Paul.. Help!!
Our combi boiler is really starting to get on my nerves now. The pressure of the water main in our area is quite low and if next door flushes the bog when I am running the tap, it reduces to a trickle, but I think that's besides the point... maybe.. The real concern is the hot water part of the boiler. I need to turn the tap on full blast for a minute or so to get the water hot. No problems there, but if I then try and turn the tap down a little so it isn't soaking me and the immediate vicinity, or start the hot water at a lower pressure rather than full blast, it goes stone cold within seconds. Then I have to turn it fully off and turn it on full blast again to get it hot. The top boiler (3 storey house - separate top boiler) doesn't have this problem, so I am guessing that there is some kind of water pressure sensor on the boiler to get the gas going? Is this adjustable so the gas comes on with less water pressure? If so, is it something I can tackle myself, or do I need specialist equipment? Any help appreciated.
PS: It has done this since it was installed. Could never get hold of the original turd who fitted it!!
Yours, increasingly annoyed,
Plumbing query for Mr. Barker
#1 Plumbing query for Mr. Barker
©2020 Lee
-
Paul Barker
- Social Sevices have been notified
- Posts: 8998
- Joined: Mon May 21, 2007 9:42 pm
#2
Whats the exact make and model?
-
Paul Barker
- Social Sevices have been notified
- Posts: 8998
- Joined: Mon May 21, 2007 9:42 pm
#4
I am having a problem downloading the MI's from Baxi group. I've asked them to send me a copy, could take time.
If it uses a diaphragm to sense water flow there are three likelyhoods.
1/ a piece of sand grit silt from flux solder debris from the water supply has lodged under the seat of the diaphragm
2/ the diaphragm is flawed, stretched or torn.
3/ the microswitch is faulty
A new diaphragm would be the first place to look, as even if it is silt, to do the job involves dismantling so might aswell renew it. Probably only a £5 part.
There is usually a metal gause filter on cold feed
which would want cleaning.
delta t is unhelpfully given as 6.5 ltrs / min at 50 degrees. The standard is to give the figure at 35 degrees rise.
I would expect your boiler to produce about 10 lpm at 35 dgree rise.
That translates to hold a measuring jug under hot tap to establish 10 ltre minute leave it running at that measure temp mains is about 7 degrees this time of year so you should get 41 degrees. If you do boiler is working fine.
Another possibility is that it is cutting out through overheating . A corgi registered person would check the max gas pressure is set properly.
If it uses a diaphragm to sense water flow there are three likelyhoods.
1/ a piece of sand grit silt from flux solder debris from the water supply has lodged under the seat of the diaphragm
2/ the diaphragm is flawed, stretched or torn.
3/ the microswitch is faulty
A new diaphragm would be the first place to look, as even if it is silt, to do the job involves dismantling so might aswell renew it. Probably only a £5 part.
There is usually a metal gause filter on cold feed
which would want cleaning.
delta t is unhelpfully given as 6.5 ltrs / min at 50 degrees. The standard is to give the figure at 35 degrees rise.
I would expect your boiler to produce about 10 lpm at 35 dgree rise.
That translates to hold a measuring jug under hot tap to establish 10 ltre minute leave it running at that measure temp mains is about 7 degrees this time of year so you should get 41 degrees. If you do boiler is working fine.
Another possibility is that it is cutting out through overheating . A corgi registered person would check the max gas pressure is set properly.