Overheating Boiler?

[Ken Weller]

Our boiler has 2 temp settings "High" and "Low". We used to use it on High and sometimes got banging from the boiler, then it would be okay for months. The pilot light died recently and the plumber replaced the thermocouple and an overheating sensor. The boiler will now only run on low and takes hours to heat the house if at all! When run on High it shuts off after about 5 mins. Also shutting of the pilot light. I need to run it on high.
I guess the overheating sensor is now doing its job. At least as a temp measure I need a way to reduce/remove its effectiveness.

Is it 230v or LV? Does it detect just temp or vibration (banging) as well? Might I have an oversensitive sensor? When it gets too hot does it go open circuit or closed circuit? Could I stand it off the boiler a little or simply have it loose in the casing?

Would this be a reasonably safe thing to do?

Thanks - The wives and kids are freezing!

 

[gas_man_gaz]

ya cant tamper with the overheat stat in any way, its a saftey device.. id get a corgi lad out to check ya boiler out.. if its the boiler iam thinkin of i think it has 2thermisters (1for the high and 1 for the low setting) - what boiler is it?

 

[twgas]

is this an 'apollo' if so sounds like your pump is shot which will cause the overheating, banging and all round poor performance

 

[bengasman]

Pump or blockage, limescale, corrosion, open vents are prone to it

 

[Agile]

Yes, its an Apollo!

Unless the pump and circuit are in very good order few of these will run on the high temp setting.

This poster is potentially dangerous as he has no understanding of boilers and yet wants to tamper with safety devices.

Tony