New Combi - Pressure Loss

Hi All,

Wondering if anyone can advise....

We recently had our tanked system replaced with a combi. Baxi Platinum HE. All worked well for a month or two.

However, I recently changed a radiator in the systemt to a larger one. This resulted in lots of air in the system, generally collecting at one of the radiators close to the boiler, so I bled it all off.

Since then, I ahve had to regularly top up the water pressure in the boiler. It seems to lose something like 0.1/0.2bar a day.

I am sure that there are no leaks around the valves of the new rad. I havent seen anything coming out of the pressure relief drain either.

I dont know a huge amount about these things, and dont really want to get the installer out if its soemthing obvious I can sort quickly myself on the boiler?

I dont want to keep topping it up indefinately as I know that it isnt good for the system.

The only other thought is that I could check the pipework under the radiators in case I distrubed it and caused a small leak when I changed the radiator. There are no other signs of leaks anywhere, but I am yet to look under all the floorboards.

Any pointers much appreciated!

sounds like air definitely getting in somewhere.

I hate combi boilers. Hope you get some stronger help soon

Only thing that has changed is the new rad, that and the pipework in the vicinity would be the first port of call to check. Wouldn't take a lot to drop the pressure.

When you changed the rad, was any of the pipework/valves changed?

Well, the installer changed the rad and added TRVs, but i just opted to change the single convector rad for a double convector rad. I wonder if I yanked the pipedwork a bit and disturbed a joint under the floor. Will get a few of the boards up and have a look....