When connected to tap my water hose is blowing off after a couple of hours and hot water pours out( heater on electics). No Leakage internally and it doesn't happen on internal water or when the heater is on gas. Any ideas anyone?
twobob said
09:10 PM May 25, 2009
Gary, not wishing to state the blooming obvious, its a pressure build up, as you will know, but why?
I will have a crack at an answer, and see if that helps
All HWS have a safety relief valve, to prevent over pressure from the heated water. This is normally set higher than mains pressure. I do not think it is this, but maybe check it operates.
When on tank water, any over pressure will be returned to the tank, so you would not notice this.
If I am right, on gas, the system heats to a certain point, but only cuts in to full, when in use, ie water flow, so again, you would not notice the problem.
So my conclusion is that on electric, it heats to full temp, and the pressure, while below the relief valve setting, is greater than the abilities of your fittings.
The answer may be a check (backflow) valve on the van, but only if the releif valve functions correctly.
Maybe someone with better knowledge has an answer
Gary and Kerry said
07:51 AM May 26, 2009
twobob wrote:
Gary, not wishing to state the blooming obvious, its a pressure build up, as you will know, but why?
I will have a crack at an answer, and see if that helps
All HWS have a safety relief valve, to prevent over pressure from the heated water. This is normally set higher than mains pressure. I do not think it is this, but maybe check it operates.
When on tank water, any over pressure will be returned to the tank, so you would not notice this.
If I am right, on gas, the system heats to a certain point, but only cuts in to full, when in use, ie water flow, so again, you would not notice the problem.
So my conclusion is that on electric, it heats to full temp, and the pressure, while below the relief valve setting, is greater than the abilities of your fittings.
The answer may be a check (backflow) valve on the van, but only if the releif valve functions correctly.
Maybe someone with better knowledge has an answer
Thanks Bob, I have had a closer look this morning , there is a one way valve between the HWS plumbing and the fill point and so i think this is probably be the culprit. Will only turn HWS on just before use whilst connected to mains if i can't get a replacement before getting home. We don't spend a lot of time in CP's so shouldn't be a major issue.
Cruising Granny said
05:54 PM May 26, 2009
I have found if I only turn the main supply tap on about half flow and not flat out it doesn't blow off the connections.
Also make sure your connections are all firm. Brass has a longer life.
It's a bit of trial and error. Good luck with that. Cheers Chris
Basil Faulty said
05:22 PM May 30, 2009
Has to be the non return valve..... Have you tried cold showers? Have you checked the anode?
troublemaker said
12:37 PM May 31, 2009
Ok most units have a relief valve that should drip some water as it heats up to relieve excessive pressure... .....make sure this is working by observing that water drops from the relief pipe.
But. . . .. your problem is the check valve in the piping
It wont be the anode. . ..that is only there to stop corrosion and rust.
Basil Faulty said
08:19 PM Jun 3, 2009
troublemaker wrote:
Ok most units have a relief valve that should drip some water as it heats up to relieve excessive pressure... .....make sure this is working by observing that water drops from the relief pipe. But. . . .. your problem is the check valve in the piping
It wont be the anode. . ..that is only there to stop corrosion and rust.
Yes I meant have you checked the anode to make sure you still have some anode left, they get used up quickly.
Any ideas anyone?
I will have a crack at an answer, and see if that helps
All HWS have a safety relief valve, to prevent over pressure from the heated water. This is normally set higher than mains pressure. I do not think it is this, but maybe check it operates.
When on tank water, any over pressure will be returned to the tank, so you would not notice this.
If I am right, on gas, the system heats to a certain point, but only cuts in to full, when in use, ie water flow, so again, you would not notice the problem.
So my conclusion is that on electric, it heats to full temp, and the pressure, while below the relief valve setting, is greater than the abilities of your fittings.
The answer may be a check (backflow) valve on the van, but only if the releif valve functions correctly.
Maybe someone with better knowledge has an answer
I have had a closer look this morning , there is a one way valve between the HWS plumbing and the fill point and so i think this is probably be the culprit.
Will only turn HWS on just before use whilst connected to mains if i can't get a replacement before getting home.
We don't spend a lot of time in CP's so shouldn't be a major issue.
Have you checked the anode?