Dimplex A8M User manual

A-Class Heat Pumps
A8M, A12M & A16M Installation Manual
dimplex.co.uk
8/60472/0
Issue 1.07

Contents
1. Introduction 5
1.1 Manual Information 5
1.2 Important Safety Information 6
1.3 Intended Use 8
1.4 Legal 8
1.5 Heat Pump Labels and Pipe Connections 9
1.6 Heat Pump Dimensions 9
1.7 Scope of Delivery 10
1.7.1 Installation pack 1 - Space heating and Dimplex A-Class cylinder 11
1.7.2 Installation pack 2 - Space heating and Dimplex standard cylinder 12
1.7.3 Installation pack 3 - Space heating only 13
2. Important pre-installation information 14
2.1 Connection to the Grid - Notifying the DNO 14
2.1.1 Heat Pump Sizing 14
2.2 Heat Pump Location 14
3. Installation instructions 16
3.1 16
3.1.1 Temperature Control Devices 18
3.1.2 Space Heating Zones 19
3.1.3 Location of Wiring Centre 19
4. Installation 20
4.1 Important - Plumbing Information 20
4.1.1 Pipe Sizing Information 22
4.1.2 Buffer tank 23
4.1.3 Adjusting the spring loaded by-pass valve (if fitted) 23
4.1.4 Metering for the Domestic Renewable Heat Incentive - UK 24
4.2 Electrical Information 25
4.2.5 Access to Electrical Connections - Opening the heat pump 25
4.2.6 Electrical Connections - power and Modbus cable heat pump connections 26
4.2.7 Modbus Cable Information 28
4.2.8 Opening and Installing the User Interface 28
4.3 Heat Pump Controller / Commissioning 30
4.3.1 Important pre-startup information 30
4.4 Commissioning 31
4.4.1 Starting the heat pump in cold weather 31
4.4.2 General / Schematic 31
4.4.3 Waterside Check 33

4.4.4 Temperature Check 34
4.4.5 Electrical connections 34
4.4.6 Water Flow Check 34
4.4.7 DHW set-up 36
4.4.8 Electrical connections (DHW) 36
4.4.9 DHW Test 36
4.4.10 Disinfection (thermal) 38
4.4.11 Weather compensation 39
4.4.12 Heating curves 39
4.4.13 Comfort level 40
4.4.14 Setup complete 40
4.5 Additional Installer Menu Options 40
4.5.1 Service menu 40
4.5.2 Message log 40
4.5.3 Output Tests 41
4.5.4 Defrost 41
4.5.5 Operating data 41
4.5.6 History 41
5. System Health Check / Maintenance 42
5.1 Heat pump: 42
5.2 Electrical: 42
5.3 Hydraulics: 42
5.4 Indoor settings: 42
6. Appendices 43
6.1 44
6.2 Refrigeration cycle 45
6.3 Schematics - Example 1 46
6.4 Schematics - Example 2 47
6.5 Schematics 1, 2, 3 & 4 : Space Heating Only 48
6.6 Schematics 5, 6, 7, 8 : Zone space heating + DHW 49
6.7 Schematics 9, 10, 11, 12 : Bivalent space heating 50
6.8 Schematics 13, 14, 15, 16 - Bivalent zone space heating + DHW 51
6.9 52
6.10 53
6.11 54
6.12 Controller cable connections 55
6.13 56
6.14 Installer hand-over form 57
6.15 58

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1. Introduction
1.1 Manual Information
NOTE: This manual is intended for electricians and qualied installers only!
This manual is intended for installers and electricians installing Dimplex A-Class air-source heat pumps.
All installers must have prior knowledge regarding the installation of Dimplex A-Class air-source heat pump
systems, and must be competent to install the system safely and successfully.
Installers must have knowledge of any local or national standards, codes or regulations that may apply, as
well as safe methods of practice. Dimplex accept no responsibility for compliance with these codes and
regulations on the part of the installer.
All electrical installations must be carried out in accordance with local and national standards and
regulations, including BS 7671.
NOTE: Repair should not be attempted by unqualied persons.
NOTE: Retain this manual for information
The instructions included in this manual are important for the correct installation and use of Dimplex
A-Class air-source heat pumps. Please ensure that you retain this manual for reference.
The specications and information supplied in this manual may be subject to change without notice at the
discretion of Dimplex. All attempts have been made to ensure that this document is complete and that the
information supplied is correct at the time of publication, however Dimplex will assume no responsibility
for damages (including consequential and indirect / accidental damages) resulting from reliance on the
information presented in this document.
NOTE: Check that you have the latest issue of this manual before installation.
NOTE: Go to http://www.dimplex.co.uk/customer_support/downloads and enter your A-Class heat
pump model number for the latest PDF download of this manual.
These original instructions must be left with the user after installation, including the hand-over form at the
back, where the installer should record key information during commissioning.
Unauthorised reproduction of this document is prohibited.

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1.2 Important Safety Information
• Do not tilt the heat pump by more than 45° in any
direction.
• Do not lift without using correct lifting devices.
• Ensure that all clearance dimensions are observed - this
is important for correct heat pump operation and air ow.
• Use a suitable lifting device in accordance with any
relevant health and safety regulations.
• Do not move or transport the heat pump at.
WARNING: When using lifting rods to lift the heat pump,
straps must also be used to prevent toppling.
Figure 1:Maximum tilt angle
NOTE: Leaving a clear pathway for delivery will allow the heat pump to be delivered as close to the
installation site as possible to minimize moving / lifting.
• Never use cleaning agents containing sand, soda, acid or chloride as these can damage surfaces
/ components.
• Do not use muddy or dirty water to ll the heating system. This can cause components to
malfunction and poses a corrosion risk to the system.
• If the heat pump may be disconnected from the power supply for long periods of time, or where
power supplies are susceptible to failure, antifreeze must be added to the system.
Example: Mono ethylene glycol at 25% volume to protect down to -14°C in a holiday home.
• Use a suitable ltration protection system and a corrosive additive to prevent the formation of
oxides or solids in the heat pump condenser.
• This appliance can be used by children aged from 8 years and above and persons with reduced
physical, sensory or mental capabilities or lack of experience and knowledge if they have been
given supervision or instruction concerning use of the appliance in a safe way and understand
the hazards involved.
• Children shall not play with the appliance.
• Cleaning and user maintenance shall not be made by children without supervision.
NOTE: The heat pump contains refrigerant at high pressure.
Safety measures are in place to avoid system pressure build up;
Stage 1: Pressure transducer stops compressor.
Stage 2: Pressure switch switches heat pump off. All safety devices reset automatically.

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WARNING: Before removing the cover of the heat pump, cylinder or wiring centre, ensure that all
electrical circuits are isolated.
NOTE: The heat pump has a multi-layered, software generated alarm management system, which
prevents it from running outside its operating limits.
NOTE: If an alarm / message occurs, the heat pump will attempt to take remedial action before causing
the system to stop completely if the problem persists. However, the overriding safety feature is the high
pressure switch, which de-energises the main contactor supplying power, in accordance with EN378.
NOTE: This device is suitable for mains connection only (230V, 1P&N, 50Hz) and is not suitable for
operation with an electrical generator or power modulator, due to possible effects on the quality of the
electrical supply. Any attempt to do so will void warranty.
• Means for disconnection from the supply mains must be incorporated into the xed wiring in
accordance with the national wiring regulations.
• This device must be installed in accordance with national wiring regulations.
• The local wiring regulations should always be followed paying particular attention to the mixing of
low voltage and extra low voltage cabling.
• Ensure the incoming power supply and the distribution board are suitably rated.
• Ensure that the regulations specied by the local electricity supplier have been adhered to.
• All fuse rating and protective overload device information is provided in the wiring label located
on the inside of the front bottom panel of the heat pump. For instruction on how to remove this
panel please see section 3.1.
• The installation of a heat pump designated residual current device (type B RCD) having a rated
residual operating current not exceeding 30mA is recommended, in accordance with local
regulations (BS7671 for UK installations).
• The correct earthing (grounding) of the heat pump is of the utmost importance.
CAUTION: The heat pump has a high leakage current and must be properly grounded for safety in
accordance with local and national regulations regarding equipment with a leakage current exceeding
3.5ma.
CAUTION: Two separate, designated RCD devices should be tted - one for the heat pump and one for
the cylinder. The heat pump system must not share an already existing domestic RCD device.

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1.3 Intended Use
This product is designed to extract heat from outside air to provide energy for a water-based heating
system, and is intended for domestic and light commercial use. Any other use beyond that intended by
the manufacturer is prohibited. This requires the user to abide by the manufacturer’s product information.
Please refrain from tampering with or altering the device.
NOTE: Additional heating may be required if the heat pump is intended to dry out a new or renovated
building, as the initial heat load may be higher than the design load.
1.4 Legal
The construction and design of the heat pump complies with all relevant EU directives (see CE declaration
of conformity in Appendices section).
When connecting the heat pump to the power supply, the relevant EN and IEC standards must be adhered
to. Any further connection requirements stipulated by the network operation must also be observed.
When connecting to the heating system all applicable regulations must also be adhered to.
NOTE: Products not installed with the Dimplex hydraulics packs will not be supported by Dimplex. This
includes but is not limited to thermal stores.
NOTE: Installation and any service work on the heat pump may only be performed by an authorised and
qualied installer and after-sales service technicians.

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1.5 Heat Pump Labels and Pipe Connections
Figure 2:Heat pump connections and labels
1.6 Heat Pump Dimensions
Figure 3:Heat pump dimensions
1
3
2
4
1
2
Water outlet connection
Water inlet connection
Water connection label
3
Rating label
4
Model:
Serial No. 001
8.0
R410A 2.0 kg bar C20 A
C°h/³m0073riA
aPk1.4C°h/³m1.2
Protection: IP 24 kg
12.30 kW COP 4.72
12.90 kW COP 2.20
1/75733/0
The refrigeration cycle is hermetically sealed.
Contains Kyoto-Protocol defined fluorinated greenhouse gases.
All work to be carried out on this unit is to be carried out by a
competent person.
Power Factor
A-2W55 P
Heating
Air to Water Variable Speed Heat Pump
Max Op.
Pressure
Revision:
Single Phase 230V/50Hz
45
kW
Δp
Electrical Power (Max)
P
Heating
A7W35
Heating Water:
EN14511-2 Conditions
A16T
Fabrication Date:
0.99
Fuse Protection
Min.
Flow
T
y
pical
Flow
-20 / +35
+25/+65
Min / Max
Op. Temp.
Min / Max
Op. Temp.
Weight 130
GDC Group
Greenbank Industrial Estate,
Rampart Road,
Newry
Northern Ireland
BT34 2QU
Tilt angle
Do not clamp
on sides MCS HP0017
HEAT PUMPS

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1.7 Scope of Delivery
Please ensure you check the scope of delivery before signing any delivery documentation.
Below is a guideline checklist for what should be contained in each pack.
Claims for missing or damaged parts after signing for the delivery will not be accepted.
There are 3 options to select from when installing a Dimplex Heat Pump:
Pack 1 - Space heating and Dimplex A-Class Cylinder
This pack should contain four boxes;
• Heat Pump
• ACCHYPK Hydraulics Kit A (contains all of the necessary hydraulic components)
• Cylinder
• Cylinder Accessories
A separate wiring centre is not required as the wiring centre is built into the cylinder.
Pack 2 - Space heating and Dimplex Standard Heat Pump Cylinder
This pack should contain ve boxes;
• Heat Pump
• ACCHYPK Hydraulics Kit A (contains all of the necessary hydraulic components)
• Cylinder
• Cylinder Accessories
• Wiring Centre
A separate wiring centre is required as the wiring centre is not built into the standard cylinder.
Pack 3 – Space heating only
This pack should contain three boxes;
• Heat Pump
• ACSHYPK Hydraulics Kit B (contains all of the necessary hydraulic components)
• Wiring Centre
• Accessories
A separate wiring centre is required to wire the circulation pumps and controls.
NOTE: Details for each installation pack are shown on pages 11-13.
All hydraulic kits listed in the following tables include the following documents;
• ASHP Installation manual, part number 8/60472/0 A8M, A12M, A16M
• ASHP User manual, part number 8/60476/0 A8M, A12M, A16M
Please ensure that these manuals are left with the end user. Manuals must be stored safely for
future reference.

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1.7.1 Installation pack 1 - Space heating and Dimplex A-Class cylinder
No. Description Part No.
1 A-Class heat pump A8M / A12M / A16M
10 Blanking plugs (x4, stored inside heat pump) 4592624105
Hydraulics Kit A ACCHYPK
2 User interface (UI) 1754600
3 ERES spring loaded by-pass valve (22mm comp. tting) 1755780
4 3-port diverting valve (28mm comp. ttings) 1755750
5 Pump - UPM GEO 25-85 180 (1500mm cable) 1755740
6 Isolation valves (1” swivel BSP to 28mm comp.) - Flow 1755760
7 Isolation valves (1” swivel BSP to 28mm comp.) - Return with strainer 1755770
13 2 x Circulation Pump Gate Valve 11/2” swivel to 28mm comp
2 x Washer 30.1x21x2mm 1756090
Dimplex A-Class cylinder kit, which includes;
8 A-Class cylinder with integrated buffer
9Safety group DHW side; expansion vessel, hose and bracket, inlet group,
tundish
11 Drain
12 3x copper pipes - Pump to buffer / cylinder
14 Air vent
Pipe connections to coil, pipe, drain and vent.
Pipe connections to pump.
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1.7.2 Installation pack 2 - Space heating and Dimplex standard cylinder
NOTE: Cylinder required for pack 2 installation; please see Dimplex EC-EAU cylinder manual for range of
non A-Class cylinders.
No. Description Part No.
1 A-Class heat pump A8M / A12M / A16M
10 Blanking plugs (x4, stored inside heat pump) 4592624105
Hydraulics Kit A ACCHYPK
2 User interface (UI) 1754600
3 ERES spring loaded by-pass valve (22mm comp. tting) 1755780
4 3-port diverting valve (28mm comp. ttings) 1755750
5 Pump - UPM GEO 25-85 180 (1500mm cable) 1755740
6 Isolation valves (1” swivel BSP to 28mm comp.) - Flow 1755760
7 Isolation valves (1” swivel BSP to 28mm comp.) - Return with strainer 1755770
12 2 x Circulation Pump Gate Valve 11/2” swivel to 28mm comp
2 x Washer 30.1x21x2mm 1756090
8 Dimplex standard cylinder
Wiring centre module, which includes;
9 Wiring centre module 049162
11 1 x Temperature probe (NTC10) for DHW
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1.7.3 Installation pack 3 - Space heating only
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No. Description Part No.
1 A-Class heat pump A8M / A12M / A16M
10 Blanking plugs (x4, stored inside heat pump) 4592624105
Hydraulics Kit B ACCHYPK
2 User interface (UI) 1754600
5 Pump - UPM GEO 25-85 180 (1500mm cable) 1755740
6 Isolation valves (1” swivel BSP to 28mm comp.) - Flow 1755760
7 Isolation valves (1” swivel BSP to 28mm comp.) - Return with strainer 1755770
42 x Circulation Pump Gate Valve 11/2” swivel to 28mm comp
2 x Washer 30.1x21x2mm 1756090
Wiring centre module, which includes;
9 Wiring centre module 049162
11 1 x Temperature probe (NTC10) for DHW
Accessories
8 100L / 200L / 300L buffer tank (depending on installation) 025586
3 2kW buffer immersion element 363610
e

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2. Important pre-installation information
CAUTION: You must read and understand all of the information in this section before attempting an
installation!
2.1 Connection to the Grid - Notifying the DNO
Before you connect a heat pump to the grid, the necessary permissions must be granted by the
distribution network operator. Not obtaining the necessary permissions may result in an unexpected
network upgrade charge, and may compromise the integrity of the local supply if a ‘disturbing load’ is
connected to the network.
The required forms are supplied by Dimplex and must be lled in by the heat pump installer alongside the
client. We recommend notifying the DNO as early as possible in the planning stage to discuss the project
and any additional information. Further information can be found on the Energy Networks website
(www.energynetworks.org) or from your local DNO.
2.1.1 Heat Pump Sizing
NOTE: Ensure that the correct size heat pump has been selected in accordance with the latest version of
MIS3005 (for UK installations).
If a non A-Class heat pump cylinder is being used, ensure that it has been accurately sized with the
appropriate coil surface area of the cylinder to match the heat pump’s output and ow rate requirements,
and that all necessary hydraulic connections have been considered in connecting it to the heat pump
system.
Ensure that suitable heat emitters have been sized in accordance with the BRE publication Design of low-
temperature domestic heating systems: A guide for system designers and installers. To maximise
system efciency it is important to design the system with the lowest ow temperature possible.
For more information on sizing heat emitters or to order BRE publications, please visit the BRE bookshop
website: www.brebookshop.com
2.2 Heat Pump Location
• The heat pump must be installed outdoors.
• The fan should not face prevailing winds to ensure correct air ow through the evaporator.
• The minimum clearance distances provided in this manual must be followed.
• NO obstructions in front of the heat pump fan for at least 1m.
• Clearance is important for good air ow and service access to the heat pump.
• Do not position the heat pump close to bedroom windows, as the fan and compressor may be
operational at night.

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Figure 4:Poor air ow
CAUTION: Ensure that there are no obstructions in front of the heat pump fan for at least 1m - however,
2m is recommended. ANY type of obstruction in front of the heat pump, even small shrubs, can block the
air ow and cause cold air recirculation.
Figure 5:Good air ow with recommended clearances

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3. Installation instructions
3.1 Positioning and xing the heat pump
• The heat pump must be xed onto a level, stable concrete plinth of minimum dimensions approx.
1000mm x 500mm.
• The concrete plinth must be able to withstand the unit’s weight of 110-140kg (depending on
model).
• A minimum distance of 50mm between the heat pump and the edge of the plinth is required on
all sides.
CAUTION: The minimum clearance distances around the heat pump are shown in gure 3; 300mm
at the rear for air ow, 500mm each side for service and at least 1000mm in front of the fan to avoid air
recirculation.
Figure 6:Required service and air ow clearance dimensions

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1) Check that plinth dimensions are within the required clearances, as per figure 6.
Positioning the heat pump in a conned space, frost hollow or well will result in reduced heat pump
efciency.
The cold air which is expelled by the fan cannot disperse and may be drawn back into the system.
This means that the heat pump may be operating using a lower inlet temperature than what is actually
available from the ambient air.
Figure 7:Removing the panels to t xing bolts and condensate pipe
CAUTION: Ensure that the condensate pipe is uncoiled and is running to a drain
2) Remove the heat pump panels to mark drilling holes on plinth.
The heat pump panels must be removed so that the base panel is visible. To do this, remove the screws
and slide the panels downwards and out.
Once the panels are removed, mark the holes for the xing bolts (gure 6), then lift or slide the heat pump
out of the way to drill the holes. Leave the panels off until all xing and positioning of the heat pump, bolts
and condensate pipe have been carried out (steps 3 -4).
3) Run the condensate pipe to an appropriate drain
The condensate drain pipe is coiled up inside the heat pump for protection during transportation. In order
to access this for installation, the panels will need to be removed (see gure 7). The condensate pipe must
be uncoiled and run through the condensate pipe hole in the base panel to the drain.

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• The pipe should be prevented from exposure to the elements, as this may contribute to freezing
issues. The condensate pipe must run through the base panel and underground to the drain. Freezing
of this pipe due to incorrect installation can result in irreparable damage and void warranty.
• Approximately 2 litres of condensate water are drained from the system every time a defrost cycle
occurs (approximately once every hour in cold and humid weather). Therefore, it is essential that the
condensate pipe is fed into a rain water drain or soak away to allow for safe disposal of the excess
water, away from footpaths or patios.
• The removal of condensate must be secured and the condensate pipe must be kept free from debris
and frost.
• The condensate pipe should not run into sewer pipe as fumes may travel into the heat pump and
cause corrosion to the evaporator coil.
4) Inserting the fixing bolts
Once the holes for the xing bolts are drilled, place the heat pump back onto the plinth and x in place
using the M10 bolts supplied in the installation pack.
5) Positioning and Fixing Indoor Components
The controller and thermostats should be installed on internal walls in living area to reect the correct
room temperature, and away from direct sunlight, drafts (windows and doors) and heat emitters.
3.1.1 Temperature Control Devices
• The controller/user interface that is supplied with the Dimplex A-Class heat pump is used as a
heat pump controller as well as a space heating and domestic hot water (DHW) controller.
The preferred option is to use the user interface as a room temperature control device.
• The user interface and room thermostats should be installed indoors in a location that is out of
reach of children, but where the LCD display can be easily seen (usually 1.2m – 1.7m from the
oor).
While only one user interface is currently available per system, there are additional options
of either temperature probes or mechanical thermostats, which can be used to control the
temperature in up to four zones.
• Mechanical thermostats provide less control over the heating system, while the temperature
probe option allows the heat pump to sense changes in demand and adjust accordingly. The
temperature probe option is generally recommended over the mechanical thermostat option.

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3.1.2 Space Heating Zones
A zone is dened as the physical area of the home in which temperatures are controlled by each individual
device. For example, there might be a user interface installed in the living area, in which case this may be
referred to as zone 1. There may also be a temperature probe installed upstairs in the sleeping/bedroom
area, which would then be designated as zone 2, and so on.
Extra zones are an additional, optional feature of the heating system. The standard package comes with
one user interface and the possibility of four separate zones. Each heating zone can be assigned a heat
curve specic to the type of heat emitters.
3.1.3 Location of Wiring Centre
If a Dimplex A-Class cylinder is used, the wiring centre is built in to the A-class cylinder and pre-wired.
If a non A-Class cylinder is used, the wiring centre module must be installed.
The wiring centre module is designed to be wall mounted, and it is recommended that it is installed in
close proximity to the cylinder to allow for installation of components which require a control cable
(modbus) connection, i.e. pump, DHW probe, 3-port valve and heat pump connections.

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4. Installation
4.1 Important - Plumbing Information
NOTE: To simplify underoor heating initial screed heating, it is essential to have a thermostatic mixing
valve on the underood heating (UFH) manifold.
This allows the heat pump to run at higher temperature and capacity when the screed is cold.
• If multiple heat emitter circuits are installed, operating at different ow and return temperatures (such
as under oor heating and standard radiators), a mixing valve must be used on low temperature
circuits to prevent high temperature water from entering the under oor heating manifold.
• Isolation valves (non-return valve and ball valve with strainer), supplied in the Dimplex heat pump
hydraulics pack, allow the strainer to be removed and cleaned without having to drain the system.
• Existing hot water systems should be ushed prior to connection to the heat pump to remove all
contaminants and impurities, in accordance with the latest version of MIS3005.
• Flow and return isolation valves and piping must be tted to each of the heat pump water connections
on the back of the heat pump, as shown in gure 1.
• The isolation valve on the return is also tted with a non-return valve and a strainer (included in the
Dimplex heat pump hydraulics pack). This means that in order to clean the strainer, the system does
not have to be drained. Instead, it is possible just to close the isolation valves on the return and
remove the strainer. This way, the only water that will be lost from the system is that between the non-
return valve and strainer.
• The strainer must be tted in order to prevent contamination of the condenser heat exchanger. If an
alternative strainer is used, it must be at least 7 microns in size.
• System should be pressurised and the system pressure must be checked once valves are re-opened.
• Direct condensate drain pipe to soak away or drain.
• All piping must be properly insulated and external length kept to a minimum.
• The return isolation valve provided in the hydraulics pack has a built in strainer to help prevent debris
entering the condenser and must be tted.
• The system must be lled and ushed with clean fresh water to ensure the removal of all the air from
the installation.
CAUTION: When lling the system, always ensure that clean, fresh water is used. Using dirty or
untreated water may cause severe damage to components and may affect the efciency of the system
when operating.
• Air bleed points must be installed at the highest point in the system; in particular, the installer must
remember to install an air bleed on the heat pump pipe if it is a local high point since there is no air
bleed point on the heat pump itself. Dimplex recommend the use of a power ush and purge cart to
facilitate this process.