Combi boiler pressure going down fast

jsmoke · 1 Dec 2019 at 08:41

Within a few days goes from 2 to 0 bar, I assume it must be a leak, is this a big job, what else other than leak would cause this drop in pressure?

xb8browney · 1 Dec 2019 at 08:52

Check the pipe that goes outside if you see water where it's probably the PRV that needs replacing, if not possibly a expansion vessel recharge.

DarrenM343 · 1 Dec 2019 at 09:20

If it's a leak it could be a big job but there are tools out there to help. There are also specialists that can help too. One method is to use a gas and use equipment to listen for the leak.
Having a go yourself can include a combination of using a thermal imaging device (rent one) which should at least help you track the pipework, a damp meter and even a small camera on a flexible wire which will allow you to drill holes near the pipework or where the joins are and then have a look. These are things other forum members posted when I asked a similar question a while ago.
I've still got a leak somewhere in my home but for a few weeks it's settled down, a little while after my plumber used leak sealer in the system. Bit busy at the moment and now hoping I can get through the winter and spend some time on it next year. One of the issues I have is that the boiler is not really up to spec of the house. Think my plumber said it has a 6 litre expansion vessel but the house has 13 radiators, although some are quite small, so the pressure can rise quite a lot when the heating is in use.

jsmoke · 2 Dec 2019 at 10:49

DarrenM343 said:
If it's a leak it could be a big job but there are tools out there to help. There are also specialists that can help too. One method is to use a gas and use equipment to listen for the leak.
Having a go yourself can include a combination of using a thermal imaging device (rent one) which should at least help you track the pipework, a damp meter and even a small camera on a flexible wire which will allow you to drill holes near the pipework or where the joins are and then have a look. These are things other forum members posted when I asked a similar question a while ago.
I've still got a leak somewhere in my home but for a few weeks it's settled down, a little while after my plumber used leak sealer in the system. Bit busy at the moment and now hoping I can get through the winter and spend some time on it next year. One of the issues I have is that the boiler is not really up to spec of the house. Think my plumber said it has a 6 litre expansion vessel but the house has 13 radiators, although some are quite small, so the pressure can rise quite a lot when the heating is in use.

Looks like it's the boilermag filter that's leaking. It looks like the leak is coming from the bottom, the drain hole, should I just tighten this up or will a seal have likely gone?