Boiler not supplying hot water to upstairs

26 May 2012
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United Kingdom
Good afternoon, I'm hoping for some advice,

Our Combi boiler has an issue where it will switch on and provide hot water to downstairs (Bathroom & Kitchen) but will not for upstairs (Shower and Sinks).

The only way to get hot water upstairs currently is to put thermostat up 1/2 a degree and trigger heating to come on, we then get hot water during that period,

The boiler is approx 8 years old so not sure if its a big issue or a simple fix,

Any help much welcomed and appreciated!
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Some use flow switches to detect that HW has been demanded some use diaphragms, if it is 8 years old and the Diaphragm hasn't been changed that is your most likely culprit, tell us which model you have or post a pic of the boiler and we will tell you which system it uses
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Hi Ian just asked someone to check - Baxi Potterton Main Combi 30 HE ?
That boiler is Diaphragm operated and that would be my first place to check, if it is torn or just has samall tear that is why there isnt enough flow in the upstairs taps to operate it, there can be other things like the water venturi partially blocked but my firs check would be the Diaphragm, not expensive and easy to do, if you are going to do it yourself, make sure you cover the PCB housing with some kind of Polythene, cling film or polly bag and a good sized towel, they are terrible models for water getting into the PCB when you are doing that job
Thanks Ian you have been very helpful, don't think I would have the confidence to take that on myself if it is that what would you think an engineer would charge?
The diaphragms are not expensive and a van stock item for a lot of us so usually an hours labour but every one is different and all have different rates, so cant really give you a price

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