Boiler Pressure

22 Mar 2006
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United Kingdom
Hi All

Vaillant ECOMAX 828E

My boiler pressure varies when heating is on and when heating isn't on. Isn't the pressure supposed to be static at 1.5 bar at all times. Is this variation acceptble or is there some fault with the system. I would be grateful for advice to help me locate and fix the problem (if there is one). Thanks in advance
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Most boilers are around 1/1.5bar when cold, rising too around 2bar when hot. Normal.
How much is it varying? about 0.2 bar is acceptable. Are you judging this just by the gauge or the actual pressure reading when you press the 'minus' button?
Sorry mis-understood your question :oops: clf is correct. I always leave my Vaillants on 1.2bar cold
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thee will learn lad

we have all done it BTW ;)
gas4you said:
Sorry mis-understood your question :oops: clf is correct. I always leave my Vaillants on 1.2bar cold

Hi "gas4you"

The instruction label on the boiler says pressure to be at 1.5bar. Pressure kept going down over 4/5 days. I called the engineer he found a leak and fixed it. Since then I have been checking pressure daily and found when boiler is cold the pressure guage reads 1.5 bar when boiler is hot the pressure goes to 1.7bar.

Do you think I should reduce the pressure to 1.2 bar.
No, its fine as it is basecoat, if it fall's below 1bar then it aint fine.
Is not rocket science all pressures are approx or individual preferences. If pressure gets too low, around 0.3, boiler will fault to F22 and cut out.

I would expect pressure rise by about 0.2 bar on pump start up on these as there is a sensor that expects this rise, and if it doesn't see it it can also fault out.

I would expect a larger increase than 0.2 between system cold and hot. I would expect to see btween 0.5 & 1 bar dependant on size of system :)

gas4you, kevplumb,clf-gas for your response to my boiler pressure problem. Good on all of you. I can return to my routine weekly 2 second check. Cover down pressure OK. All good. Back to grind stone lifes ups and downs.

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