C
cholma
Hi,
We moved into a house a number of weeks ago. Rapidly found that the boiler had some pressure problems - i.e. when CH on the pressure rises quite quickly and eventually starts venting water.
Had an acquaintance that's a gas engineer (installed and serviced the boiler in our previous house) initially recharge the expansion vessel, and said that it might need replacing. After trying (and failing) to get him to spare some time to come around and look at it, went with a different guy.
He came around yesterday (by which time the pressure gauge has also failed), having looked at it last week and said that the PRV was definitely knackered. Hoped that the replacement of the PRV and recharge of the vessel would suffice.
He fitted the PRV and fired up the CH for about 20 mins., during which the pressure went from 1 bar to 2.25. He adjusted the boiler thermostat to 4, so that the boiler clicks down/up to keep the pressure between approx. 2 and 2.3 bar, until he can fit a separate vessel. He said that the PRV was now fine and was not dripping.
Turned the CH off after 40 mins., and didn't use until morning. HW off. The pressure gradually went down (over 6 hours before bed) to 0.75 bar. Most of this is probably because when I turned the CH on this morning even though pressure reached 2.3 bar, the PRV was venting (quite a lot of) water outside.
Before I turned on the CH I'd checked the pressure gauge, and it read approx. 0.7, so it had gone down (with no activity for approx. 14 hours) approx. another 0.05 or 0.075 bar overnight (over approx. 7 hours).
Couple of questions :-
1. Rang the guy. Said that the venting under 3 bar is because the expansion vessel is so knackered. Told to nurse the CH and just gently top up the system as required until he comes around to replace expansion vessel.
Q: Is venting under 3 bar set on PRV possible because of the expansion vessel ?
2. Found some water on the floor under the boiler, on the right-hand side. Seems to be a few drops every 5-10 mins., but not sure how long carries on after the boiler has switched off. Guy said that this is probably a problem with the union of the new PRV in the boiler, and will come around to fix.
Q: Would, say, 12-15 drops per hour account for a pressure drop of 0.075 bar over 7 hours ? I'm nervous that the boiler problems have hidden a leak in the pipes somewhere, but I don't want to start panicking and get in leak detection unnecessarily.
We moved into a house a number of weeks ago. Rapidly found that the boiler had some pressure problems - i.e. when CH on the pressure rises quite quickly and eventually starts venting water.
Had an acquaintance that's a gas engineer (installed and serviced the boiler in our previous house) initially recharge the expansion vessel, and said that it might need replacing. After trying (and failing) to get him to spare some time to come around and look at it, went with a different guy.
He came around yesterday (by which time the pressure gauge has also failed), having looked at it last week and said that the PRV was definitely knackered. Hoped that the replacement of the PRV and recharge of the vessel would suffice.
He fitted the PRV and fired up the CH for about 20 mins., during which the pressure went from 1 bar to 2.25. He adjusted the boiler thermostat to 4, so that the boiler clicks down/up to keep the pressure between approx. 2 and 2.3 bar, until he can fit a separate vessel. He said that the PRV was now fine and was not dripping.
Turned the CH off after 40 mins., and didn't use until morning. HW off. The pressure gradually went down (over 6 hours before bed) to 0.75 bar. Most of this is probably because when I turned the CH on this morning even though pressure reached 2.3 bar, the PRV was venting (quite a lot of) water outside.
Before I turned on the CH I'd checked the pressure gauge, and it read approx. 0.7, so it had gone down (with no activity for approx. 14 hours) approx. another 0.05 or 0.075 bar overnight (over approx. 7 hours).
Couple of questions :-
1. Rang the guy. Said that the venting under 3 bar is because the expansion vessel is so knackered. Told to nurse the CH and just gently top up the system as required until he comes around to replace expansion vessel.
Q: Is venting under 3 bar set on PRV possible because of the expansion vessel ?
2. Found some water on the floor under the boiler, on the right-hand side. Seems to be a few drops every 5-10 mins., but not sure how long carries on after the boiler has switched off. Guy said that this is probably a problem with the union of the new PRV in the boiler, and will come around to fix.
Q: Would, say, 12-15 drops per hour account for a pressure drop of 0.075 bar over 7 hours ? I'm nervous that the boiler problems have hidden a leak in the pipes somewhere, but I don't want to start panicking and get in leak detection unnecessarily.
