Is my boiler's pressure too high?

Ellie83

Wow, that is brilliant info Roger! My oh bled the radiator and we managed to get the pressure down to 1.6 when it was cold. It went up to 2.2 when I put the heating on and is now 2.5, so clearly something is adding water into the boiler!

I have a user's manual and managed to find the installer's manual. I can't understand much of the installer's manual though As for the user's manual, it deals with low pressure problem but not with high pressure :rolleyes:

Next time I will check the guy's credentials thoroughly! They (the repair men!) change everytime though.

We have a gas safety certificate but I don't know how thorough these are as none picked on our boiler's problems. Maybe it is because they aren't directly related to gas?

Anyway, I will bleed the radiator before I go to bed again and I will call the Estate Agent as I really don't know what to do. My dad told me to check if the repair man had closed the water "tap" used to add pressure but I can't find any tap and it is not mentioned in the user's manual

Gah, why is it always us with boiler problems :rolleyes: And why am I so clueless

lovethymini

There should be an expansion tank in the boiler to compensate for the increasing volume of water as it heats up.
If the pressure is going up and staying up, even when it's not heating water, this could suggest it's worth checking that the filling loop is not connected and turned on. The filling loop is the flexible stainless steel hose that connects the mains water pressure to the boiler, and despite the water regulations stating it should be removed once the system is pressurized, most plumbers generally leave them in situ.

Hope that makes sense.

keystone

lovethymini wrote: »

There should be an expansion tank in the boiler to compensate for the increasing volume of water as it heats up.

There WILL be an expansion vessel and it may be within the boiler casing or it may be external.

If the pressure is going up and staying up, even when it's not heating water, this could suggest it's worth checking that the filling loop is not connected and turned on. The filling loop is the flexible stainless steel hose that connects the mains water pressure to the boiler, and despite the water regulations stating it should be removed once the system is pressurized, most plumbers generally leave them in situ.

Hope that makes sense.

Whilst it makes total sense it assumes that the boiler concerned has an external flexi filling loop and not a internal key operated one. In any event the solution is the same.

Cheers

roger196

Go to www.screwfix.com and type in 30327 which is the part number of a flexible filling loop. The "tap" will be a screwdriver slot in the isolation valve. Hope this helps you to identify this part.
Your boiler manual will tell you if you have an internal one or an external one.

keystone

Actually you'll find filling loops with levers like w/m taps as well.

If you have an NRV then the loop does not always need to be disconnected. Don't "adjust" an NRV expecting it to shut the water off. First it won't and second you can't "adjust" an NRV.

Cheers

mickybro

The filling loop should always be disconected from your boiler so there is no chance of a valve leaking and building up excess pressure. The other problem is that if there is excessive pressure it can damage the rubber seals and gaskets in the boiler a more costly problem

Ellie83

The plumber has been here and it is -at the moment- working perfectly fine. The plumber told my o/h that it probably was air trapped in the heat exchanger (not sure it's the exact name though). The heat exchanger was changed at the start of the week so he suspected it was to do with that. He's going to come back tomorrow to check everything is in order.

The pipe does not leak anymore, so it is a good sign! The pressure, at its highest, is 1.8. Hopefully everything has been repaired!

Thanks so much Roger for the picture. I showed it to o/h and we have a loop like that but there is nothing on it for us to turn At least we can ask the plumber tomorrow! Poor plumber, I feel bad to make him work on a Sunday.

Thank you all so much for your help! It is so nice of you to explain and give advice, we are really grateful. Hopefully, this is the last you'll hear of my boiler, although I don't want to jinx ourselves