overheat button

[neilwileman]

I wonder if anyone can help, i am an electrician and got called to a job this morning by a lady saying her boiler kept tripping out on the over heat cut out, on arrivel i discovered the boiler was mounted in a kitchen wall unit with harldy any room between the boiler front and the cupbaord doors. I opened the dooors and reset the cutout, and the boiler worked fine, i had it ruinning for 2 hours, the programer came on and of on required times so i couldnt find anything wrong. Could the boiler overheat due to the fact its in the unit?

 

[PlumbBobBob]

could be but not necessarily. some boilers are built to go in cupboards like this. someone more experienced than me will be along soon to probably better answer your questions.

 

[stevetheplumber]

unlikly stat measures water temp not air temp

 

[neilwileman]

What could cause it to trip out then?

I couldnt find anything wrong with the wiring, everything worked fine?

The kitchen has just been fitted so boiler wasnt in a kitchen wall unit before, The woman said it tripped out on friday, she opened doors and reset trip, went to work and left doors open, when she got home boiler was working as normal, so she shut doors, when she got up next day trip was off and no hot water. I did the same today, got there and trip was off, opened doors and reset trip had boiler runn constanty for over a hour, the set timer on programer to come on whilst i was there, and it did? I just want to eleiminate any possible wiring faults if any? as we moved programer from upstairs to kitchen and had to alter the wiring, but like i said it worked ok?

 

[stevetheplumber]

depends a lot on what boiler were talking about here some boilers in fact most now need a permenant live without this it could cause overheat due to no pump over run let us know the make and model for further advice

 

[neilwileman]

Not sure of the model, but it is a glow worm boiler, looked pretty old, its not a combi boiler either, its has a cover that u slide forword to gain access to the temp control knob and cutout button if thats any help?

 

[neilwileman]

Just found out the boiler is a Glow worm Ultimate, FF range

 

[BLOD]

If it's in a cupboard I'm sure this boiler needs high & low ventilation fitted

 

[neilwileman]

I've managed to download a instruction book, and it states that if the boiler is to be mounted in a cupboard of such like then a gap of 500mm minimum is required between front of boiler and cupboard doors!!

Maybe thats why its overheating?

i hope so

 

[kimbo]

I dont know anything about gas boilers but I have been doing oil boilers for 11 years and this also happens on oil boilers,It is usually either the control stat is letting the boiler to run on until it overheats or the overheat stat is coming on too early,If the problem has only just started happening and nothing has changed ie the boiler has always been in the cupboard and this has not happened before I would go for the stats,and they wont trip out all the time.

 

[mfgs]

I've managed to download a instruction book, and it states that if the boiler is to be mounted in a cupboard of such like then a gap of 500mm minimum is required between front of boiler and cupboard doors!!

Maybe thats why its overheating?

i hope so

It wont have anything to do with it being in a cupboard. As said before, the overheat stat measures water temp not the temp of the air around the boiler.

Dont mean to sound rude, but its not a job for an electrician. Its a job for a gas engineer. Best to pass it on to someone who is qualified to work on the appliance and has the required knowledge.

 

[Nat]

If its a room sealed appliance then the compartment it is in should have vents. 10cm squared per kw of the boiler high and low.

 

[GrahamM]

If its a room sealed appliance then the compartment it is in should have vents. 10cm squared per kw of the boiler high and low.

Think you are getting bit mixed up with combustion ventilation and cooling ventilation there Nat.
A room sealed appliance in a compartment only requires cooling vents if the Manufacturer specifies so. Most room sealed boiler fitted in recent years will not require cooling vents at all.

 

[Nat]

Think you are getting bit mixed up with combustion ventilation and cooling ventilation there Nat.
A room sealed appliance in a compartment only requires cooling vents if the Manufacturer specifies so. Most room sealed boiler fitted in recent years will not require cooling vents at all.

Hi graham.

No I wasn't confusing the two as if it is room.sealed then you obviously do not need combustion ventilation but you still need, unless, as you say the mi state otherwise, 10 cm squared of ventilation per kw for cooling.

I just checked my g1 book. Am I going mad here?!

 

[neilwileman]

Thanks all for your help, Just returned to the job this morning and boiler had tripped again!!I reset cut out and fired up boiler then went straight upstairs to look at the pump, It was red hot and didnt seem to be pumping at all, i altered the speed setting on the pump and it seemed to come to life!! Had it running for abour 30 mins then switched it off, pump ran on for about 5 mins then stopped, boiler trip stayed in. Could the pump be causing the boiler to over heat?

 

[BLOD]

yes if the pumps duff it will overheat

 

[stevetheplumber]

usually the 500mm measure ment is with the door open or removed to allow servicing not seen a boiler that needs that much clearance for cooling