Ideal Heating POD HIU User manual

When replacing any part on this appliance, use only spare parts that you can be assured conform to the safety and performance
specication that we require. Do not use reconditioned or copy parts that have not been clearly authorised by Ideal Heating.
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April 2021
UIN 224647 A01
USER
INSTRUCTIONS
POD HIU
HEATING

2User Instructions
CONTENTS
1. Introduction....................................................3
1.1 Safety ..........................................................3
1.2 Electrical Supply..........................................3
1.3 Important Notes...........................................3
2. HIU Operation................................................4
3. System Water Pressure.................................6
4. General Information.......................................7
5. Points for the HIU User..................................7
6. Troubleshooting.............................................8
7. Display Functions - Normal Operation...........8
8. Display Functions - Fault Messages..............10

3
User Instructions
1 INTRODUCTION
The Ideal POD HIU is a wall mounted, electronically controlled
Heat Interface Unit (HIU) for use with district or community
heating systems, available in Indirect or Direct models.
Domestic Hot Water (DHW) output is fully modulating with a
maximum of:
• 30, 40, 50, 60 or 70 kW for Indirect units
• 30, 40, 50 or 60 kW for Direct units.
Central Heating (CH) output is also fully modulating with a
maximum of:
• 5 kW for all models.
The HIU is supplied fully assembled with DHW plate heat
exchanger and Pressure Independent Control Valves (PICVs.)
Indirect versions also include a plate heat exchanger, circulating
pump, pressure gauge, safety valve and expansion vessel
within the CH circuit. There are also optional extras available for
the HIU such as heat meters and Credit Control valves (CCVs.)
Please see the installation manual for full list of option kits.
1.1 SAFETY
CURRENT SAFETY (INSTALLATION & USE) REGULATIONS
OR RULES IN FORCE
The HIU must be installed by a competent person trained in
Heat Network product installations, in accordance to Heat
Network code of practice (installation and use) regulations or
other rules in force.
The appliance is suitable only for installation in GB and IE and
should be installed in accordance with the rules in force.
It must be carried out in accordance with the relevant
requirements of the:
• Heat Networks code of practice (Installation and Use)
Regulations.
• Appropriate Building Regulations, either. The Building
Regulations (England and Wales), The Building Regulations
(Scotland), Building Regulations (Northern Ireland).
• Water Fittings Regulations or Water byelaws in Scotland.
Current I.E.E. Wiring Regulations.
Where no specic instructions are given, reference should be
made to the relevant British Standard Code of Practice.
The current Building Regulations and reference should be made
to the current ETCI rules for electrical installation.
Detailed recommendations are contained in the following British
Standard Codes of Practice:
CIBSE CP1 (2020) Heat Network code of practice.
BS EN 12828 Heating Systems in buildings: Design for water-
based heating systems.
BS EN 12831 Heating Systems in buildings: Method for
calculation of the design heat load.
BS EN 14336 Heating Systems in buildings: Installation and
commissioning of water-based heating systems.
BS 6891 Low pressure installation pipes.
Health & Safety Document No. 635.
The Electricity at Work Regulations, 1989.
It is essential that the instructions in this booklet are strictly
followed, for safe and economical operation of the HIU.
1.2 ELECTRICITY SUPPLY
This appliance must be earthed.
Supply: 230 V ~ 50 Hz. The fusing should be 3A.
Wiring external to the appliance MUST be in accordance with
the current I.E.E. (BS 7671) Wiring Regulations and any local
regulations which apply. For IE reference should be made to the
current ETCI rules for electrical installations.
The mains supply to the HIU and system wiring centre shall be
through one common fused double pole isolator and for new
heating systems, and where practical replacement installations,
the isolator shall be situated adjacent to the appliance.
1.3 IMPORTANT NOTES
• This appliance must not be operated without the casing
correctly tted.
• If the HIU is installed in a compartment then the
compartment must be well ventilated and not used for
storage purposes.
• If it is known or suspected that a fault exists on the HIU
then it MUST NOT BE USED until the fault has been
corrected by a qualied engineer.
• Under NO circumstances should any of the sealed
components on this appliance be used incorrectly or
tampered with.
• This appliance can be used by children 8 years and above.
Also, persons with reduced physical, sensory or mental
capabilities, or lack of experience and knowledge, provided
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.

4User Instructions
2 HIU OPERATION
CONTROLS DIAGRAM
TO START THE HIU
If a programmer is tted refer to separate instructions for the programmer before continuing.
Start the HIU as follows:
1. To switch the domestic hot water and central heating on and off or adjust the target temperatures use the Menu button (D) to
navigate the status display (E).
2. In the ‘off’ mode the HIU will display the following:
3. From normal operation screen press the Menu button to access the DHW target temperature setting menu.
4. The DHW target temperature can now be adjusted by pressing the +/- buttons within the installer dened limits.
A B C D
E
F
G
Legend
A. Reset Button
B. - Function Button
C. + Function Button
D. Menu Button
E. HIU Status Display
F. CH System Pressure Gauge (Indirect Only)
G. Heat Meter (Optional)
HOT WATER
PREHEAT
OFF
- -
60
ºC
HIU Off Mode

5
User Instructions
5. Press the Menu button again to access the CH target temperature setting menu.
6. The CH target temperature can now be adjusted by pressing the +/- buttons within the installer dened limits.
Note: If using underoor heating ensure CH target temperature is within the safe operating temperature for the
underoor heating.
7. Press the Menu button again to access the CH state setting menu.
8. Press the +/- buttons to either enable or disable the CH operation.
9. Press the Menu button again to access the DHW state setting menu.
10. Press the +/- buttons to either enable or disable the DHW operation.
11. Press the Menu button again to access the DHW preheat state setting menu.
12. Press the +/- buttons to either enable or disable the DHW preheat operation
13. Press the Menu button again to return to normal operation.
If the HIU displays a fault, please refer to the troubleshooting section.
45
ºC
ON
OFF
ON
OFF
HOT WATER
PREHEAT
ON
HOT WATER
PREHEAT
OFF
- +/-
- +/-
- +/-
- -/+
- -/+
- -/+

6User Instructions
3 CH SYSTEM WATER PRESSURE (INDIRECT MODELS ONY)
The system pressure gauge (see page 4) indicates the central
heating system pressure. If the pressure is seen to fall below
the original installation pressure of 1-2 bar over a period of time
and continues to fall then a water leak may be indicated. In this
event re-pressurise the system as shown below. If unable to do
so or if the pressure continues to drop an Approved Engineer
should be consulted.
THE HIU WILL NOT PROVIDE CH IF THE PRESSURE
HAS REDUCED TO LESS THAN 0.3 BAR UNDER THIS
CONDITION.
Filling CH / Topping up (Indirect Ony)
1. Ensure isolation valves A, E and F are in the “run” position
(handle vertical) and isolation valve G is in the “off” position
(handle opposing body).
2. Remove the dust cap from valve A and plug from the lling
loop adjacent to valve A.
3. Ensure top hat washers is still tted to the valve A (if not
then check inside the removed dust cap).
4. Connect the lling loop to valve A.
Note: Heat Interface Unit not shown for clarity
5. Turn isolation valve A to the “ll” position (handle
horizontal).
6. Turn valve G to the “ll” position (handle in line with valve
body). The CH circuit will begin to ll.
7. Monitor the pressure gauge until the correct pressure is
achieved (max 2.75 Bar, recommended 1 – 1.5 bar for
normal operation) then turn isolation valve G to the “off”
position (handle opposing valve body) to isolate the charge
supply.
Note: If relling the unit or system rather than topping
up, air may require manual venting from the CH circuit by
a certied agent. Refer to the installation and servicing
instructions for more information.
8. Turn isolation valve A to the “run” position (handle vertical).
9. Remove the lling loop hose from valve A. Insert storage
plug into left side of lling loop hose.
Note: A small volume of water may remain within the hose.
10. Ensure top hat washer is still attached to isolation valve A.
11. Screw the dust cap to the front of isolation valve A.
AGF
E
A
B
C
D
E
G
F
AE
G
F
Filling Loop Hose
1
0
2
3
4
bar

7
User Instructions
4 GENERAL INFORMATION
HIU PUMP (INDIRECT ONLY)
The HIU pump will operate briey as a self-check once every
24 hours, regardless of system demand.
MINIMUM CLEARANCES
Clearance of 100 mm above, 80 mm below the bottom of wall
bracket, 20 mm at the sides and 600mm at the front of the HIU
casing to allow for servicing.
CLEANING
For normal cleaning simply dust with a dry cloth. To remove
stubborn marks and stains, wipe with a damp cloth and nish
off with a dry cloth. DO NOT use abrasive cleaning materials.
MAINTENANCE
The appliance should be serviced at least once a year by an
approved engineer.
5 POINTS FOR THE HIU USER
Note: In line with our current warranty policy we would ask that you check through the following guide to identify any
problems external to the HIU prior to requesting a service engineers visit. Should the problem be found to be other
than with the appliance we reserve the right to levy a charge for the visit, or for any pre-arranged visit where access is
not gained by the engineer.

8User Instructions
7 DISPLAY FUNCTIONS - NORMAL OPERATION MODE
Note: The temperatures shown below are for illustration purposes only.
The measured temperatures will be shown on the HIU.
HOT WATER
PREHEAT
OFF
00
HOT WATER
PREHEAT
OFF
- -
Summer Mode, DHW enabled and no heat demand:
HIU ‘Off’ Mode:
6 TROUBLESHOOTING
No Hot Water No Central Heating No Hot Water or
Central Heating
Check the mains
power is turned
on and if a CCV is
installed the HIU has
credit.
Check the mains
power is turned
on and if a CCV is
installed the HIU has
credit.
Check the mains
power is turned
on and if a CCV is
installed the HIU has
credit.
Is DHW
enabled on the
user interface?
Is CH enabled
on the user
interface?
Does the HIU
have a display
showing on
the front
control panel?
Enable DHW
as described
in section 2.
Enable CH as
described in
section 2. See HIU ‘Display
Functions’
section.
Is cold water coming
out of the hot tap
when turned on?
Check the
programmer
(internal or external
to the HIU) is in an
‘ON’ position and
the room thermostat
is turned up. Check
the time settings on
the programmer are
correct.
See HIU ‘Display
Functions - Fault
messages’ section.
Is heating
functional?
Contact a registered
engineer or the
person responsible
for managing your
water supply.
Contact a registered
engineer or the
person responsible
for managing your
water supply.
Contact a registered
engineer or the
person responsible
for managing your
water supply.
NO NO
YES
YES YES
NO NO
NO
NO
YES
CCV = Credit Control Valve

9
User Instructions
DISPLAY FUNCTIONS - NORMAL OPERATION MODE CONT’D
HOT WATER
PREHEAT
OFF
43
ºC
HOT WATER
PREHEAT
OFF
43
ºC
HOT WATER
PREHEAT
ON
ph
ºC
HOT WATER
PREHEAT
OFF
43
ºC
HOT WATER
PREHEAT
OFF
fp
ºC
HOT WATER
PREHEAT
OFF
00
HIU frost protection - will alternate with the current frost protection temperature:
HIU hot water preheating - will alternate with the current DHW temperature:
Summer Mode, DHW enabled with heat demand:
Winter Mode, DHW and CH enabled, no heat demand:
Winter Mode, with DHW heat demand:
Winter Mode, with CH heat demand:

10 User Instructions
8 DISPLAY FUNCTIONS - FAULT MESSAGES
Display Fault Action
HOT WATER
PREHEAT
OFF
F1
Low Water
Pressure
Check system water pressure is between 1 and 1.5 bar on the system
pressure gauge. To re pressurise the system see section 3. If HIU
continues to show fault, please contact Ideal (if under warranty) or
contact a suitable qualied service engineer.
HOT WATER
PREHEAT
F2
OFF
No change in DHW
Temperature during
demand period
Check primary circuit is fully open and all isolation valves at base of HIU
are open. If a CCV (credit control valve) is installed in appliance, ensure
dwelling has sufcient credit. Reset the appliance – If HIU continues to
show fault please contact Ideal (if under warranty) or contact a suitable
qualied service engineer.
HOT WATER
PREHEAT
OFF
f4
Flow Thermistor
Fault
Reset the appliance – If HIU continues to show fault please contact
Ideal (if under warranty) or contact a suitable qualied service engineer.
HOT WATER
PREHEAT
F5
OFF
Return Thermistor
Fault
Reset the appliance – If HIU continues to show fault please contact
Ideal (if under warranty) or contact a suitable qualied service engineer.
HOT WATER
PREHEAT
F6
OFF
Outside Sensor
Open Circuit
Power down appliance and check wiring between outside sensor and
HIU if outside sensor location is known. Reset the appliance – If HIU
continues to show fault please contact Ideal (if under warranty) or
contact a suitable qualied service engineer.
HOT WATER
PREHEAT
F7
OFF
Incorrect Mains
Voltage
Contact a qualied electrician, the building manager, or the electricity
provider.

11
User Instructions
DISPLAY FUNCTIONS - FAULT MESSAGES CONT’D
Display Fault Action
HOT WATER
PREHEAT
f8
OFF
Primary Thermistor
Fault
Reset the appliance – If HIU continues to show fault please contact
Ideal (if under warranty) or contact a suitable qualied service engineer.
HOT WATER
PREHEAT
F9
OFF
PCB Fault Uncongured/Faulty PCB. Please contact Ideal (if under warranty) or
contact a suitable qualied service engineer.
HOT WATER
PREHEAT
L9
OFF
PCB Fault Uncongured/Faulty PCB. Please contact Ideal (if under warranty) or
contact a suitable qualied service engineer.
HOT WATER
PREHEAT
fp
OFF
Pump Failure
Check system water pressure is between 1 and 1.5 bar on the system
pressure gauge. Reset the appliance – If HIU continues to show fault
please contact Ideal (if under warranty) or contact a suitable qualied
service engineer.
HOT WATER
PREHEAT
fc
OFF
DHW Thermistor
Fault
Reset the appliance – If HIU continues to show fault please contact
Ideal (if under warranty) or contact a suitable qualied service engineer.
HOT WATER
PREHEAT
F
OFF
OpenTherm Plus
Fault
Check connection between smart thermostat and HIU. Refer to Smart
thermostat fault nding. Reset the appliance – If HIU continues to
show fault please contact Ideal (if under warranty) or contact a suitable
qualied service engineer.

Ideal is a trademark of Ideal Boilers.
Registered Ofce
Ideal Boilers Ltd., National Avenue, Hull, East Yorkshire, HU5 4JB
Tel [phone] Fax [phone]
Registration No. London 322 137
Ideal Commercial Technical Helpline: 01482 498376
Ideal Parts: 01482 498665
idealheating.com
Ideal Boilers Ltd., pursues a policy of continuing improvement in the design and performance of its products.
The right is therefore reserved to vary specication without notice.
HEATING
Technical Training
Our Expert Academy offer a range of training options designed and delivered by our experts in heating.
For details please contact:
expert-academy.co.uk
At Ideal Heating we take our environmental impact seriously, therefore when installing any Ideal Heating product please make sure to dispose of any
previous appliance in an environmentally conscious manner. Households can contact their local authority to nd out how.
See https://www.gov.uk/managing-your-waste-an-overview for guidance on how to efciently recycle your business waste.
Manufactured under
an ISO 9001
registered quality
management system
FM 59915