Any Heating Engineers in ? poss boiler fault.
Any Heating Engineers in ? poss boiler fault.
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Discussion

Furyous

Original Poster:

25,237 posts

242 months

Monday 28th September 2009
quotequote all
We have a Protherm 80EC combi boiler.

For some time now, its been bugging me when using hot water.

Basically, turn the hot water tap on, boiler fires up, but hot water takes a few minutes to arrive at the tap, then the boiler switches off, even though the hot tap is still open, a few seconds later, boiler will re-ignite and the water temp rises back up to properly hot.

Is this as it should be ?

Plus, I cant actually run a bath, as even with the tap only partially open, the temp cycle is such that the batch is only ever half as hot it needed.

Any idea's before I try to call some one in to look at it ?

TIA.

cjs

11,408 posts

272 months

Tuesday 29th September 2009
quotequote all
Could be the diverter valve, a common fault on combi boilers. Does the central heating get hot when you run the bath? When you run the bath does the boiler run continuously or does it switch off and then kick back in?

dirkgently

2,160 posts

252 months

Tuesday 29th September 2009
quotequote all
Could be a blocked plate heat exchanger.

dickymint

28,179 posts

279 months

Tuesday 29th September 2009
quotequote all
does it not show a fault code on the display?

Mr Will

13,719 posts

227 months

Tuesday 29th September 2009
quotequote all
dirkgently said:
Could be a blocked plate heat exchanger.
We've just had exactly the same fault on our combi and this is what it was. Very common according to the engineer who came out.

Podie

46,647 posts

296 months

Tuesday 29th September 2009
quotequote all
Mr Will said:
dirkgently said:
Could be a blocked plate heat exchanger.
We've just had exactly the same fault on our combi and this is what it was. Very common according to the engineer who came out.
Yep, we had this about Jan time. The thin blades get blocked with hard water, then the boiler shuts off as it reaches the thermal cutoff point.

As someone else says, diverter valves are another major cause of fun (I await GregE240 to appear...)

Furyous

Original Poster:

25,237 posts

242 months

Tuesday 29th September 2009
quotequote all
cjs said:
Could be the diverter valve, a common fault on combi boilers. Does the central heating get hot when you run the bath? When you run the bath does the boiler run continuously or does it switch off and then kick back in?
Don't think the ch gets hot. Will check later, assume the boiler does not run constantly when runninn a bath.
No fault codes shown

dirkgently

2,160 posts

252 months

Tuesday 29th September 2009
quotequote all
dirkgently said:
Could be a blocked plate heat exchanger.
Part No 0020043598
Parts centre No 441088
£76.40 + vat

smac

164 posts

256 months

Tuesday 29th September 2009
quotequote all
Could be the hot water thermister. Cheap fix if it is