Heatrae Sadia HI-MAX INSTANT ID 5-60 Installation, Operation And Maintenance Manual page 41

Table 6: Fault fi nding chart continued...
Fault
Intermittently:
Check gas charge in expansion vessel.
Water discharges
Continually:
from expansion
Cold water pressure reducer not working correctly.
relief valve
Expansion relief valve seat damaged.
Oxygenated water.
Opaque water
Controller incorrectly set, faulty, or wired incorrectly. Check controller settings, wiring and is operating correctly.
Room thermostat set wrong, faulty, or wired
incorrectly.
Isolation valves in closed position.
Strainer blocked.
Community heating control valve seized, blocked,
faulty, fi tted or wired incorrectly.
No heat from the community heating system.
No Heating
Check heating PICV isn't seized, faulty, or wired
incorrectly.
Low system pressure
Pump not running
No power to the controller / heating system.
Controller incorrectly set, faulty, or wired incorrectly. Check controller settings, wiring and is operating correctly.
Room thermostat set wrong, faulty, or wired
incorrectly.
No heating and
Community heating control valve seized, blocked,
hot water
faulty, or wired incorrectly.
No heat from the community heating system.
Strainer blocked.
Isolation valves in closed position.
Low district heating fl ow temperature.
Low district heating fl ow rate.
Insuffi cient
heating and hot
water
No community heating fl ow to the unit.
Distribution pumps not set correctly or
under sized.
Possible Cause Remedy
See Maintenance section (page 39) for
re-charging the expansion vessel procedure.
Check pressure from cold water PRV. If greater than 3.0
bar replace pressure reducing valve cartridge.
Remove expansion relief valve cartridge, check condition
of seat. If necessary fi t new expansion relief valve.
Water from a pressurised system releases oxygen
bubbles when fl owing. The milkiness will disappear after
a short while.
Check room thermostat settings, wiring and is operating
correctly.
Ensure all isolation valves are open.
Remove and clean strainer mesh fi lter.
Check valve wiring and is operating correctly. Check pipe
temperature either side of the valve. Check actuator
is operational. Remove and clean if necessary. Check
orientation and wiring.
Check the community heating system
Check PICV wiring and that the valve is operating correctly.
Check system pressure and top up as necessary.
Check pump is operating correctly.
Check light around red control knob, if the light is off it
indicates there is no power to the pump.
Check light around red control knob, if the light is fl ashing
red and green it indicates a voltage supply fault or the
pump is over heating.
Check light around red control knob, if the light is fl ashing
red it indicates the pump is faulty and requires changing.
Check power supply / fuse / circuit breaker.
Check cylinder and room thermostat settings, wiring and
is operating correctly.
Check valve wiring and is operating correctly. Check pipe
temperature either side of the valve. Check actuator is
operational. Remove and clean if necessary.
Check the community heating system
Remove and clean fi lter.
Ensure all isolation valves are open.
Check district fl ow pipe temperature / heat
meter temperatures. Check
temperature settings and boiler size.
Using a manometer, check pressure drop across district
control valve to verify fl ow rate. Check and clean strainer,
isolation valves and district control valve. Check the pipe
sizing.
Using a manometer, check pressure drop across district
control valve to verify fl ow rate. Check and clean strainer,
isolation valves and district control valve. Check the pipe
sizing.
Check strainer isn't blocked, check isolation valves and
district control valve are fully open.
Check district heating pumps.
central boiler fl ow
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