Boiler losing pressure after radiator removed, won't fully repressurise

[Ewan1984]

Evening all, really hope someone can give a bit of advice. Basically, my logic combi boiler (6 years old) has always been absolutely fine, hardly ever needs me to repressurise it to 1.5 bar.

A couple of days ago I had a radiator removed because I've got damp in my house and the contractor needed the radiator off before they could do the work.

The plumber said I might need to repressurise the system, which I did. Now, however, the boiler loses pressure within 24 hours and I keep needing to add pressure into it in order to get the boiler to work. Like I say, this has hardly ever happened before and I'm a bit anxious about it given that I've got a young child living with me.

The other issue is that, on the rare occasions where I have had to repressurise, I've always opened the valves and its gone as high as I want. For some reason now, whenever I open the valves, a bit of water gets in and the boiler says its ready to work but, with pressure still under 1 bar, the water stops going in. I've tried closing the valves and reopening but it still doesn't have any water coming in. When I next repressure (24 hours later) it lets a bit of water in again, but once more I can't get it to 1.5 bar.

Very confused because I didn't think simply removing one radiator could cause so many problems! Any likely quick fixes will be appreciated because I won't be able to get the plumber back for a couple of weeks until the work is done and I've plastered / painted the wall.

Thanks for any help or advice

 

[terryplumb]

Does pressure rise to around 3 bar when heating is on ?
Check PRV pipework ,usually a copper pipe external to the premises ,see if any water has been coming out of it.
Check the pipes that go to the valves on the removed radiator position for any sign of leaking.

 

[fixitflav]

Evening all, really hope someone can give a bit of advice. Basically, my logic combi boiler (6 years old) has always been absolutely fine, hardly ever needs me to repressurise it to 1.5 bar.

The other issue is that, on the rare occasions where I have had to repressurise, I've always opened the valves and its gone as high as I want. For some reason now, whenever I open the valves, a bit of water gets in and the boiler says its ready to work but, with pressure still under 1 bar, the water stops going in. I've tried closing the valves and reopening but it still doesn't have any water coming in. When I next repressure (24 hours later) it lets a bit of water in again, but once more I can't get it to 1.5 bar.

You might try repressurising at different times of day. Some areas the mains pressure is lower when demand is high.

 

[MeldrewsMate]

...When I next repressure (24 hours later) ...

There's a clue here, surely you don't expect to have to re-pressurise every day? The water is escaping somewhere.
Check for water leaks...under the disturbed rad, at the safety discharge pipe.
Were you there when the heating was switched on after the radiator was replaced? Was there a period of crashing and banging from the boiler?

Possibles are:
1. Damaged pipe around the disturbed rad (water leak)
2. Faulty/under-charged expansion vessel.
3. A leak elsewhere.
4. Faulty pressure relief valve (how did the contractor de-pressurise the system?)
5. Heat damaged boiler heat exchanger (dry fired?)