Fluctuating shower temperature, Potterton Gold

[Daljit]

Hi

I have a Potterton Gold combi, about 15 yrs old, and a thermostatic shower. When the shower is run, the boiler doesn't always ignite or if it does, it cuts out after 30-45 secs. I don't have this issue if i run a bath. In fact, i notice that if the shower runs cold and i switch on the HW bath tap, the boiler will fire up again.

I thought the problem was with the shower, so spent best part of 12 hrs yesterday ripping out a (very old) concealed shower, and replacing it with an exposed one just to find the problem was still there!

Any thoughts?

Cheers, Daljit

 

[Daljit]

From investigating further... i think the issue is with the DHW sensor, which i believe may also be known as a (magnetic) flow switch. It forms part of the hydraulic inlet assembly (about £100), which Baxi (i'm told) don't sell separately. However, found it on ebay for £15 so will see if that works.

 

[ianmcd]

blocked plate heat exchanger in the boiler

 

[durhamplumber]

From investigating further... i think the issue is with the DHW sensor, which i believe may also be known as a (magnetic) flow switch. It forms part of the hydraulic inlet assembly (about £100), which Baxi (i'm told) don't sell separately. However, found it on ebay for £15 so will see if that works.

Why buy cheap parts on ebay? You have no idea of their condition.If the part does not cure the problem how do you know it is not the part you have just fitted???

 

[Daljit]

Sorry, I should’ve said. It’s an eBay shop called boilerspares with 33,000 sales and a 99.8% positive approval rating. It only sells new parts.

Besides, it may not fix the fault. It might be smthg to do with the plate exchange, as someone above suggested. And a plumber I spoke to y’day, who’s fixing the part I ordered, said it might be to do with the turbine something or other. But he’s yet to actually inspect the boiler.

 

[Daljit]

Hi

just to post an update.

My heating engineer fitted the flow switch and it did the trick. Shower seems to be working fine now.