combi boiler pressure loss

[nyc]

Hi

I've just had a new combi boiler installed. I have recently noticed the pressure dropping gradually - it has dropped about 0.2 bar over a 3-4 day period. this happened when we didnt use the boiler for 3 days and also when we used the boiler for CH and hot water for 3 days.

The pressure used to stay constant at about 1.2 (the level it was filled up to) when the system was cold but now it seems to fluctuate between 1.2 and 1.

Is this normal? Or will this loss of pressure gradually get worse and fall below 1?

today is the 4th day running the central heating since we started keeping an eye on the pressure. We will see if it drops below 1 after the system cools down.

Having read some of the posts on this forum, we have checked for leaks in the obvious places - rad valves, prv etc. Cant see anything wet.

Thank you for any light you can shed on this.

 

[adlplumbing]

ask the installer to come back and have look as s/he cares for his rep then they will see if they can find it rectife the problem
also check the prv (blow off pipe at the back)

 

[Happyplumber]

This is new install,so maybe some settling down,did you bleed the rads and top up the system?

If not then call in the installer and ask them to have quick look around,if we were in this sitaution then we would definetly pop around to check up on the system,always a good thing for customer relations and for peace of mind

 

[holty]

as happyplumber suggested have you bled the rads.i always advise customers for the first couple of weeks to at least bleed the rads.and check the pressure as it can take a while for a system to settle as mentioned.but also as mentioned any decent company will pop round to give peace of mind.dont forget little pockets of air find there way to the boiler and other air release valves.so in doing so, pressure will be lost.not always the case on certain systems.but due to design of pipework etc.there will be teething problems with air.even on sealed systems.

 

[nyc]

Thank you. We did take rads off for decorating. the installers took them off and put them back on for us. they said they bled the rads and topped up the system. They said they dont know what it could be as they have checked all the rad valves and the prv pipe on the boiler and they are all dry.

I just wondered if these fluctuations were natural variations or whether they point towards something worse. we've just had a new kitchen installed and new floors....so really hoping its not a leak somewhere under the floor.

i guess we can call them out again and ask them to check again. I'm just concerned about what to do if they cant find anything.

Cheers

 

[nyc]

thanks holty.

just want to clarify...shall we continue to bleed the radiators and top up the system until it settles down?

cheers

 

[nyc]

Also, can i ask another question if you dont mind? The by-pass radiator and the kitchen radiator (a column 2m tall radiator) are not installed level - they slant a bit to one side. I noticed that the bypass radiator does not heat up evenly -- the top corner of lower side is slightly less hot than the other side. Column radiator seems to have even heat.
• Could this create an issue with water flow or air in the radiators that might cause the pressure drop?
• Do they need to be levelled out – will they have an adverse effect on the CH system in time if not levelled?

 

[holty]

alarm bells are starting to ring.when rad/towel rad cant be installed correctly.love to give helpful advice but i would strongly advise to at least get the people who installed that rad to rectify it.

 

[nyc]

thanks. will get them to rectify the rads. i'm just nervous about taking the rads off and on before the system has settled down.

 

[Whitespirit66]

Also, can i ask another question if you dont mind? The by-pass radiator and the kitchen radiator (a column 2m tall radiator) are not installed level - they slant a bit to one side. I noticed that the bypass radiator does not heat up evenly -- the top corner of lower side is slightly less hot than the other side. Column radiator seems to have even heat.
• Could this create an issue with water flow or air in the radiators that might cause the pressure drop?
• Do they need to be levelled out – will they have an adverse effect on the CH system in time if not levelled?

If rads aren't level, then air can become trapped which will be difficult to bleed if the bleed valve is on the lowest side. You may get a trapped air pocket that could lead to uneven heat distribution.

How far out of true are the rads?

 

[nyc]

Thank you.

They are quite a bit off level but the bleed valves on both are at the high end.

top corner of the lower side of the bypass radiator seems cooler than the rest of the radiator...so i guess that means trapped air.

thanks again