worcester boiler probs

[jerry1964]

Hi all, I have a worcester bosch 280rsf boiler I am having probs with. It apparently keeps over heating and the over temperature switch keeps popping out and requires re-setting.
Any suggestions?????

 

[zimmers]

pressure is it ok 1bar - 2 bar,if so your pump might be going and sludge may be causing poor circulataion is your h/w ok or is it both ?

 

[jerry1964]

The pressure is ok.It trips out on both the heating and hot water.The boiler runs for 10-15mins before it trips out

 

[zimmers]

Jerry,it could be a build of sludge in the system, which has caused the heat exchanger to stop the water flowing through as it should and its building temp right up and as the sludge has nowere to go its getting very hot and the o/h stat is coming in.The worscter 240 was really well known for its secondry heat ex to block up and cause o/heating proplems.how old is the boiler and is the rads older or same age

 

[clf-gas]

280 rsf is the combi Zimmer, would put money on scaled up HE, with a side bet on the driver board.

 

[jerry1964]

Jerry,it could be a build of sludge in the system, which has caused the heat exchanger to stop the water flowing through as it should and its building temp right up and as the sludge has nowere to go its getting very hot and the o/h stat is coming in.The worscter 240 was really well known for its secondry heat ex to block up and cause o/heating proplems.how old is the boiler and is the rads older or same age

Zimmers,The boiler is ten years old.The rads are about the same age.

 

[clf-gas]

Jerry youin a reasonably hard water area so would think your he is scaled up.

 

[ChrisR]

It trips out on both the heating and hot water.

Nowt to do with hard water then.
I'm with Zimmers, on this one.
Pump - when the ch comes on, does the heat get round the rads?

 

[zimmers]

gerry i honestly think its your secondry heat ex the white roundish part with 2 pipes either end.its blocked up now what id do is get it changed ,ive tried to powerflush them clear but no good ,you can try putting some chemicals in and leaving for a while,but its classic signs of this being sludged up

 

[jerry1964]

gerry i honestly think its your secondry heat ex the white roundish part with 2 pipes either end.its blocked up now what id do is get it changed ,ive tried to powerflush them clear but no good ,you can try putting some chemicals in and leaving for a while,but its classic signs of this being sludged up

Zimmers,

I've tried the heating this morning.It's been off all night and is stone cold.If I turn the mains switch on the fan runs for a few seconds and then cuts out.The o/h switch has been reset.This stays down.After the fan cuts out there is a constant click as if a switch is switching in and out for about 20 seconds then this stops as well.All seems a bit weird to me.......

 

[jerry1964]

It trips out on both the heating and hot water.

Nowt to do with hard water then.
I'm with Zimmers, on this one.
Pump - when the ch comes on, does the heat get round the rads?

Chris,The heat gets round the rads no problem.I Think that the pump is ok.

 

[Stingray13]

Should really check the stat first it could be faulty could be to sensitive, as this is what's happening before we look at what could be causing it should make sure the stat isn't faulty.