Unvented system pressure

16 Apr 2008
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United Kingdom
I was topping up the pressure on my unvented central heating/hot water system. I opened the flexible filling loop to top it up, it was taking AGES and I forgot to close it until the next day.

Now my boiler is at pressure level 3, the red mark.

is this dangerous and is there a way to reduce it?
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Just bleed off a little water from any radiator until it gets to the correct pressure. (y)
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I think I'm right in saying that the dial won't move until the system is full, at which point it pretty quickly moves as it equalises with mains pressure.

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