Grant HPIDSYSLLHKIT User manual

UK | DOC 0184 | Rev 0.3 | PROVISIONAL | February 2022
Grant
Combined Volumiser/Low Loss Header
Installation Instructions

GRANT ENGINEERING (UK) LIMITED
Hopton House, Hopton Industrial Estate, Devizes, Wiltshire, SN10 2EU
Tel: [phone] Fax: [phone]
Email: [email protected] www.grantuk.com
This manual is accurate at the date of printing but will be superseded and should be disregarded if specications and/or appearances are changed in the interests of continued product improve-
ment. However, no responsibility of any kind for any injury, death, loss, damage or delay however caused resulting from the use of this manual can be accepted by Grant Engineering (UK)
Limited, the author or others involved in its publication.
All good sold are subject to our o󰀩cial Conditions of Sale, a copy of which may be obtained on application.
© Grant Engineering (UK) Limited. No part of this manual may be reproduced by any means without prior written consent.
IMPORTANT NOTE FOR USERS
These installation instructions are intended to guide the installer
in the installation of the Grant Combined Volumiser/Low Loss
Header.
SPECIAL TEXT FORMATS
The following special text formats are used in these instructions
for the purposes listed below:
! WARNING !
Warning of possible human injury as a consequence of not
following the instructions in the warning.
! CAUTION !
Caution concerning likely damage to equipment or tools
as a consequence of not following the instructions in the
caution.
! NOTE !
Used for emphasis or information not directly concerned
with the surrounding text but of importance to the reader.
Page 2
PRODUCT CODES COVERED
These instructions cover the following product codes:
Product code Product Description
HPIDSYSLLHKIT Grant Combined Volumiser / Low Loss Header
SERVICING
The Low Loss Header/Volumiser should be inspected at least
every twelve months, when the heat source and/or heating
system is serviced.

1 INTRODUCTION 4
1.1 General 4
1.2 Construction 4
1.3 Product contents 4
2 TECHNICAL DATA 5
2.1 Technical specication 5
2.2 Dimensions 5
3 INSTALLATION 6
3.1 General 6
3.2 Regulations and Standards 6
3.3 Location 6
3.4 Clearances 6
3.5 Unpacking 6
3.6 Installation procedure 6
3.7 Heat pump ow and return
connections 6
3.8 System connections 8
3.9 Volumiser only connections 8
4 ELECTRICAL 10
4.1 General 10
4.2 Electrical connections 10
4.3 Immersion heater 11
4.4 Electrical connections between lead
and supplementary heat pumps 12
5 OPERATION 13
5.1 General 13
5.2 Aerona³ heat pump parameter
settings 13
5.3 Parameter settings for supplementary
immersion heater operation 13
5.4 Parameter settings for assisting
defrost process 14
5.5 Parameter settings for supplementary
heat pump operation 14
! NOTE !
These Installation Instructions must be read in conjunction
with the Aerona³ Installation and Servicing Instructions
supplied with the heat pump.
Contents Page 3
CONTENTS

Section 1: IntroductionPage 4
1.1 GENERAL
The Grant Combined volumiser/low loss header provides the
functions of both a volumiser and low loss header in one unit,
with an integral 3kW electric immersion heater, for use with Grant
Aerona³ air source heat pumps.
As a volumiser it provides an extra 11.5 litres to the system
volume connected to the heat pump.
As a low loss header it gives hydraulic separation of the primary
circuit of the heat pump from the secondary system circuit. This
allows the ow rate through the heat pump to be maintained
irrespective of the di󰀨erent temperatures and ow rate in the
secondary system circuit.
The factory-tted 3kW electric immersion element provides a
supplementary heat source, if required. Refer to Section 4 for full
details on the electrical connections for the immersion heater.
The Grant Combined volumiser/low loss header also provides
a means for connection two Aerona³ heat pumps to be used
together on the same system. Whether one or two heat pumps
are used, they can be connected to either the right-hand or
left-hand side of the volumiser/header. However, if two heat
pumps are used, they must both be connected to the same side.
Refer to Sections 3.7 and 3.8 for further information of heat pump
and system connections.
The Grant Combined volumiser/ low loss header can be used as
a volumiser only, either using the factory-tted electric immersion
heater to provide a supplementary heat source or not, as required.
The Combined volumiser/low loss header is larger than normal for
a low loss header (e.g. 50mm, 75mm or 100mm diameter). This is
for two reasons:
a) To accommodate the 3kW immersion heater to provide a
supplementary heat source.
b) To minimise the internal turbulence that would normally
occur when the system mass ow of water exceeds that for
the primary heat pump circuit.
1 INTRODUCTION
Figure 1-1: Grant Combined volumiser/low loss header
1.2 CONSTRUCTION
The Grant Combined volumiser/low loss header is an insulated
rectangular tank tted with an integral 3kW electric immersion
heater. This is housed within a weatherproof external casing with
a removable cover at the top to access the electrical connections
and immersion heater.
It is designed to be located internally, xed to a wall using the
mounting brackets on the header.
The volumiser/header tank is a mild steel welded construction,
insulated with mineral wool, enclosed within an outer galvanised
steel casing with a white powder coated paint nish.
It has two groups of three pipe connections located on the
left-hand side of the unit and two groups of two pipe connections
on the right-hand side. All of these are 1” BSPF connections, refer
to Section 2 – Technical Data for further details on dimensions.
The unit is supplied with a manual air vent, to allow the volumiser/
header to be vented following lling, and a ½” drain cock, to allow
it to be drained down if required. Both are supplied loose to be
tted on site to their respective connections provided on the
right-hand side of the unit.
The 3kW electric immersion element is supplied, factory tted and
located inside a removable panel on the top of the unit. This can
be used provide a backup heat source, if required, controlled by
the Grant Aerona air source heat pump to which it is connected.
Refer to Section 4 – Electrical.
! WARNING !
The immersion heater must NOT be used unless it is fully
immersed in water, i.e. the volumiser/header is completely
lled and vented.
Always ensure that the electrical supply to the immersion
heater is isolated BEFORE draining down the volumiser/
header.
Also, ensure that volumiser/header is fully relled with
water and vented BEFORE switching the electrical supply
back on.
1.3 PRODUCT CONTENTS
The Grant Combined volumiser/low loss header is supplied with
the following items in a plastic bag located inside the top cover:
• 1 o󰀨 ¼” manual air vent
• 1 o󰀨 ½” drain cock
• 1 o󰀨 3/8” x ¼” reducing bush
• 4 o󰀨 1” blanking plugs
The following items are also supplied with the volumiser/header:
• 2 o󰀨 28mm isolating valves
• 1 o󰀨 Installation instructions.

Section 2: Technical data Page 5
Table 2-1: Volumiser/Low Loss Header technical data
Grant Combined Volumiser/Low Loss Header
Nominal capacity (litres) 11.5
Weight - empty (kg) 18.5
Weight - full (kg) 30.0
Inlet/outlet connections 1” BSP
Drain cock connection ½” BSP
Manual air vent connection ⅜” BSP
Materials
Shell Mild steel
Outer casing Galvanised mild steel, polyester powder coated
Insulation Mineral wool
Immersion Heater
Make Cotherm TSR
Output (kW) 3
Electrical supply 230V 50Hz 1ph
2.1 TECHNICAL SPECIFICATION
2 TECHNICAL DATA
2.2 DIMENSIONS
Figure 2-1: Grant Volumiser/Low Loss Header dimensions

Section 3: InstallationPage 6
3 INSTALLATION
3.1 GENERAL
This section gives details of the installation process for the Grant
Combined volumiser/low loss header with backup immersion
heater.
These installation instructions must be read in conjunction with
the Grant Aerona³ air source heat pump installation instructions
(provided with the heat pump).
Before starting any installation work on the Grant Aerona³ air
source heat pump and volumiser/low loss header, please read the
Health and Safety information given in Section 14 of the Aerona³
Installation Instructions.
3.2 REGULATIONS AND STANDARDS
The installation of the Grant Aerona³ air source heat pump and
the volumiser/low loss header must be in accordance with the
following recommendations, as applicable:
• Building Regulations for England and Wales, and Building
Standards for Scotland
• Local Bylaws (check with the Local Authority for the area)
• Water Supply (Water Fittings) Regulations 1999
• MCS Installer Standards (if applying for the Renewable Heat
Incentive)
• MIS3005 Requirements for contractors undertaking the
supply, design, installation, set to work, commissioning and
handover of microgeneration heat pump systems.
• MCS020 MCS Planning Standard
The installation should also be in accordance with the latest
edition of the following standards and Codes of Practice:
• BS7671 and amendments
• BS EN 12831
3.3 LOCATION
The Grant Combined volumiser/low loss header can be mounted
on any suitable wall surface capable of carrying the weight of the
unit when full of water and where the required clearances can be
achieved.
The unit MUST be installed vertically, with the immersion heater at
the top, as shown in Figure 2-1.
It MUST only be installed inside a property, and not located
externally, as it not designed to be weatherproof.
! NOTE !
The Grant volumiser/low loss header MUST NOT be
installed externally.
3.4 CLEARANCES
The Grant Combined volumiser/low loss header must be installed
such that adequate clearance is available for maintenance. In
particular, a suitable clearance of 300mm must be available
immediately above the unit to allow the removal and replacement
of the electric immersion heater.
Suitable clearance should also be allowed on the right-hand side
of the volumiser/header for access to, and the use of, the air
vent, drain cock, and any system isolating valves, as and when
required.
3.5 UNPACKING
The Grant Combined volumiser/low loss header is supplied
wrapped in bubble wrap with a separate kit of components
in a plastic bag located inside the top cover. Refer to list of
components given in Section 1.3 of these Instructions.
! NOTE !
Take care if cutting the bubble wrap with a knife not to
damage the volumiser/low loss header casing immediately
beneath.
3.6 INSTALLATION PROCEDURE
To install the Grant Volumiser/Low Loss Header:
1. Using a suitable thread sealant, t the ⅜” x ¼” reducing bush
into the ⅜” socket at the top of the right-hand side of the
volumiser/header and then t the ⅜” manual air vent into the
reducing socket. Refer to Figure 2-1. Position the air vent
such that the outlet is pointing downwards.
2. Again, using a suitable thread sealant, t the drain cock into
the ½” socket at the bottom of the right-hand side of the
header/volumiser. Refer to Figure 2-1. Position the drain cock
such that the outlet is facing downwards.
3. Position the volumiser/header with the back against the wall
on which it is to be mounted and mark the two xing centres
from both the top and bottom xing brackets.
4. Note that when lled with water, the volumiser/header will
weight 30kg. Ensure that the wall concerned is structurally
capable of carrying this weight.
5. Drill the wall to take suitable wall xings (not supplied) for
the type of wall construction and the weight of the volumiser/
header when full of water and t the wall xings.
6. Re-position the volumiser/header against the wall, align the
holes in the top and bottom xing brackets with the two wall
xings, and secure the header/volumiser to the wall with
screws.
! WARNING !
The immersion heater must NOT be used unless it is fully
immersed in water.
Always ensure that the volumiser/low loss header is full of
water BEFORE switching on the electrical supply.
3.7 HEAT PUMP FLOW AND RETURN
CONNECTIONS
The heat pump ow and return connections can be made to either
the right-hand or left-hand connections of the Grant Combined
volumiser/low loss header, but BOTH connections must be made
to the same side. Refer to Figures 3-1 and 3-2 for connection
details.
A second heat pump can also be connected to the volumiser/
header, but it must be connected to the same side as the rst heat
pump.
This second heat pump will operate as a ‘supplementary’ unit
controlled from the other ‘lead’ heat pump. Refer to Section 5 of
these instructions for the required parameter settings for both heat
pumps for this control conguration.
All unused connections should be sealed using the brass blanking
plugs provided.

Section 3: Installation Page 7
Heat pump 1 - Flow
Heat pump 2 - Flow
Heat pump 2 - Return
Heat pump 1 - Return
System Return
System Flow
System Flow
System Return
Second
Zone
Figure 3-1: Heat pump connections on left hand side
Heat pump 1 - Flow
Heat pump 2 - Flow
Heat pump 2 - Return
Heat pump 1 - Return
System Return
System Flow
Second
Zone
System Flow
System Return
Figure 3-2: Heat pump connections on right hand side

Page 8 Section 3: Installation
ISOLATION VALVES
Two 28mm isolating valves are supplied with the volumiser/
header. One of these must be tted in the system ow pipe and
the other in the system return pipe, close to where they are
connected to the header/volumiser.
FLOW REGULATOR
A ow regulator is supplied with the heat pump. This must be tted
in the return pipe from the volumiser/header to the heat pump.
Refer to Figure 3-3.
The ow regulator can be tted vertically or horizontally but must
be installed such that the arrow on the brass body points in the
direction of ow.
For an accurate and stable reading, ensure that there is straight
pipe of at least 5 times the pipe diameter (i.e. for 28mm pipe: 5 x
28mm = 140mm) before the inlet to the regulating valve.
During system commissioning, the ow regulator must be set to
the achieve the required ow rate in the primary circuit between
the heat pump and the volumiser/header.
The required ow rate will be dependent on the required
heat pump output (at design conditions) and the temperature
di󰀨erential between the heat pump ow and return.
This ow rate can be calculated as follows:
Flow rate = Heat output (kW) ÷ Temperature di󰀨erential (K)
÷ Specic heat capacity of water (4.2kJ/kgK) *
Example:
Heat output = 12kW
Di󰀨erential = 5K
Specic heat capacity of water = 4.2 kJ/KgK
Flow rate = 12 ÷ 5 ÷ 4.2 = 0.571 kg/sec
= 0.571 x 60 = 34.3 kg/min (or 34.3 litres/min)
! NOTE !
* The use of an antifreeze/inhibitor/biocide uid will alter
the value of Specic Heat Capacity but, as the di󰀨erence is
minimal, use 4.2kJ/kgK as a constant for the calculation of
ow rate.
To set the owrate, the system should be set to maximum
demand, i.e. with all emitters and zone valves open. The ow rate
is then adjusted by rotating the regulating valve until the required
ow rate is indicated on the ow regulator scale.
• To increase the ow rate - rotate valve anticlockwise
• To decrease the ow rate - rotate valve clockwise
The actual owrate must be read from the LOWER edge of the
oat, in the ow regulator window. Refer to Figure 3-3.
If two heat pumps of the SAME output are connected to the low
loss header/volumiser, both ow regulators should be set to the
SAME owrate, as calculated for the output of each heat pump.
If the two heat pumps are of DIFFERENT outputs:
a) Calculate the required ow rate for each heat pump, based
on their respective outputs.
b) Set the ow rate of each heat pump separately, i.e. with only
one heat pump operating at a time.
Figure 3-3: Flow regulator adjustment
Grant Aerona³ heat pumps are supplied with the circulating pumps
set to the highest of three possible performance curves. In order
to achieve the required ow rate it may be necessary to select
one of the other pump performance curves.
This is done by adjusting the setting of DIP switches DIP SW5
and DIP SW6 on the Terminal PCB of the heat pump. Follow the
guidance given in Section 8.3.6 of the Grant Aerona³ Installation
and Servicing instructions supplied with the heat pump
3.8 SYSTEM CONNECTIONS
The heating system ow and return connections can be made
to either the right-hand or left-hand connections of the Grant
Combined volumiser/low loss header, but BOTH connections
must be made to the opposite side of the volumiser/header to
the heat pump connections. Refer to Figures 3-1 and 3-2 for
connection details.
A second pair of system ow and return connections, i.e. for a
second zone, can also be connected to the volumiser/header,
but must be connected to the same side as the other system
connections. Refer to Figures 3-1 and 3-2 for connection details.
3.9 VOLUMISER ONLY CONNECTIONS
It is possible, if required, to use the Grant Combined volumiser/
low loss header as a volumiser only, either using the integral 3kW
immersion as a supplementary heater or not.
The volumiser/header must be tted in the ow pipe from the heat
pump as follows:
• The ow pipe from the heat pump should be connected to
lowest connection on either the right-hand or left-hand side of
the volumiser/header.
• The outlet pipe from the volumiser/header should be
connected should be connected to one of the upper set of
connections on either the right-hand or left-hand side of the
volumiser/header.
Refer to Figure 3-4.

Section 3: Installation Page 9
Flow from heat pump
Flow from heat pump
(Alternative position)
Flow to system
Flow to system
(Alternative positions) Flow to system
(Alternative position)
Figure 3-4: Volumiser only connections

Page 10 Section 4: Electrical
4 ELECTRICAL
! WARNING !
Electric shock may cause serious personal injury or death.
All electrical work must be undertaken by a competent person and
in accordance with the current edition of BS7671 (the I.E.T. Wiring
Regulations), including any amendments. Failure to observe this
legislation could result in an unsafe installation and will invalidate
all guarantees.
The equipment supplied must be wired according to these
Installation Instructions to ensure that the heat pump and
supplementary immersion heater function safely. All electrical
connections made on-site are solely the responsibility of the
installer.
4.1 GENERAL
The electric immersion heater is located at the top of the
volumiser/header and is accessed by undoing the four screws and
removing the sloping cover. Refer to Figure 4-1.
Figure 4-1: Location of immersion heater
If the immersion heater tted to the Grant Combined volumiser/
low loss header is to be used, it requires a 230V 50Hz single
phase electrical supply. Refer to Section 4.2 – Electrical
Connections.
In order for the immersion heater to be controlled by the Aerona³
as a supplementary heat source, the volumiser/header will also
need to be connected to the heat pump terminal PCB. Refer to
Section 4.2 – Electrical Connections.
4.2 ELECTRICAL CONNECTIONS
! WARNING !
Ensure that all electrical supplies to the heat pump and
volumiser/header are isolated before making any electrical
connections.
The immersion heater is supplied factory-tted in the volumiser/
header. However, check that it is securely tted before proceeding
with the electrical connections.
IMMERSION HEATER POWER SUPPLY
The immersion heater uses a dedicated power supply from a
correctly sized circuit breaker in the consumer unit. The nal
supply connection must be made from a 2-pole switch located
adjacent to the volumiser/header.
To connect this power supply to the electrical terminals in the
volumiser/header, refer to Figure 4-2 and proceed as follows:
1. Remove the access cover from the top of the volumiser/
header. To do this unscrew and remove the four screws and
remove the cover.
2. Feed the immersion heater supply cable through the upper
(larger) of the two cable glands on the left-hand side of the
volumiser/header and connect it to the LOWER immersion
heater electrical terminals as follows:
• Live to Terminal L (Brown terminal block)
• Neutral to Terminal N (Blue terminal block)
• Earth to Earth Terminal (Green terminal block)
Refer to Figure 4-3 for volumiser/header connection
diagram.
3. Tighten the cable gland to securely grip the cable.
Figure 4-2: Electrical connections

Section 4: Electrical Page 11
Figure 4-3: Connection diagram for Grant Combined Volumiser/Low Loss Header
IMMERSION HEATER CONTROL WIRING
The operation of the immersion heater as a supplementary heat
source is controlled by the Grant Aerona³ heat pump.
To connect the immersion heater control wiring to the electrical
terminals in the volumiser/header, refer to Figure 4-3 and proceed
as follows:
1. Connect a cable to the 230V output from the ‘Electric heater’
terminal (terminals 46 and N) on the Aerona³ Terminal PCB.
2. Pass this cable through the lower (smaller) of the two cable
glands on the left-hand side of the header/volumiser and
connect it to the UPPER electrical terminals as follows:
• Terminal 46 on heat pump terminal PCB to Terminal L
(A2 on the backup heater relay)
• Terminal N on heat pump Terminal PCB to Terminal N
(A1 on the backup heater relay)
Refer to Figure 4-3 for header/volumiser connection
diagram.
3. Tighten the cable gland to securely grip the cable.
4.3 IMMERSION HEATER
The Grant Combined volumiser/low loss header is supplied
factory-tted with a pre-wired 3kW Cotherm Type TSR immersion
heater to provide a supplementary heat input if required.
! WARNING !
This immersion heater must NOT be used unless it is fully
immersed in water. Always ensure that the volumiser/
header is full of water BEFORE switching on the electrical
supply.
The immersion heater control thermostat is pre-set on position 4
at a temperature of approximately 65°C. This can be adjusted as
required. Refer to Figure 4-4.
= Earth (Green/Yellow)
= Live (Brown)
= Neutral (Blue)
Temperature
control dial
Reset
Figure 4-4: Immersion heater wiring connections
The wiring connections are also shown in Figure 4-4. Follow
the wiring instructions connecting the live, neutral and earth as
indicated.

Page 12 Section 4: Electrical
OVER-TEMPERATURE CUT-OUT
This immersion heater is tted with a Cotherm type TSR
thermostat that incorporates an independent non-self-
resetting over-temperature cut-out to prevent excessive water
temperatures.
The reset pin is located in a small opening to the side of the
control dial and indicated by small triangle with the word ‘safety’.
Refer to Figure 4-4.
In normal operation the reset pin will be approximately 2-3mm
below the surface of the plastic thermostat housing.
Should the over-temperature cut-out operate, the reset pin will be
pushed up to become level or slightly above the surface of the
housing.
To reset the over-temperature cut-out:
• Isolate the volumiser/header and immersion element from the
mains electrical supply.
• Wait for the temperature in the volumiser/header to fall
su󰀩ciently.
• Using a suitably sized implement, push the reset pin using
hand pressure only to return it to its normal operating
position.
! WARNING !
Ensure the volumiser/header and immersion heater is
isolated from the mains before attempting to reset to
over-temperature cut-out.
If the immersion heater needs to be replaced it must be tted to
the volumiser/header using the gasket provided on the unit. Only
use a correctly shaped spanner. Stilsons or pipe grips should NOT
be used. The use of sealing compound is not recommended.
! WARNING !
Always ensure that the immersion heater cap is not
covered.
4.4 ELECTRICAL CONNECTIONS BETWEEN
LEAD AND SUPPLEMENTARY HEAT
PUMPS
When using two Aerona³ heat pumps connected to the volumiser/
header, one of the two (the supplementary unit) will be controlled
by the other (the lead unit).
The lead unit can be used to provide both Heating and DHW, but
the supplementary unit will be used only for Heating.
Refer to Figure 4-5 below for details of the electrical connection
between the two heat pumps.
Scale: NTS
Paper Size: A4
Project Title: Aerona³ ASHP Lead to Back-up unit connection details
Drawing Set: Aerona³ Wiring Schematics
Status: Approved
Rev Date: 20/01/22 Drawn By: CG Checked By: PS & NS
Dwg. No. HPWS0026
Revision: 1.1
This drawing and its content is subject to copyright. Use other than for its original intended purpose must be arranged with an employee of Grant UK Ltd.
Hopton House, Hopton Industrial Estate, Devizes, Wiltshire, SN10 2EU, tel; 01380 736920
Revision Details:
1.1 20/01/22 Approved
ASHP Terminals
N
41
42
43
44
51
52
45
46
47
48
49
50
N.C.
- Lead Unit -
ASHP Terminals
1
2
3
4
5
6
7
8
17
18
19
20
21
22
23
24
25
Aerona ³
Heat Pump
3 2 1
1 2 3 4
RL1 RL2
RL3
DHW
N
P
CH
Grant EP002 Heat Pump Interface
Common (Red)
Link Heating (Blue)
Grant Aerona³ ASHP
Remote Controller
- Supplementary Unit -
Aerona ³
Heat Pump
Figure 4-5: Wiring connections between lead and supplementary heat pumps

Section 5: Operation Page 13
5 OPERATION
5.1 GENERAL
Before starting to commission the installation, including the
Aerona³ air source heat pump, must be completed as detailed in
Sections 3 and 4 of these instructions.
! NOTE !
In order to commission the installation, the following
information must be used in conjunction with the Aerona³
installation instructions supplied with the heat pump.
5.2 AERONA³ HEAT PUMP PARAMETER
SETTINGS
Switch on the power to the heat pump, via the external isolator.
Press and hold the ON/OFF button on the heat pump remote
controller for three seconds to turn the heat pump on – refer to
Aerona³ installation instructions Section 9.1.
Set the day and time on the heat pump remote controller – refer to
Aerona³ installation instructions Section 9.2
Access the heat pump parameter setting menus via the heat
pump remote controller – refer to Aerona³ installation instructions
Section 9.3
If the factory-tted electric immersion heater is to be used as
a back-up heater refer to Section 5.3 for the correct parameter
settings.
If a second Grant Aerona³ heat pump is to be used, refer to
Section 5.5 for the correct parameter settings for the operation of
a supplementary heat pump
5.3 PARAMETER SETTINGS FOR SUPPLEMENTARY IMMERSION HEATER OPERATION
Set the parameters as detailed in the table below.
Table 5-1: Aerona³ heat pump parameter settings for supplementary immersion heater operation
Level Parameter Function description Display and input value
Group Code Default Min. Max. Setting
I 46 00
Backup heater type of function
0 = disable
1 = Replacement mode
2 = Emergency mode
3 = Supplementary mode
0 0 3 3
I 46 01 Manual water set point 50°C 40 55 55
I 46 04 Heater activation delay time 5 mins 0 900 0
I46 05 Integration time for starting heaters 600 0 900 0
I 46 13 Outdoor air temp to enable backup
heaters (supplemantary mode) 5.0°C -20.0 +20 5
I 46 14 Outdoor air hysteresis to disable
Backup heaters 5.0°C 0.5 10.0 2
I51 46
Terminal 46: DHW electric heater or
Backup heater
0 = DHW electric heater
1 = Backup heater
0 or 1 0 1 1
! NOTE !
Refer to the Aerona³ installation instructions, supplied with
the heat pump, for further details on how to access and
adjust the above heat pump parameters.

Page 14 Section 5: Operation
Set the parameters as detailed in the table below.
Table 5-2: Aerona³ heat pump parameter settings for assisting defrost process
Level Parameter Function description Display and input value
Group Code Default Min. Max. Setting
I 46 00
Backup heater type of function
0 = disable
1 = Replacement mode
2 = Emergency mode
3 = Supplementary mode
0 0 3 3
I 46 20
Freeze protection functions
0 = disable
1 = enabled during start-up
2 = enabled during Defrost
3 = enabled during start-up and Defrost
0 0 3 2
I 46 23 Outgoing water set point during Defrost 24 10 50 30
I51 46
Terminal 46: DHW electric heater or
Backup heater
0 = DHW electric heater
1 = Backup heater
0 or 1 0 1 1
! NOTE !
Refer to the Aerona³ installation instructions, supplied with
the heat pump, for further details on how to access and
adjust the above heat pump parameters.
5.4 PARAMETER SETTINGS FOR ASSISTING
DEFROST PROCESS
Depending on the overall system volume in place at the time
of the defrost, it may be useful energising the supplementary
immersion heater tted to the Grant Combined volumiser/low loss
header to assist the defrost process.
The overall time for a defrost should never be more than 5
minutes (including the compressor protection ‘o󰀨’ time of 3
minutes) so the total power used during a defrost period by the
immersion element would not be more than 250W.
After the defrost function is completed, the immersion heater will
switch o󰀨 when the ow temperature has reached the minimum
ow target temperature (Parameter 46 23) + 5ºC
5.5 PARAMETER SETTINGS FOR LEAD / SUPPLEMENTARY HEAT PUMP OPERATION
Set the parameters as detailed in the table below.
Table 5-3: Lead heat pump settings
Level Parameter Function description Display and input value
Group Code Default Min. Max. Setting
I 46 00
Backup heater type of function
0 = disable
1 = Replacement mode
2 = Emergency mode
3 = Supplementary mode
0 0 3 3
I 46 01 Manual water set point 50°C 40 55 55
I 46 04 Heater activation delay time 5 mins 0 900 0
I46 05 Integration time for starting heaters 600 0 900 0
I 46 13 Outdoor air temp to enable backup
heaters (supplemantary mode) 5.0°C -20.0 +20 10
I 46 14 Outdoor air hysteresis to disable
Backup heaters 5.0°C 0.5 10.0 2
I51 46
Terminal 46: DHW electric heater or
Backup heater
0 = DHW electric heater
1 = Backup heater
0 or 1 0 1 1
! NOTE !
Refer to the Aerona³ installation instructions, supplied with
the heat pump, for further details on how to access and
adjust the above heat pump parameters.

Section 5: Operation Page 15
Table 5-4: Supplemantary heat pump settings
Level Parameter Function description Display and input value
Group Code Default Min. Max. Setting
I 21 00
Enable outgoing water set point
0 = Fixed set point
1 = Climatic curve
1 0 1 0
I 21 01 Fixed outgoing water set point 45°C 23.0 60.0 55
! NOTE !
Refer to the Aerona³ installation instructions, supplied with
the heat pump, for further details on how to access and
adjust the above heat pump parameters.

GRANT ENGINEERING (UK) LIMITED
Hopton House, Hopton Industrial Estate, Devizes, Wiltshire, SN10 2EU
Tel: [phone] Fax: [phone]
Email: [email protected] www.grantuk.com