Worcester Bosch 280 rsf Overheat thermostat By-passed??

[sonnyd14a1]

Hi all, previously posted about my room stat which is still an issue but taking a closer look at the wiring diagrams my overheat thermostat has been by passed, is this leagal? obviously this is a safety issue and should of been picked up when serviced??

I still cannot get my timer unit to control the on off function for my heating, the red indicator switchs off on the correct time but the heating actualy stays on is only operated by my optional room thermostat!

Thank You

 

[sonnyd14a1]

Just tested and there is no resistence through the Overheat Thermostat.. Looks like it was a quick fix bodge by an engineer??

 

[ianmcd]

there shouldnt be any resistance it is an open and close thermostat, do you mean that it is showing open circuit ?

 

[sonnyd14a1]

Yes it is open circuit, doing abit of research on why there maybe issues with the Overheating Stat (which is currently by-passed) and with this boiler it shows signs that the water to water heat exchanger maybe scaled up? My hot water is luke warm and not hot at all, runs around 20 degrees cent.

thank you

 

[Gasguru]

It should not have been bypassed. Can you reset it by pushing down the button?

 

[ianmcd]

as above it should never have been by passed you should not be using the boiler with this by passed it is a safety device and there to protect your boiler

 

[sonnyd14a1]

I have just pushed it down, there was no click, it was a smooth slide down when pressing the button, I now have around 3ohms present..

 

[sonnyd14a1]

as above it should never have been by passed you should not be using the boiler with this by passed it is a safety device and there to protect your boiler

We brought the house and 3 months ago and the room stat went, old danfoss manual stat, so i replaced with a drayton rst1 electronic room stat and the heating will not shut off from its integrated timer.. also the hot water is only luke warm.. and the upstairs rads only get warm altho downstairs are hot but down stairs is 15mm pipework and upstairs is 8mm..

Such a good boiler but i think this one is gonna have some money spent on it

 

[ianmcd]

I dont think you have a problem with your boiler more with your system, connect the OH stat back up and remove the by pass piece of wire, dont by pass it again if it operates

 

[sonnyd14a1]

I dont think you have a problem with your boiler more with your system, connect the OH stat back up and remove the by pass piece of wire, dont by pass it again if it operates

So whats the next steps if it goes open circuit again?

Im a white goods engineer by trade but obviously never touched boilers so have no experience on what can cause what. I can assure you I will not bypass the overheating thermostat, like you said Its a safety device..

 

[ianmcd]

if it goes open circuit again you need to find out why the heat is not getting away from the boiler as already said I think it is a system problem not a boiler problem

 

[sonnyd14a1]

System you mean by pipework and radiator flow??

 

[ianmcd]

yes and or any external controls valves by-pass etc, for some reason the heat cant get away from your boiler fast enough and the OH stat is just doing what it is designed to do

 

[Agile]

It may well be tripping below the rated temperature.

3 ohms is rather high.

But the normal solution would be to replace it.

I dont think it was bypassed by an engineer. Probably a cowboy or DIYer!

Tony

 

[sonnyd14a1]

It certainly does not look like a new one so it may pay to replace.. Do I need a gas safe engineer to fit this then? I pressure it does into the combustion unit?

Oh and Ive sorted the heating bein on all the time, looks like a sticky relay on the integrated timer unit, few taps and its released and is now shutting the boiler off at correct times.