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Ideal combi small loss of pressure

Hi, I had an Ideal C30 combi fitted about two months ago and I have noticed that it sometimes loses a really small amount of pressure. I fill the loop until it is on exactly 1 bar and sometimes when I look at the gauge it has dropped about 1mm below and then another day it will be back up to 1 bar again. I have not used my central heating, so does this mean I am losing water from somewhere or is a tiny fluctuation in pressure normal? When it was installed the plumber accidentally let the pressure build up too high and the pressure valve opened and water shot out of the overflow pipe outside. Could this have caused any damage to the boiler? Any help would be most appreciated as I know very little about plumbing and boilers.

Kind Regards, Kev.
 

Millsy 82

Plumber
Gas Engineer
If you top it up when the boiler is warm/hot then when the boiler is cold it will show a small drop.

If you have a substantial drop .5 bar then call them back.
 

scott_d

Plumber
Gas Engineer
Constantly going down means a leak
Down and back up sounds like fluctuation
How many radiators are in your house?
 
If you top it up when the boiler is warm/hot then when the boiler is cold it will show a small drop.

If you have a substantial drop .5 bar then call them back.
Thanks for your quick reply Millsy 82. I will try topping up when cold and see if it stays stable.

Kind regards, Kev.
[automerge]1567263588[/automerge]
Constantly going down means a leak
Down and back up sounds like fluctuation
How many radiators are in your house?
Constantly going down means a leak
Down and back up sounds like fluctuation
How many radiators are in your house?
Hi Scott_d. Thanks for your reply. I have nine rads in the house, but have only had the heating on once since the boiler was fitted to check for leaks and couldn't see any. The pressure literally only goes down about 1mm under the 1 bar, then it will go back to 1 bar and then when I look again it'll be slightly under again, so hoping it is just fluctuation as you have said.

Kind regards, Kev.
 
Last edited:

king of pipes

Esteemed
Plumber
Gas Engineer
Chances are it's just a fluctuation caused by temperature changes top it up to 1.2 to 1.5 bar and monitor again if it was leaking it would drop more over a period and not go back up
 
Atmospheric pressure fluctuates up and down within a range of circa 0.1bar (i.e. +/-5%). So, even if the water pressure inside the system is constant, you'll see day-to-day fluctuations on the gauge of this order.
 
Chances are it's just a fluctuation caused by temperature changes top it up to 1.2 to 1.5 bar and monitor again if it was leaking it would drop more over a period and not go back up
[/QUOTE
Chances are it's just a fluctuation caused by temperature changes top it up to 1.2 to 1.5 bar and monitor again if it was leaking it would drop more over a period and not go back up
Thank you, I will try this.

Kind regards, Kev.
[automerge]1567270670[/automerge]
Atmospheric pressure fluctuates up and down within a range of circa 0.1bar (i.e. +/-5%). So, even if the water pressure inside the system is constant, you'll see day-to-day fluctuations on the gauge of this order.
Excellent!! Thanks for explaining this to me.

Kind regards, Kev.
 
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