Normal pressure drop variation help

[Dingdangdo]

Hi folks. A quick question about boiler pressure. During the day we obviously use hot water and heating and the pressure when cold on the system reads about 1.4bar. If we have been out all day and not used the heating or any hot or cold water I can see that the pressure has dropped a tiny bit to say 1.3bar. Once I have run the hot tap to fill up the sink then the pressure settles again at 1.4bar with no heating on. Only when we haven't used the hot water or heating for nearly a full day does the pressure drop slightly to 1.3bar. Is this just simply due to the pipes in the house being colder for a longer period than normal? Thanks in advance. There are no visible signs of any leaks around the rads etc

 

[terryplumb]

Fairly normal for incremental pressure fluctuations. As long as pressure doesn't fall dramatically or rise to Over 2.5bar there is nothing to worry about.

 

[fixitflav]

Hi folks. A quick question about boiler pressure. During the day we obviously use hot water and heating and the pressure when cold on the system reads about 1.4bar. If we have been out all day and not used the heating or any hot or cold water I can see that the pressure has dropped a tiny bit to say 1.3bar. Once I have run the hot tap to fill up the sink then the pressure settles again at 1.4bar with no heating on. Only when we haven't used the hot water or heating for nearly a full day does the pressure drop slightly to 1.3bar. Is this just simply due to the pipes in the house being colder for a longer period than normal? Thanks in advance. There are no visible signs of any leaks around the rads etc

It's due to expansion of the water on heating causing a flow into the expansion vessel, so compressing the air (and vice versa on cooling) As terry says, nothing to worry about.