CH okay, hot water rare

[pvcelt]

Hiya.

No problem with the central heating, but over the past few weeks the hot water has been coming through cold sometimes when I run it. If left for ten minutes and tried again it was coming through, but that is working less and less now. Running it with the heating on no longer helps. No problem with flow of water , just the combi boiler is not heating it. It's a Saunier Duvall 30E, which was here when I moved in three years ago.

Be grateful for any advice on:
-What's wrong?
-Could I have a go at sorting myself(basic DIYer)?
-If not, how much would I expect to pay a pro?

Many thank in advance,

Kevin

 

[mickyg]

does the boiler actually fire when you open the tap?

 

[holty]

might be worth checking the connections on the flow switch and thermistor. this boilers a nightmare for loose connections.then id go down the route of testing flow switch or ntc.love SD /GW advice on testing a flow switch.basically they sugest buy a replacement take the wiring harness of the old one and put on new then blow into it simulating fLow.sure the guy in the shop is gonna love it when you ask for a refund cause that aint the fault.

 

[pvcelt]

The boiler doesn't fire up, Micky. Except of course the odd occasions it is actually heating the water.

 

[mickyg]

sounds like its not recognising the demand then. Could be the flow switch as mentioned. Prob first port of call, most other faults would result in a fault indication.

 

[pvcelt]

Thanks guys, will look at the flow switch when I get home.

 

[DP]

It is best to diagnose the fault with aid of boiler manual. Unless you are familiar with the boiler and have a test meter, I think you will be better to get someone in. Not just anyone but some one who repairs boilers for a living instead of just fitting them.

 

[pvcelt]

Yeah, had a look at the manual last night and decided it was beyond me. Will try to get someone in. DP, are you such an engineer in Glasgow? Please PM me if you would be interested.

Thanks for all the advice.

Cheers,

Kevin

 

[Agile]

Holty, I dont see any other way to see if the flow sensor is failed other than that substitution method!

I think that I am missing something but I dont see how to send kevin a message.

Forum users can contact me from my profile where I have all the contact information.

Kevin you can look up Danny ( DP ) in your local listing as ranoch services.

If that Sonya Duval is the same as the G-W 30si then a sticking flow switch is a very common fault. I have never had to replace one and just open it and wash it out. I never see any dirt but it always works afterwards ( for a while at least! )

Tony