Ideal Classic FF270

[f1005705]

Hi There,

I'm looking for the part numbers for a limit stat and an overheat stat for the above boiler.

I guess the LXff uses the same stats?

Can anybody help please

Thanks

Tony

 

[shambolic]

need to let me know what stats
Is it the resetable stat at the bottom!?

 

[f1005705]

need to let me know what stats
Is it the resetable stat at the bottom!?

Well where do I start.... my boiler is kettleing but only when heating the hot water and then only when it's heated it in the morning no hot water has been drawn then it comes on in the afternoon (on timer). it seems not the shut off.

I have changed the stat on the tank and made sure it works by turning it down while heating. The problem seems to be that the boiler does not shut down when the water heated by the boiler in the tank coil is hot enough to heat the water in the tank (don't know what that is say 90oC).

I assumed that the limit stat would control the on off of the boiler (fire up/down) when the heat is sufficent to heat the water .

So i gess it would be the one on the PCB red reset one.

Any other ideas would be great.

 

[shambolic]

There are several different versions of the classic but the red overheat stat is a resetable one so would turn off the boiler altogether There is a limit stat on the flow as well.
But depending on model it is a thermister in a dry pocket linked to apotentiometer that controls the heat leaving the boiler.
I personally would take a flow and return temp reading at the boiler to check my diffs and also the flow temp 82 at number 6 on the dial.
If yer diff temps are too high then its a circulation problem.
It could also be a mv problem with the end switches staying closed sending power to pump and boiler without demand from room stat.
There are several avenues to check first, try these 2 first.

 

[shambolic]

Cyl stat should be set to approx 50-55. deg

When the tank reaches this temp it should shut zone valve turning off pump and boiler.

 

[f1005705]

Thanks for the pointers so far.

The tank stat is working ok and does shut down the zone valve, pump and boiler when temp is reached.

I tried replicating the fault last night and put the hot water on constant for 2 hours and it seemed to work as I would expect i.e zone valve opens, pump comes on, boiler fires heats the water in the coil when coil water reaches temp boiler shuts down and pump continues to run until coil water temp drops and the fires up again until the tank has reached 55c then it does as it should and suts down until water in tank drops below 55c.

So I think I have an intermittent problem which seems to point to the water circulating the coil is overheating and then kettling. Would this point to a 'flow' stat problem or one of the other issues mentioned?

I don't help that it's intermittent

Thanks again

Tony