User guide
27
Symptom Cause  Remedy
Maximum water 
temperature too 
hot or cold.
Maximum water temperature 
set incorrectly.
Reset maximum water 
temperature. Refer to ‘Maximum 
Temperature Setting’ in 
Commissioning section (page 22) 
and ‘Adjusting the Temperature’ 
in Maintenance section (page 23).
Outlet water 
temperature too 
hot / cold.
Inlet filter is partially blocked. Check insert filters for any 
blockages and clean as 
necessary.
Installation conditions outside 
operating parameters.
Refer to Installation Requirements 
section (pages 6-10).
Service shower valve as 
recommended. Refer to 
Maintenance section (page 23).
Refer to Adjusting the 
Temperature section (page 24).
Water 
temperature 
too cold - 
maximum water 
temperature 
incorrectly set.
Hot water temperature is less 
than 10˚C above the required 
blend temperature.
Adjust hot water temperature or 
wait for water to reheat if stored 
system is used.
Instantaneous water heater 
not igniting because water flow 
rate is too low.
Increase water flow rate through 
the system.
Check cartridge inlet filters 
and clean or replace. Refer to 
Maintenance section (page 23). 
Contact the boiler manufacturer.
Instantaneous water heater 
not igniting because water 
pressure is too low.
Increase water pressure through 
system. 
Contact the boiler manufacturer.
Only hot or cold 
water from 
shower valve 
outlet.
Inlet water supplies are 
reversed (hot to cold supply).
Check the connections are the 
correct way round. Hot on the 
left and cold on the right when 
viewed from the front. Rework 
pipework as necessary.
Inlet filter is partially blocked. Clean or replace, flush through 
pipework before refitting.
Troubleshooting - cont. 










