Oil Boiler Stat Thermostat / overheat source replacement advice needed

[Hollie Bedford]

Hi!

Following some ongoing problems my Boiler Thermostat has completely stopped working rendering my heating non existent! The overheat reset button is now not working at all.
I also believe that the actual thermostat function has stopped working properly - for some time have been having problems with kettling/boiling from return pipe in F&E tank. And even when stat turned right down heating was very hot.

I need a replacement but cannot seem to track down correct part - all the ones that seem to look correct to me are listed as ‘cylinder thermostats’ example below

https://www.screwfix.com/p/strom-ss...MI8_bh6vXv5gIVCLrtCh1sswjXEAQYASABEgKpSvD_BwE


The boiler is (ancient) Trianco-Stewart TSO B)23/29

The existing thermostat is satchwell sunvic TKD 263/3

If anyone can help with directing me to correct part would really help.
Since both the boiler and stat are so old I cannot seem to find any info/specs online.

Otherwise I could turn off electricity to boiler and remove the stat to take to a local heating/plumbing store.

 

[CBW]

Good evening,


The last photo posted looks like a cylinder thermostat to me, and set at 80 degrees will be hot. Also if overheat won’t reset, nothing I doubt will work.

 

[Hollie Bedford]

Thanks. Will buy the one that I think looks similar and go from there. Actually it’s not set on 80 that knob has actually fallen off ages ago and been adjusting from inside. Just put the cover on to show how it looked. Normally set around 60 odd I think.

 

[Hollie Bedford]

Inside of thermostat.

 

[ianmcd]

Otherwise I could turn off electricity to boiler and remove the stat to take to a local heating/plumbing store.

Absolutely no point in doing that, Call satchwell and ask if they have an equivalent part number, this one might fit

https://www.ebay.co.uk/itm/Satchwel...033440?hash=item364dd4eb20:g:SNYAAOSw4W9c49By

 

[oilhead]

Your last picture shows a TKD3501. If no longer available, there are IMIT thermostats used on Warmflow boilers, or there is a dual stat marked as Firebird. You need a dedicated boiler spares stockist. Try www.abgo.co.uk or www.hwos.co.uk .