More flow needed to get hot water from combi boiler

[howiehilton]

Hi.

I have a Halstead combi boiler which has worked extremely well for the last few years, however it is now beginning to play up.
Over the last few weeks, I have had to turn the hot tap on more and more before the boiler will fire up and give hot water. It has been getting progressively worse, and now in the shower (a mixer) I get no hot water - I am guessing because the flow is restricted a bit more than a tap and because it is so far away from the boiler.

Could this be a diverter valve problem? How could I test it and if it is, am I legally able to replace it, or would a Corgi plumber have to come in.... we are trying to save some cash at the moment
thanks for all your help and suggestions
cheers Howie

 

[Strachan]

Ace or ace high?

 

[howiehilton]

its a quattro

 

[Strachan]

Sounds like a thermistor problem. You got a manual?

 

[howiehilton]

yes I have the installation and servicing instructions . I can see where the thermister is... looks easy to replace. Should I be testing the resistance of it to check if its faulty? thnaks Howie

 

[Strachan]

you`re the type of man we like on here! Get out the multimeter and give it a go. Have you the resistance settings in the literature?

 

[Agile]

I still think its the diverter!

Do you like the Castle Balti where you can take your own wine? Its one of my favourites!

Tony

 

[howiehilton]

I can't see them in the manual, but will have a scout round on the internet. Thanks for all your help... I appreciate the point in the right direction! cheers Howie

 

[Strachan]

Hope for his sake it isn`t. Ever done one? Only poked around in one of those monoliths, nightmare!

 

[howiehilton]

Tony - yeah, love Castle Balti - we went there 2 weekends ago. Excellent food and the naan breads are teh largest I have ever seen!
Howie

 

[howiehilton]

Hi again.
Is it possible to swap the CH and DHW thermistors to check their correct functioning? are they the same part? thanks

 

[Strachan]

I believe they are. Spares suppliers only list one type of thermistor for this boiler.

 

[ChrisR]

CHeck the diverter valve, the problem is quite likely to just be the diaphragm. See if the pin operating the switch on top goes smartly up all the way, when you open a tap to run about a couple of litres per minute. Bet it doesn't, and the CH flow pipe gets hot on HW call...

 

[Paul Barker]

If it's same dv as ace high the diaphragm is available seperately for £9 or if whole diverter required get the ariston Genus or eurocombi a27 mffi one, though you may have to swap a few bits off yours. The body is the same but cheaper, not studied them side by side so it may be that some of the interfaces are different, as they are between the two ariston models. All the diaphragms and glands should be right. Ariston parts are much cheaper. Don't buy the standard gianoni diaphragm it has a hole in the middle which is not very helpful when you don't have a rod to fill it.. Of course if it isn't the same hydraulics as the ace high ignore me.

 

[ChrisR]

If it's same dv as ace high

Er it isn't, Paul!!

It's ye olde giannoni one. There IS an ariston kit of bits to repair the diaphragm though which would fit, probably intended for a Eurocombi like an SX20 mffi.