Hi All,
Apologies in advance that this is a topic that's already been discussed to death, but just wanted to get my logic double checked if possible..
We have a 3 storey, 12 radiator house with a Telford Tempest unvented cylinder and Worcester Bosch boiler. The Radiator circuit is around 50% 'old' (>10 years) and 50% new (<1 year). The cylinder and boiler are just over a year old.
We had an electrician in last week doing some re-wiring and I noticed that the pressure gauge above the external expansion vessel had dropped to almost around 0.5bar of pressure. I topped up the system, to it's usual 1.5bar, but the next morning it was back down to 1bar again. My immediate thought was that the electrician had probably put a nail through a pipe when he relaid the floorboards.
As a check, I've taken up all the floorboards on the 2nd and 3rd floors that are anywhere near a CH pipe (and that are accessible) and have found no evidence of nail/screw through a pipe or any leak.
The pressure is still dropping and it takes around 15 seconds to repressurise. With a crude kitchen-tap test, I think this is about 2.5 litres of water I'm adding into the system each time (daily/every 2 days).
I would have thought that if I was losing this much water through the CH pipework, there would be some visible evidence of it?
There are 3 radiators on the ground floor which the pipework runs briefly under the flooring for. I've not lifted those boards yet, but seems unlikely they would have suddenly sprung a leak? The electrician hasn't been doing any work on the ground floor.
I've checked the external drain from the pressure relief valves and it's absolutely bone dry.
To save taking up more floorboards, I've tried another test today whereby I turned off the CH completely, but left the HW circuit on. Looks like we're still losing pressure.
From what I've read, I think my investigations so far would isolate the problem to 1 of 3 areas?
1. Expansion Vessel failure. I think this is unlikely, as the pressure just falls, there's no increase in pressure followed by a fall. Is my logic correct there?
2. Heat exchanger failure in the Worcester Bosch. I've not checked the condensate drain - perhaps this would be a good next step? Is it likely that this would have a failed suddenly on a 1 year old boiler?
3. Leak inside the HW cylinder. The hot water is running 'clear', if there was a fault inside the cylinder, would you expect some visible contamination of the hot water?
Final check I've made is that the highest radiator in the system doesn't seem to be collecting air. If if try and bleed it, water comes out almost immediately.
Anything else I should check?
Apologies in advance that this is a topic that's already been discussed to death, but just wanted to get my logic double checked if possible..
We have a 3 storey, 12 radiator house with a Telford Tempest unvented cylinder and Worcester Bosch boiler. The Radiator circuit is around 50% 'old' (>10 years) and 50% new (<1 year). The cylinder and boiler are just over a year old.
We had an electrician in last week doing some re-wiring and I noticed that the pressure gauge above the external expansion vessel had dropped to almost around 0.5bar of pressure. I topped up the system, to it's usual 1.5bar, but the next morning it was back down to 1bar again. My immediate thought was that the electrician had probably put a nail through a pipe when he relaid the floorboards.
As a check, I've taken up all the floorboards on the 2nd and 3rd floors that are anywhere near a CH pipe (and that are accessible) and have found no evidence of nail/screw through a pipe or any leak.
The pressure is still dropping and it takes around 15 seconds to repressurise. With a crude kitchen-tap test, I think this is about 2.5 litres of water I'm adding into the system each time (daily/every 2 days).
I would have thought that if I was losing this much water through the CH pipework, there would be some visible evidence of it?
There are 3 radiators on the ground floor which the pipework runs briefly under the flooring for. I've not lifted those boards yet, but seems unlikely they would have suddenly sprung a leak? The electrician hasn't been doing any work on the ground floor.
I've checked the external drain from the pressure relief valves and it's absolutely bone dry.
To save taking up more floorboards, I've tried another test today whereby I turned off the CH completely, but left the HW circuit on. Looks like we're still losing pressure.
From what I've read, I think my investigations so far would isolate the problem to 1 of 3 areas?
1. Expansion Vessel failure. I think this is unlikely, as the pressure just falls, there's no increase in pressure followed by a fall. Is my logic correct there?
2. Heat exchanger failure in the Worcester Bosch. I've not checked the condensate drain - perhaps this would be a good next step? Is it likely that this would have a failed suddenly on a 1 year old boiler?
3. Leak inside the HW cylinder. The hot water is running 'clear', if there was a fault inside the cylinder, would you expect some visible contamination of the hot water?
Final check I've made is that the highest radiator in the system doesn't seem to be collecting air. If if try and bleed it, water comes out almost immediately.
Anything else I should check?
