Troubleshooting; Fault Fi Nding - Heatrae Sadia HI-MAX INSTANT ID 5-60 Installation, Operation And Maintenance Manual

10. Troubleshooting

WARNING
Do not tamper with any of the safety valves
or controls supplied with the HIU as this will
invalidate any guarantee.
10.1 Fault fi nding

Important
 After servicing, complete the relevant Service
Interval Record section of the Benchmark
Checklist located on pages 54 of this book.
 Servicing should only be carried out by
competent persons in the installation and
maintenance of hydraulic interface units and
district heating systems.
 Any spare parts used MUST be a Heatrae Sadia
authorised parts.
Disconnect the electrical supply before removing

the casings and any electrical equipment covers.
NEVER operate system without the necessary

safety valves and devices.
Table 6: Fault fi nding chart
Fault
No hot water fl ow
Water from hot tap
is cold
Water temperature
from hot tap
unstable
40
Possible Cause
No cold water supply
Cold water supply off
Filter blocked
Cold water control valves incorrectly fi tted
Controller incorrectly set, faulty, or wired
incorrectly.
PICV valve blocked or faulty.
Diverter stuck in bypass or heating mode.
No heat from the community heating system. Check the community heating system.
Community heating fl ow strainer blocked.
Isolation valves in closed position.
Incorrectly piped.
DHW plate heat exchanger blocked.
Stv hot port blocked or Stv has been tampered
with or faulty.
The unit doesn't sense fl ow.
Heat Meter blocked.
Faulty Stv safety device.
Faulty controller.
Faulty sensor.
Incorrect PID settings in the controller.
WARNING
Water contained in the HIU may be
very hot, especially following a thermal
control failure. Caution must be taken
when draining water from the unit.
The fault fi nding chart (Table 6, below) will enable
operational faults to be identifi ed and their possible
causes rectifi ed.
In case of doubt contact service support (see contact
details on page 56).
Spare Parts
A full range of spare parts are available for the
unit (see Table 8, page 51). Refer to the technical data
label on the unit to identify the model installed and
ensure the correct part is ordered. You will need to
quote the serial number that is printed on the unit's
data label, which can be found on the back plate
behind the controller.

If a fault code is displayed on the
controller refer to the fault codes in Table 7 on
page 42 and 43 for details.
Remedy
Check that there is cold water to the property
Check and open stop cock
Turn off water supply. Remove fi lter and clean
Check and refi t as required
Check controller settings, wiring and is operating correctly.
Check pipe temperature either side of the valve.
Check actuator is operational.
Check valve, remove and clean as necessary.
Check the temperature at the diverter outlets.
Remove diverter and check valve and diverter operation.
Replace the actuator or diverter valve.
Remove and clean strainer mesh fi lter.
Ensure all isolation valves are open.
Check piping.
Check community heating side of plate heat exchanger
and clean or replace as necessary.
Check the Stv setting and for blockage and clean or replace
as necessary.
Ensure that the tap icon comes up on the display. Increase
the fl ow of water to the hot tap or replace the fl ow sensor
as necessary.
Check that the heat meter isn't blocked and replace as
necessary.
Check Stv and replace as necessary.
Check controller and replace as necessary.
Check calibration of the sensor and replace as necessary.
Check PID settings in the controller - contact Heatrae Sadia
for advice.