combi boiler losing pressure

[townsmcp]

Yeah - I always make sure that I power up the boiler straight after toping it up - if it goes over the 2.5 mark I release some water from a rad in the house.

Thats the prob I have - cant see any leaks anywhere in the house or on the outside overflow pipe - before the fitting of the boiler I had an old tank system, got that taken out and the boiler moved to the loft and got the rad valves all changed (unfortunately my downstairs is a concrete base house but havent had any damp patches/mould or any other telltale signs of a water leake) and ever since the system was about a year old ive been having to top up water more frequently.

JamesT

 

[sonray ltd]

>ive been having to top up water more frequently & concrete floors

don't sound good.

see this many times when a gravity system is changed to a pressurised system and the pipework don't like it.

you can have a weak pipe/joint for yrs on gravity but soon as converted to pressurised it gives in.

 

[townsmcp]

Damn - old system was in for about 25 years before this new boiler was put in. Are there any ways to make sure there are no leaks/bad joints in old pipe work apart from the obvious of ripping the whole house apart/ taking up all concrete floors etc? I take it the cost to finally sort this would be very high to fix

JamesT

 

[sonray ltd]

no easy way.

 

[marshr02]

I'm no expert, but what about using gate valves (low resistance to flow) or similar to divide your system into zones; say upstairs & downstairs. Then shut a zone off for a few days or so & see if pressure drop keeps happening. If there is one leak rather than small leaks all over you could chase down it's rough position & limit how much floor etc you rip up. Obviously the gate valves would be installed in easy positions, such as the flow & return pipes going upstairs on surface of plaster.

 

[unfinishedsweet]

It's not easy to check the potential leaks but you could eventually find some discreet places to cut off the under concrete section of pipework to mess a bit with them, for instance fit two valves at the edges of the pipes, then screw a pressure gauge on one of them, then connect a mains to the second, fill the section with water, close the valve mains is connected to and watch the gauge if there is any loose or not. Bleed the rads and close their valves. You could eventually connect the gauge to a rad's valve, but it's harder to bleed the section. This solution would damage uncovered pipework aesthetics, cause you would have to connect the pipes again. Also you would have to be sure each section of under concrete pipework is isolated, the valves are closed etc. Not perfect, but always _some_ way to check for invisible leaks.

 

[ice cold]

Ice Cold - did you get a reply about this?

James T

After a couple of days of the pressure dropping to 0 and topping it up the problem seems to have gone away.

I'm guessing that as Mike said, there was some dirt on the PRV and it must have cleared itself. Don't know if this is a likely explanation, but I've checked the boiler and there hasn't been a drop in pressure since.

Thanks to all for advice and suggestions anyway.

 

[intergasman]

If Your PRV is ok and you have no leaks on the system test the pressure vessel on the boiler it might have lost it's charge.!!

 

[mike4369]

If Your PRV is ok and you have no leaks on the system test the pressure vessel on the boiler it might have lost it's charge.!!

I have a similar problem as descibed here ( posted as a separate thread) and will try the prv fix first - but to what pressure do you recharge the expansion vessel. My boiler = Ferroli F30 COMBI.

 

[mnad]

Hi Guys,

I have an Ariston Micro GENUS HE bolier (24months old) ... it seems to be losing pressure around 0.5bar every 6hours or so ....

iv been loking around for possible leaks without success ...

However there's a drip at the water Mains internal stopcock ... would that be a possible cause?