added to
the manifolds?
Note : Flow direction arrows need to be placed on the manifold to
indicate flow and return for future reference. This is a requirement of
MCS.
Have the water pumps impellors been
spun?
Note: See directions within the installation manual. This is to ensure
pumps are free to spin. The 30/10 pump (16kW and above) does not
have a bleed screw
Has the antifreeze been circulated
thoroughly through the arrays and
heat pump?
Note: The antifreeze must be mixed thoroughly otherwise any unmixed
solution will ice and freeze within the heat exchanger resulting in an A1
alarm. If not done this can be achieved by running the ground water
pump (DO NOT SWITCH THE 25AMP MCB ON ONLY THE 4AMP). On twin
compressors both the 4amps need to be turned on. It can take about
45min to completely mix.
4amp mcb, should be marked on the
mcb. Usually for single phase 2nd mcb
in (check on twin), three phase 4th mcb
in (check on twin)
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7. Switching the Heat Pump On
Visual check of heat pump installation
Note : Check to make sure no leaks, no obvious damage to the unit.
Unit level?
Front cover removed
Note: Ensure power to the unit is isolated
Visual inspection of wiring
Note: If any visual damage halt the commissioning and call an electrician.
Type of Consumer unit MCB fitted
Amps
Rating
Note: Type D's are preferred, however type 'C' is acceptable for single
phase heat pumps with smart starts.
Power turned on to the unit
Note: Power turned on via the main MCB in the consumer unit
Turn only the 4amp MCBs on.
Note: On a twin both 4amp MCBs need to be turned on. DO NOT TURN
ANY 25AMP MCBs ON
4amp mcb, should be marked on
the mcb. Usually for single phase
2nd mcb in (check on twin), three
phase 4th mcb in (check on twin)
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Reading on display
Carel controller dead (see section 14.1)
Carel is working but remote display is not (see section 14.2)
LP alarm flashes with red light (see section 14.3)
A1 alarm flashes with red light (see section 14.4)
E1, E2 or E3 flashes with red light (see section 14.5)
E4 alarm flashes with red light (see section 14.6)
Any software errors?
Heat pump comes to life and the
return flow temperature is displayed
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8. Checking for Air in the Water Pumps
If not already on, switch only the 4
amp mcbs on (two on a twin). Do not
switch any 25 amp mcbs on.
4amp mcb, should be
marked on the mcb.
Usually for single phase
2nd mcb in (check on
twin), three phase 4th mcb
in (check on twin)
The underfloor pump should switch
on and the underfloor pressure gauge
should register approx 1/2 bar drop in
pressure
Note: If no movement see section below
Repeat three times
Load side gauge
Ground side
gauge
Around 5 seconds later the contactor
should operate (large clunk) and the
ground pressure should increase
about 1/2 bar
Note: If no movement see section below
Repeat three times
No movement in gauges.
If the ground or load side pressure
gauges do not show a change in
pressure this generally means that air
is around the pump. Turn the 4 amp
MCBs off and bleed the pipe at the
top of the pipe into the heat
exchanger via the Schrader valve.
Note : If no fluid is around the impeller the pump generally gets very hot
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Load side bleed point
Ground side
bleed point
Check pump is not stuck and spin
pump
Note: See directions within manual. This is to ensure pumps are free to
spin. The 30/10 pump (16kW and above) does not have a bleed screw
Check all valves on manifolds open
Check flow direction arrows on
manifold pumps correct.
Note : Pumps will be pumping against each another if flow direction is
the same.
Check power supply to pumps
Note : Pumps might be faulty if power supply ok. Check if running. If
pump faulty then contact Kensa Technical Department
Was the system purged correctly?
Note : If not repurge
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9. Changing the Antifreeze Alarm Point
The antifreeze alarm is factory set at 0oC. This needs to be reset during commissioning to -5oC. Failure to
do this (or lack of antifreeze) could cause the heat pump to display an A1 alarm and turn itself off during
cold weather. The antifreeze alarm point should only be changed once the correct antifreeze quantities
have been added and confirmed.
1
For the upper external controller, press and hold
SET until 0 is displayed. For the lower controller
within the heat pump, press and hold SEL and PRG
together.
2
Press and hold the UP button, and release when
66 is displayed
3
Press SEL
4
Display will now read S-P (which means "Set
Parameter")
5
Press SEL, and -/- is displayed
6
Press SEL
7
Press the UP arrow until -/04- is displayed
8
Press SEL
9
Press the DOWN arrow to change from 3 to 0
10
Press SEL
11
Press PRG
12
Press the UP arrow until -d- is displayed
13
Press SEL
14
Press the UP arrow until d03 is displayed
15
Press SEL and the Antifreeze Setpoint is displayed
16
Press and hold the DOWN arrow to change from
0.0 to -5.0
17
Press SEL
18
Press PRG
19
Press the DOWN arrow until -/- is displayed
20
Press SEL
21
Press the UP arrow until -/04- is displayed
22
Press SEL
23
Press the UP arrow to change from 00 to 03
24
Press SEL
25
Press PRG twice until S-P is displayed
26
Press and hold PRG until the display returns to
normal
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External Controller
Internal Controller
Note: Heat pumps are shipped with the antifreeze
alarm set at 0C, this needs to be reset to -5oC at
commissioning. This needs to be done for both sides
if it is a twin compressor model.
10. Changing the Return Water Set Point
Return water set point is factory set at 30oC to provide water into the underfloor at 35oC. For underfloor
in joisted systems this will possible need to be increased to 40-45oC depending on floor coverings.
Radiators require a higher flow temperature and hence the temperature should be set at 45oC. A mix of
underfloor and radiators will also require 45oC.
1
For the upper external controller, press and hold SET until 0 is displayed. For the lower
controller within the heat pump, press and hold SEL and PRG together.
2
Using the up arrow go to 11
3
Press SEL
4
Display will now read S-P (which means "Set Parameter")
5
Press and hold SEL until -/- is displayed
6
Press the DOWN arrow until -r- is displayed
7
Press SEL and r01 is displayed
8
Press the UP arrow until r03 is displayed
9
Press SEL
10
The return water temperature setpoint is displayed
11
Press the UP or DOWN arrows to change the setpoint
12
Press SEL
13
Press PRG twice until S-P is displayed
14
Press and hold PRG until the display returns to normal
For twin compressor units both controllers i.e. both internal or both external controllers will
need to be set with new return flow temperatures. The right hand controller generally has a
return set temperature one degree higher than the left hand controller.
Return set points
Single compressor
Twin compressor
Left compressor
Compact Heat Pump Commissioning Manual Version 4
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Right compressor
11. Taking the B Readings
The ‘B’ readings are measurements of the temperatures and pressures within the heat pump. They give
an indication of how well the heat pump is working and will help with any diagnostics.
Turn the 25amp MCB for the
compressor on
25amp mcb, should be
marked on the mcb and
for single phase the first
mcb. On three phase all
three mcb's should be
turned on.
Compressor noisy?
Note: If yes, see section 14.9
Run compressor for 5-10 mins and
then record any errors.
A1 alarm see section 14.4
LP alarm see section 14.3
Tp alarm see section 14.8
E1 to E3 alarm see section 14.5
E4 alarm see section 14.6
Reading the ‘B’ temperatures and
pressures
Note : For twins readings have to be taken and recorded from both
controllers
1
Press and hold SEL until -/- is
displayed
2
Press the UP arrow until -b- is
displayed
3
Press SEL and b01 is displayed
4
Press SEL
5
The temperature of water b01 single
returning from the underfloor is
displayed
twin
Note: Return flow temperature should read between 0 and 30oC. If
above 30oC check that the return flow temp hasn’t been changed. If
the flow temperature is set correctly and reading above 30oC then
check sensors are connected and call the Kensa Technical
Department
When taking the b01 reading you can check for no flow by watching
how fast the heat is dissipated when the compressor is not running.
This will confirm that flow is present.
Compact Heat Pump Commissioning Manual Version 4
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6
Press SEL
7
Press the UP arrow once until b02
is displayed
8
Press SEL
9
The temperature of water return- b02 single
ing from ground arrays is displayed
twin
Note: Return ground temperature should read between 15 and
-5oC. If the b02 temperature is around room temperature, the
probe could have come lose. Trace the wiring back to yellow probe
on heat exchanger to confirm ok. If problem persists contact Kensa
Technical Department.
10
Press SEL
11
Press the UP arrow once until b03
is displayed
12
Press SEL
13
The temperature of water going b03 single
out to the ground arrays is
displayed
twin
Note: b03 is the temperature leaving the ground side of the heat
pump. If b03 is below the antifreeze set point and it has not gone to
alarm, A1, then check the antifreeze alarm set point. This should be
set to -5oC. See Section 9.
14
Press SEL
15
Press the UP arrow once until b04
is displayed
16
Press SEL
17
The refrigerant pressure in Barg is
displayed
b04 single
twin
Note: Take b04 when compressor running. b04 is the gas pressure
and this should be between 4.6 and 2.2. If weather compensator is
fitted then you will not be able to read the gas pressures. If b04 is
reading below 2 then the heat pump might be low of gas.
Note: When the ground is very cold the heat pump can go out on LP
alarm and b04 is very low. This can happen when a heat pump is
switched on for the first time and the building is cold. The building
needs to be heated up one zone at a time (flat battery)
Note: If b04 is to high, the expansion valve may need adjusting.
Contact Kensa Technical Department.
Note: Check sensor wiring as could be a bad connection. Call the
Kensa Technical Department if problem still present
18
Press PRG twice until S-P is
displayed
19
Press and hold PRG until the display
returns to normal
Check the b readings are logical, ie, that the load return temperature is below the outlet temperature and that the
ground outlet is below the inlet. If not this could indicate that the sensors are incorrectly positioned.
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12. Weather Compensation
It is advised that weather compensation is not enabled for underfloor systems operating on off-peak
tariffs and is only used on radiators. Even then Kensa recommend the system is left without weather
compensation for at least 12 months. The heat pump must be fully commissioned before weather
compensation is enabled and the b04 probe is removed.
To read b04 the weather compensator from the bottom of the carel needs to be unplugged and the carel
pressure probe plugged back in. The -/04– parameter needs to be reset to 1 following the same procedure
as outlined below. Once the b04 reading is taken the weather compensator can be plugged back in and
-/04- enabled as below.
New panel mounted Carel
Old Din rail mounted Carel
Carel pressure probe connection
1
Unplug the pressure transducer from the rear of the Carel (or for older grey units bottom right
hand side of Carel)
2
Plug the weather compensation sensor into the rear of the Carel (or for older grey units bottom right hand side of Carel)
3
Press and hold SET, and release when 0 is displayed
4
Press and hold the UP button, and release when 66 is displayed
5
Press SEL
6
Display will now read S-P (which means "Set Parameter")
7
Press SEL, and -/- is displayed
8
Press SEL
9
Press the UP arrow until -/04- is displayed
10 Press SEL
11 Press the DOWN arrow to change from 1 to 3
12 Press SEL
13 Press PRG twice until S-P is displayed
14 Press and hold PRG until the display returns to normal
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13. Commissioning Sign Off
The unit should now be commissioned and operating correctly.
The user manuals should be left with the client and the data collected within this commissioning process
can be used to complete any grant forms.
Comments
Commissioning Engineer
Signature
Print
Date
Company
MCS Accreditation Number
Telephone
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14. Faults that can occur during Commissioning
14.1 Carel controller Seems Dead
Check that power to the Heat pump is
on
Check that there is a live enable signal
over terminals one and two
Note: If a live enable signal can not be obtained from the heating control
signal, disconnect and link terminals 1 and 2
Link between terminals one and two
Check Carel fuse inside electric box
Note: If the fuse has blown a spare fuse is taped to the HP sensor
Carel fuse
Check wiring is correct
Faulty Carel
Note: Contact Kensa Technical Department
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14.2 Carel Display is Operational but Remote Display is Dead
Check that the remote cable is
connected correctly
For older din-rail mounted units check
that the RS485 'chip' is present and in
position on the Carel main unit
RS485 chip
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Check the wiring to the Carel,
transformer and remote display
power supply
Note: Push and hold the plug in the back of the remote display. If
the display then works, the connection on the remote display is
damaged
.
Grey
Brown
Remote Display Connection from the Carel
Blue
Old Din Rail
mounted Carel
Back of the remote display
New panel
mounted Carel
Remote display maybe faulty
Note: Contact Kensa Technical Department
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14.3 LP Alarm Displayed and Red Light Flashes
Check that LP switch wiring (on refrigerant) is
correct
LP pressure switch
Pressure transducer
(b04)
Check b04 reading
1
Press and hold SEL until -/- is displayed
2
Press the UP arrow until -b- is displayed
3
Press SEL and b01 is displayed
4
Press the UP arrow once until b04 is displayed
5
Press SEL
6
The refrigerant pressure in Bar is displayed
b04 single
twin
Note: If b04 can't be read the weather compensation
might be fitted. See Section 12
Note: If b04 is below 2 barg contact Kensa Technical
Department
7
Press PRG twice until S-P is displayed
8
Press and hold PRG until the display returns to
normal
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14.4 A1 Alarm Displayed and Red Light Flashes
An A1 alarm generally indicates no flow or that the compressor has run with air in the ground arrays and
that the heat exchanger has frozen. Also check the pump impeller is not stuck.
Note : If no fluid is around the impeller the pump generally gets very
hot. See Section 8
Check the b readings from the unit
1
Press and hold SEL until -/- is
displayed
2
Press the UP arrow until -b- is
displayed
3
Press SEL and b01 is displayed
4
Press SEL
5
The temperature of water returning b01 single
from the underfloor is displayed
6
Press SEL
7
Press the UP arrow once until b02 is
displayed
8
Press SEL
9
The temperature of water returning b02 single
from ground arrays is displayed
twin
twin
Note: b02 is the ground return temperature
10
Press SEL
11
Press the UP arrow once until b03 is
displayed
12
Press SEL
13
The temperature of water going out b03 single
to the ground arrays is displayed
twin
Note: b03 is the ground flow temperature, if this is below -5oC then
the unit will not operate and needs to be switched of until b03 is
above 0oC. If b03 is above -5oC and below 0 the A1 alarm needs to
be set to -5oC to allow commissioning.
14
Press SEL
15
Press the UP arrow once until b04 is
displayed
16
Press SEL
17
The refrigerant pressure in Barg is
displayed
18
Press PRG twice
displayed
19
Press and hold PRG until the display
returns to normal
until S-P
b04 single
is
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twin
Check to ensure flow around ground
arrays
Note: Check the pump. See Section 8
Double check antifreeze quantities
and concentration.
Note: Check the antifreeze quantities and concentration using a
refractometer. Reconfirm purging. All antifreeze supplied must be added
to the system.
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14.5 E1,E2 and E3 Alarms
E alarms generally mean a loss of contact with a sensor used to measure b0 temperatures.
Note: any damage contact Kensa Technical Department
Check that the temperature probes
leading to the Carel are fitted properly
and not loose.
Note: The sensors mounted within the heat exchanger are not
accessible. Loose connections cannot be easily rectified and if any
damage contact Kensa Technical Department.
Note: E1 fault can also indicate a problem with the DHW relay
Old Din Rail mounted Carel Controller
Sensor connector
New panel mounted Carel
Controller
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14.6 E4 Alarm
E4 alarms are generally a result of a faulty weather compensation sensor or incorrect commissioning.
Check for a damaged external
weather compensation sensor
Note : If damaged contact Kensa Engineering to organise a replacement.
Has the heat pump been
commissioned
with
weather
compensation
Note: See section 12
Check for damaged external temperature probe wires
Note : Check connections. If not easily rectified contact Kensa Technical
Department
Sensor
Green Terminal
connection
block.
Main Terminal Block
Check refrigerant pressure transducer
is ok
Note : If not easily rectified contact Kensa Technical Department
Pressure transducer
(b04)
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Check the temperature probe wiring
is correct
Note : Check connections. If not easily rectified contact Kensa Technical
Department
Temperature
probe connections
Carel pressure probe
connection
Old Din Rail mounted
Carel controller
New panel mounted Carel controller
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14.7 HP alarm. (High Pressure Gas)
HP alarms indicate the heat pump is over heating and is generally an indication of no or low flow around
heating distribution circuit because of air in water pump, or stuck water pump impellor, or heating
distribution system valves/actuators closed.
No flow on underfloor system. Check Flow?
all manifolds are open and underfloor
manifold pumps are not fighting each
another.
Note: 90% of the time Hp fault is due to no flow on the distribution side.
Note: When taking the b01 reading you can check for no flow by
watching how fast the heat is dissipated when the compressor is not
running. This will confirm that flow is present.
Note: b04 reading needs to be taken when the compressor is running.
All valves open?
Air in underfloor system?
Pumps fighting each another?
Check 3 way diverter valves
Underfloor pump running?
Note: Circulation pump might be stuck. Spin pump etc.
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Check wiring to HP switch
HP Pressure Switch
If HP alarm still showing then possible
faults might be
1) HP switch might be faulty
2) To much gas
3) Blocked gas system.
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Note : Contact Kensa Technical Department
14.8 tp Alarm - Low Pressure Underfloor or Ground Side
‘tp’ alarms occur due to low pressure in either the ground or the load side. This could be due to an
insufficient initial pressure, pipe relaxation or leaks.
Low pressure on underfloor or ground
arrays, try topping the pressure up.
Note: Ground arrays are topped up by using the fill loop on the heat
pump. The load side (heating) system should have it’s own individual
top up . On the load side there should be an expansion vessel to keep
the pressure stable due to the temperature changes from the Heat
pump.
Note: The low pressure switch operates (for both sides) at 0.3 barg, but
the pressure needs to be increased to above 1.8 barg to reset.
Heat pump ground array fill
Check connectors back to LP ground
and load switch
Low ground water pressure
switch
Low load water
pressure switch
If pressure continues to drop, this
indicates a possible leak in the system.
Pressure test the problem side.
If tP alarm still present possible causes are:
1) LP switch and pressure gauges
might be faulty
Note : Contact Kensa Technical Department
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14.9 Compressor sounds noisy
Contactor chattering on or off
Contactor might need changing, check contacts. Contact Kensa Technical
Department.
Compressor makes a loud shrieking
noise
hp switch is faulty or access valve not depressing. Contact Kensa
Technical Department
Compressor sounds like its trying to
run backwards
Mainly 3 phase - incorrect wiring on the phases. Check wiring and rewire.
If rewiring doesn't solve the problem then call Kensa Technical
Department
Check compressor is not rubbing on
casing
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15. Fault Finding Summary
Many faults which occur on commissioning are found to be due to incorrect wiring or setting up, therefore
it is recommended that a thorough check is carried out should there be a problem.
Symptom
Blank display on software controller
Possible Cause
Action
No power supply
Check wall mounted electrical isolator switch
or call electrician
Controls MCB tripped
Call electrician to investigate cause
There is no call from the time-clock or
thermostat for heat pump operation
Programme time-clock according to manufacturer’s instructions
Compressor not running but display
reading temperature near setpoint
Heat pump is up to temperature
No fault
Display flashes fault code tP
Low water pressure in the ground or heating
system side due to pipe relaxation or other
pressure loss.
Check the pressure gauges below the two
water pumps. The pressures should be between 1 and 2 bar. If below this, the pressure
needs to be increased above 1.8 bar
To increase the pressure in either circuit, the
cold fill valve will need to be opened. The
Ground cold fill is provided with every Kensa
heat pump, and is found on the right hand
side of the heat pump, underneath.
The heating distribution system should have
it’s own fill point.
Display flashes fault code HP
Overheat warning. No or low flow around
heating distribution circuit because of air in
water pump, or stuck water pump impellor,
or heating distribution system valves/
actuators closed.
Bleed the heating distribution system pump
within the heat pump, using the schrader
valve above the pump.
Check that the water pumps are operational
and spin the impellors (see the Installation
Manual)
Display flashes fault code LP
Display flashes fault code A1
HP can also be temporarily displayed when
the heat pump reverts from DHW to space
heating mode.
Low gas pressure in machine. Can occur
simultaneously with an A1 alarm.
Can occur temporarily on first start up when
unit is new or after a long period out of use.
Freeze protection system activated. Low or
no water flow on the ground (cold) side of
the machine. Can also occur after many
months of running in very cold weather.
No action
Check that the water pumps are operational
and spin the impellors (see the Installation
Manual)
If symptom persists outside of the two listed
circumstances, contact Kensa Technical department.
No action
Check antifreeze has been added and unit
commissioned correctly.
Check that the water pumps are operational
and spin the impellors (see the Installation
Manual)
Ensure no flow restrictions and wait approximately 4 hours (with the machine turned off)
for automatic reset.
Display flashes fault code E1, E2, E3 or E4
Loss of contact with probes inside heat
pump. E4 could be loss of contact with
weather compensation sensor
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Refer to Kensa Technical Department