Modena 80E Boiler - Can't stop heating!

[eastender3]

Hello All,

This is a great site, have to say.

I have a 7 year old Modena boiler, recently, not sure if the Mrs fiddled with the timer or not, the heating seems to start, even when the temp knob is set to summer, as a minimum.

Not sure what the problem is, could it be the Temp sensor that needs adjusting or replacing, if so what the likely cost to the part. Or is the timer switch that needs to be looked at?

Called an engineer and he thinks it's timer switch, but in the past we never botherd with timer, we set the temp knob to min, that was it, we had water only.

 

[gaspro1981]

does the radiator neon come on the front of the facia even if the timer is off and the selector switch in hot water only mode

 

[namsag]

combi ??? ...... hot water microswitch sticking or pin not retracting after use

 

[Gasguru]

Uses a flow turbine so can't stick on.

First thing is to disconnect the timer and see if heating still on...the relays inside often stick on. Also check the heating temperature knob spindle hasn't sheared off. Otherwise time to call someone in.

 

[eastender3]

does the radiator neon come on the front of the facia even if the timer is off and the selector switch in hot water only mode

Yes, the radiator lights comes on and the burner ignites, even when the timer is off, when the selector is hot water only.

 

[eastender3]

combi ??? ...... hot water microswitch sticking or pin not retracting after use

Yes, it's a combi boiler. If it's either of these, are they expensive to repair?

 

[kevindgas]

99.9% of the time it is the timer they are not that reliable.
easily replaced just 2 some have 4 screws and 4 wires live neutral and two blacks (the switch wires they fit either way round)

2 screws hold the main cover underneath
2 screws hold the control panel
and 3 screws hold the pcb cover on

try not to mix up the screws!!