Boiler Problems

[Marty]

Ive had this problem for a good while now, but seeing as i've not needed my central heating through the summer i've not got around to fixing it (yes im lazy;)).

 

Basically, i've got a combi boiler. It works fine on the hot water side of things, but not on the central heating side.

If i put the heating on, it will fire up, heat the radiators etc up ok, but it will always go out within 30mins of being turned on. It goes completely out, inc pilot light.

But, i could leave the hot water running all night and it wont go out. So its not the thermocouple.

Anyone got any ideas?

Its starting to get a bit of a nip in the air now so i can see me using the central heating soon

[johnnyknox]

Sounds a little bit like what I had:

 

http://www.mkivsupra.net/vbb/showthread.php?t=124463

[RIJ8631]

Marty, quote make and model, and it might gives us and idea.

1) Do you have TRV's (thermostatic rad valves) on the radiators, if so what are they set at ?

2) Is the pressure OK on the pressure gauge - should be approx 1 to 1.5 bars ?

3/ Some permanent pilot boilers have an overheat limit stat fitted ( aka interupter). Could be that its getting "weak".

 

Come back with some answers and we'll see what we can suggest

cheers

Ian

[snake]

it could be the diverter valve if its a worcester boiler, had a similar problem .when you try to put the heating on for instance it wont work but the hot from the tap will .

[Marty]

Sounds a little bit like what I had:

 

http://www.mkivsupra.net/vbb/showthread.php?t=124463

Similar matey. Although my pilot light has been on for the last 5months it only went off after 30mins of having the central heating on

 

Hope it doesnt turn out to be expensive

 

Marty, quote make and model, and it might gives us and idea.

1) Do you have TRV's (thermostatic rad valves) on the radiators, if so what are they set at ?

2) Is the pressure OK on the pressure gauge - should be approx 1 to 1.5 bars ?

3/ Some permanent pilot boilers have an overheat limit stat fitted ( aka interupter). Could be that its getting "weak".

Come back with some answers and we'll see what we can suggest

cheers

Ian

 

Its a worchester 240 boiler,

1- i have no thermostatic valves no, just normal ones

2- the pressure is 1.2bar

3- Sounds like it may be something like this? but wouldn't this operate on the hot water side too? which it never goes off on, weird?

 

 

it could be the diverter valve if its a worcester boiler, had a similar problem .when you try to put the heating on for instance it wont work but the hot from the tap will .

It is a worchester boiler mate, but the heating does actually work, the radiators get red hot, they just dont stay that way

[kieren1234]

I get 25% discount on CHC (central Heating Care) at Powergen (where i work), if that could help in the future.

[ozz]

I ad a similar problem in the past, was the fan not working. Spray it with a releaser and it was fine for months.

 

I too posted on a forum and was warned that its not the sort of thing you want to mess around with and you should get an engineer out.

[JohnA]

I've had a similar problem (also Worchester Bosch) and a very helpful member here talked me into fixing it.

In my case I had to repressurise the vessel.

Sounds complicated, but it's just an airtank with a bicycle valve on it, that needs to be at 1bar when cold. This has a diaphragm inside that regulates the pressure when hot.

Does your water pressure go up and up and up during CH operation?

[RIJ8631]

[quote=Marty;

 

It is a worchester boiler mate, but the heating does actually work, the radiators get red hot, they just dont stay that way

 

It could be cutting out the pilot on the overheat limit stat. The radiators should not really be "red hot " - combi's have safety stats built in which detect the boiler getting too hot and cut out the pilot.

Turn down the central heating control on the boiler and see if the heating works ok then. Set the control to give a temperature of 50-60 degrees ( if a temperature gauge is fitted ). Might just be that you are running the c/h at maximum settings which is too hot for the boiler.

cheers

ian