Our Combi boiler isn't giving any hot water, although the central heating comes on fine. I have noticed the pressure guage goes between 2-3, which I know is too high. I have checked the controls for setting the timer etc., to see if I'd 'caught ' one by mistake. I would be grateful for any help with this.

Carolyn Perry, May 2007

hi all dose halstead ace boiler have a rubber diapram or meatal boiler part number is 840505 many thaks

andy, October 2012

fixed my boiler this morning, halstead ace, symptoms were as above, got the diaphramme for 6quid ebay, followed instructions from marks comments, follow marks advice and you want go wrong, everything works fine, i must say ive had my halstead for about 8 years with no servicing and no problems! thanks and good luck

peter may, August 2012

A big thank you to Paul, changed diaphragm in no time Hot Water restored and my bank balance. The engineer said it could not possibly have been a Diaphragm!!

Thank you one again, genius...!

Mike E, March 2011

I meant Gas Safety (installation & use) Regarding 1998

Lewis, January 2011

Please be warned that you must be Gas Safe registered to carry out any work in relation to a gas appliance. Under the Had Safety (Installation & Use) Regulations 1998, Regulation 26/9 (a,b,c,d) states you must ensure the boiler is working correctly and safely and to do this you need to check gas pressures and analyse the glue gases for correct co/co2 ratio. Unless you are Gas Safe Registered you can't legally do this and by working on any gas appliance you are putting yourself and others at harm.

Lewis, January 2011

Hello Paul,
i have tried to change the diaphragm by following your instructions but i am stuck at the following step.
6. Unscrew the flat L-shaped plate at the left-end of these 2 pipes
7. Pop out the 2 silver pipes (some water will spill out but not much) - mind the o-rings at both ends of both pipes - if these bust you should be able to get new washers at any B&Q etc
my questions is thet does these 2 pipes pop out either from left or right side , bcz i tried to pull these out from left side but these pipes were not commin out so that why i didnt pull very hard as i was afraid of damiging these pipe.
please assist so i can take these pipe out to change the diaphragm.
thank you and i will wait for your reply.

Tanny, December 2010

our boiler will not go on but when the reset button on the front panel next to the green lit burner is pressed comes on for 7 seconds the goes off, has any one else had this problem? Also where is the ignition button at the back of the boiler as I cannot find it.

Thanks

Jane on a frosty night.

jane, January 2010

new diaphram needed more than likely distorded or split .cost u 6 pounds hrps

tomo, September 2009

Our Boiler pump etc seems to be working fine but we are having to tap the underside of the boiler housing were the circuit board is to get the boiler to fire up. Do i need a new circuit board.?

Mark, September 2008

I've just had exactly the same problem and just sorted it. Here's how.

Symptoms:
Heating comes on fine but hot water (e.g. for shower) does not. Problem starts out being kinda intermittent but then starts happening all the time. Initially can be solved by turning on the central heating to get hot water for the shower but eventually even that no longer works.

Problem:
Tear in the hot water diaphragm. An intact diaphragm will tell the boiler when a tap has been turned on as the pressure on one side will be different to the other side. A tear in the diaphragm means no pressure differential so the boiler does not fire up when a hot water tap is turned on.

Solution:
1. Get a new hot water diaphragm for a Halstead Finest Gold Combi Boiler (gas council # 840-505). Cost approx £30 from somewhere like Gasworld in Acton.
2. Drain the boiler, turn off the mains water & electricity to the boiler
3. Remove the top panel (screw on the top surface) and be ready to unscrew the panels on the bottom surface so you can get access as needed
4. Take pictures of the boiler so you can remember what it looks like when you're disassembled the following pieces
5. See the 2 parallel silver pipes with some 90 degree bends in them going left to right across the bottom of the plumbing at the bottom - cut the ties on the right hand side of them where they go into a disc-shaped brass object which is side-on to you & pull the pins out, probably breaking a red wax seal
6. Unscrew the flat L-shaped plate at the left-end of these 2 pipes
7. Pop out the 2 silver pipes (some water will spill out but not much) - mind the o-rings at both ends of both pipes - if these bust you should be able to get new washers at any B&Q etc
8. Unscrew the 2 (vertical) brass screws which are holding this brass disc in place and just pull it off the left hand end of the spindle
9. Unscrew the approx 6 or 8 screws around the outside of this brass disc, lessening the pressure around the perimeter gradually and lever the 2 parts of the disc apart
10. You'll see the 2-part diaphragm inside which should look exactly like the replacement part you bought earlier - there's probably a small tear somewhere on the black rubber diaphragm
11. Replace the diaphragm & re-assemble, making sure you pop the silver pipes in as far as you can else you'll have some water squirt out when you turn the mains water back on
12. Be careful of the water pressure gauge - I busted mine at some stage during this process - I think the wire/tube at the back of it is fragile
13. Send me a cheque in thanks for saving you £75+VAT+£30 parts!!

Paul S, April 2008

When I had this problem I was told I needed a new diverter valve - as the name suggests it diverts the hot water from the central heating system to the tap. A diverter valve costs about £50 to buy. I was too nervous to try fitting this myself so I telephoned Halstead and they gave me the name of an engineer they recommended in my area.

Helen Cherry, May 2007

Hot water is independent of the timer on your boiler. Probably the diaphragm in the diverter valve. These can be repaired with a service kit although not all engineers are happy doing this.
It's not particularly hard on the quattro gold but there are one or two things that can go wrong if you are not familiar with draining and filling your boiler.
If you aren't confident about it, ring round your local corgi engineers and ask for estimates.
Depending on where you live a repaired valve £70_£100,
A new one probably £150-£200.
Don't quote me on that, it varies a lot.
Good luck.

T.h.s, May 2007