noisy potterton combi 80

[martinmck]

I have a combi 80 boiler. Everything was going fine until other day. Ran hot tap upstairs for 5-10 mins. Switched off tap, then almighty babnging coming from boiler, which cut itself out. I released steam from top of boiler by turning plastic screw. Noise now happens everytime hotwater tap is switched off after a shower.

would any kind person have a few clues as to what the cause maybe?

I get the impression that the boiler is still heating water after the taps have been switched off. Green light indicating gas flow.Water is boiling and then load banging then cutout.

 

[kevplumb]

flow switch

diverter valve

 

[martinmck]

thanks Kev

elow switch or Diverter valve, ok will consider your advise. Is it still possible to get imformation for these boilers with respect to drawings, so that i can locate the Switch and valve you suggest?

 

[bradleybear]

The DHW microswitch is sticking
After you turn the tap off, the boiler still fires for Hot Water, with all that heat going nowhere, its no surprise your boilers rocking n rolling.
Very common fault as on the Potterton Puma.

1)Clean and lubricate DHW switch, or replace if still plays up
2) Might be necesarry to change DHW flow valve, sometimes leak and covers DHW switch in green/brown cack.
Complete part unfortunately, about £45 for the valve, and £4 for the switch, plus labour charges from a Corgi registered heating engineer.

 

[Slugbabydotcom]

elow switch

Was a typo, he meant flow switch

 

[kevplumb]

try here

 

[doitall]

or if you want the proper copy send me an email

 

[kevplumb]

ahhh isnt he lovely

 

[doitall]

ahhh isnt he lovely

Hands off marra, I'm saving myself for Chuck

 

[kevplumb]

 

[martinmck]

thanks for your replies, first time using this site, and hey, what a result. I feel suddenly surrounded by peeps with solutions, great.

there is indeed "green/brown cack" (are you in the boiler ?) Thanks Bradleybear, now I at least understand a little more, will have faith to get in corgi registered guy( If i can find one here in Torbay).

is it possible to see drawings to confirm position of the switch, suppose I should ask potterton in Preston.

thanks again

Mart

 

[kevplumb]

follow the link

 

[bradleybear]

Switch is behind the PCB's on the end of the brass flow switch. Has two wires, (orange if I remember rightly), and screws into the flow switch, with a locknut on it.

 

[gazthepottertonengineer]

potterton are in Warwick

 

[gazthepottertonengineer]

make sure lock nut is in correct position or wont make switch when tap is turned on