Truma Water Heater - intermittant problem

[Deleted member 207]

I've got a 20 year old Truma 14litre gas water heater, that works for weeks fine, then wont fire up at all for a few days, then will fire up again. I wish it would just stop working then its easy to troubleshoot.

My usual start up routine is turn switch to 40C, wait for the thing to fire up and the igniter to stop clicking, then turn up the temp to whatever I want. When the thing wont fire, the gas lights ( I can hear the flame and smell the fumes from the exhaust), after about 15 seconds it clicks off and the red light comes on.

I've done the usual things - given the circuit board a squirt of silicon, hair dryer onto the electric connections, had a rummage around to make sure there is not a water leak.

Any thoughts from the Oracles?

 

[simong]

would it have a gas shut off valve, the type that if it doesn't light or get blown out it turns off the supply? if so it may be a fault with it

 

[Deleted member 5759]

Make sure the thermocouple is sitting in the pilot flame correctly.

Peter

 

[Channa]

Make sure the thermocouple is sitting in the pilot flame correctly.

Peter

or not knackered!!!..

if the thermocouple is defunct , by nature of its job ..your gas will extinguish itself...also thermocouplings need a few seconds of action so that the yunderstand you want the appliance on

Channa

 

[scotsy]

My gas fire at home (open with charcoals) started gradually failing to light or even just 'go out' when lit. I changed the thermocouple and it was the same but after further investigation it turned out to be a partially blocked jet in the pilot light feed that made the pilot smaller and weaker and not flaming properly on the tip of the thermocouple. The thermocouple was shutting down the gas valve (as it should do). It may be something similar but i've no idea how you would be able to check or fix this on a motorhome? maybe one for the gas engineers i'm afraid (or a new boiler?)

HTH
Ian