Luke warm water from Halstead Ace boiler.

[jupiter_1963]

Hi,
My Halstead Ace combi boiler will not fire up for DHW unless the the tap is opened fully. I then only get luke warm water. To get piping hot water I then have to reduce the flow from the tap to about 30% of the full flow. If the central heating has fired up then DHW will not fire up at all.
The central heating works fine.
Does any one have any ideas?

 

[ChrisR]

Do a search on Diaphragm.

 

[jupiter_1963]

Thanks for the advice.
They do a diverter valve diaphragm and a diverter valve inner service kit.

Which one do I need? Or do I need both?

 

[jupiter_1963]

Well I,ve been fiddling with this boiler for the last couple of days now. Still no hot water.
If I take the DHW switch off and operate the switch manually the boiler will fire up straight away. The pin that should operate it comes out, but not far enough to operate the switch untill the water is at full flow.

I have pulled the pin out manually but still get no hot water, though some of the pipes are hot.

The housing that holds the pin in place needs a rather large spanner, maybe 30mm, which I havn't got. I don,t want to buy one if I don't need to.
Any advice or info would be greatly appreciated.

 

[ChrisR]

Still consistent with just the diaphragm being holed.
Manual's on their website.
Diaph's on the right, no need for a big spanner.

 

[jupiter_1963]

Wasn,t sure which diaphragm I should be looking at.
Pulled out the large diaphragm to the right and sure enough theres a hole in it!
Now I just need to get a replacement.

One guy quouted £39 +vat!!

Halstead quoted £26.38.

Seems alot of money for a rubber disc, or are the maybe quoting me for something else?

 

[jupiter_1963]

Thanks for pointing me in the right direction.
Took the old diaphragm to the merchant who quoted £26 for a halstead one and asked if he could match it with a cheaper one.
Came away with an identical one for £8.
Got hot water now. Thanks.