Combi Bioler Pressure Loss

[fullern]

Good morning all,

We have a combi boiler CH and HW system in our house, and everything seems to work fine. We get hot water and heating, but the pressure on the boiler, despite being topped up numerous times keeps dropping from 1 bar (manufacturers recommended pressure) to 0 (it takes about an hour and a half to drop).

Some general info;
We moved in about ten months ago and the boiler was already plumbed in. I top it up using the induction loop which is constantly attached to the boiler. As far as I can tell we have no leaks on any of the visible pipes (some of the pipes run under a concrete floor so can't check everything).

We have installed a new radiator last week, but the pressure was dropping before this was installed. Also, not sure if relevant but I noticed whilst bleeing the radiators that one of the insert plugs for the bleed valve doesn't tighten - so that when you use a bleed key to open the valve, the metal insert just keeps spinning round until you use some pliers.

My question is, whilst the system is working should I be worried about the fact there is no pressure? Are there any obvious things I can look at before calling out a plumber (the house is costing us a fortune at the moment and with Christmas coming I would much rather leave things if possible).

thank you for any help, I am slowly falling into despair with this house!

N.

 

[dcawkwell]

Check you haven't a leak outside via the pressure relief pipe.

Otherwise there is a leak someone in the piping.

You can pressurise the boiler
You can then turn the boiler off and isolate it with the valves
underneath the boiler (22mm pipe central heating ones).
The pressure should keep if it still drops there is a problem in the boiler.
If it is steady there is a leak in the house.

 

[fullern]

Good thinking I will try isolating the boiler from the system to see what happens.

Why does the CH and HW still work though even if the pressure is at 0?

many thanks

N

 

[dcawkwell]

Good thinking I will try isolating the boiler from the system to see what happens.

Why does the CH and HW still work though even if the pressure is at 0?

many thanks

N

It depends on the boiler. Some earlier boilers didn't monitor the pressure in the boiler.