When carrying out any repair work on the HIU the unit must be switched off and isolated!
Always isolate the power supply before opening the unit!
Ref
REPORTED PROBLEM
Trouble Shooting Checklist
3
Reported problem;
•
Insufficient Hot Water at the taps, but no error codes at the
Controller
If all checks prove the HIU is working correctly,
•
Is there a bypass fitted on the primary before the HIU,
and it has been left open? CLOSE the valve, the HIU will
now work as designed.
•
Is the TMV set at the correct temperature? Has it been
tampered with or reset in error? Set to 57C
•
Is there enough FLOW at the HIU? If the supply pumps
have not been designed to the required flow of the HIU,
then DHWS will not be sufficient
•
Similar for pipework, if not sized correctly, the HIU will
not be able to deliver to its designed output
4
Reported problem;
•
No Room Heating
•
Radiators are COLD.
•
Under Floor Heating is installed Floor is COLD.
•
No Room Heating or Hot Water
•
Check the ambient temperature. Is the reason that the
room thermostat setting is too low to switch on the
heating?
•
system low pressure. Has the safety valve discharged?
Check system pressure and top up if necessary.
•
Check the Circulating Pump (see LED lights on the pump
which can warn of a problem or a fault). Is the pump fully
operational?
•
Is the controller set up correctly? See Installer settings
•
Is the Room thermostat wired correctly? Is it working?
•
Check that the communal heating is supplying heat to the
unit
•
Check then that the isolation valves to the unit are open.
•
Is the Bypass Valve open on the valve above the HIIU?
5
Reported problem;
•
The Control mode seems to be stuck in either Heating or Hot
water function, and wont change even if either the room stat
or flow switch is disconnected.
•
A PCB in the Controller is damaged. Look for the cause
first before replacing. Usual suspect is that a 230v supply
has been connect in error to a zero volt connection,
either the T1 / T2 connection for the room stat or on the
AUX plug for pre
-
payment connection
6
Reported problem;
•
Suspect colouration of the water from the Hot Taps
•
Check a water sample from the cold main supply, is this
the cause?
If the water seems slightly
‘
milky
’,
the cause of this is simply
the aeration of the water. Once the oxygen has been released
the water will clear of its own accord.
For persistent and extreme contamination check the Plate
Heat Exchanger for signs of cross contamination
SECTION 9
-
Installation and Assembly instructions
-
TROUBLE SHOOTING
09/17 E & OE
Summary of Contents for Hiper Xi45 INDIRECT HIU 45DHW/10HTG
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