Operating instructions
Inst.241a Viron Series Pool & Spa Heater V08.11
6
DISPLAY SYMBOL INDICATION
Under fault conditions the thermostat will display a set of alpha numeric symbols to indicate the status of the
heater. The meaning of each symbol and action to be taken are listed as follows:
SYMBOL MEANING ACTION
Temp Display Unit has power. No action.
F0 Heater locked off, thermistor If water temperature reads
wire disconnected or water greater than 0C, phone for
at 0C (freeze conditions). service.
F1 Thermostat reads greater Allow water to cool below 40C ,
than 45C. turn heater off then on again.
F2 Mechanical Hi Limit greater Allow water to cool below 30C,
than 45C. or 55C turn heater off then on again.
F3 Thermistor fault Phone for Service
F4 N/A
F5 N/A
F6 Flue temperature safety device Phone for Service
locked out due to over temperature
F7 Condensate drain blocked Phone for Service
F8 Heat exchanger sensor fault Phone for Service
F9 Heat exchanger sensor too hot Phone for Service
Greater than 240degC
L Heater locked out on time No action. Heater will
delay for 2 minutes. Automatically reset after
time delay.
time delay.
Pump operating & sufficient No action.
water pressure to operate heater
Thermostat calling for heat. No action.
Electronic Flame Supervision
operating.
Burner Operating No Action