High gas boiler pressure

davo2001

Hi,

Sorry if this has been questioned a million times but I would like to get some people opinions.

Our gas boiler pressure seems pretty high, 3.5 bar when the heating is off and off the scale when it is on ( see pic )

The overflow outside right behind the boiler is also "overflowing".

I read somewhere that an overflow release value might have been left one (our landlord had someone tinkering with it the other week) he didn't seem to know what he was doing and the issue has only materialised since then.

What might be causing this and it there something I might be able to do myself? The LL now says he cannot get anyone to look at it for a few weeks.

https://imgur.com/lF4ufaD

NickNickleby

This happened to me,so I'll describe what happened and how I fixed it.

My system is sealed, so to stop it exploding it has an escape valve. When the pressure exceeds 3Bar, the valve releases water till the pressure drops. THe pressure always increases when the heating is switched on, but only to about 2Bar.

So why did mine go over-pressure? Someone turned on the cold water feed into the system to refill it, and when finished they forgot to turn off the tap/stopcock/gatevalve or whatever the control device was. So, the mains water was continually trying to enter the system, thereby pushing up the pressure. Then when the heating was turned on, it went berserk.

Here's how I fixed it:
1. I found the mains supply into the system and turned it off.
2. there's a drain valve in my hall, so I carefully drained some water out of it until the pressure dropped to 1.5Bar.

Please bear in mind, I'm not a qualified person, just know enough and lucky enough to get away with it.

Hope this is informative.

nick

jca

NickNickleby wrote: »

This happened to me,so I'll describe what happened and how I fixed it.

My system is sealed, so to stop it exploding it has an escape valve. When the pressure exceeds 3Bar, the valve releases water till the pressure drops. THe pressure always increases when the heating is switched on, but only to about 2Bar.

So why did mine go over-pressure? Someone turned on the cold water feed into the system to refill it, and when finished they forgot to turn off the tap/stopcock/gatevalve or whatever the control device was. So, the mains water was continually trying to enter the system, thereby pushing up the pressure. Then when the heating was turned on, it went berserk.

Here's how I fixed it:
1. I found the mains supply into the system and turned it off.
2. there's a drain valve in my hall, so I carefully drained some water out of it until the pressure dropped to 1.5Bar.

Please bear in mind, I'm not a qualified person, just know enough and lucky enough to get away with it.

Hope this is informative.

nick

That'll sort it although sometimes when the pressure relief valve lifts it has to be replaced as it won't close properly.

davo2001

Thanks for the responses, any idea where the drain valve would be? Or even what it would look like?

Edit: pic:

https://imgur.com/MMVj2LL

jca

Turn off the water at both ends of that braided pipe, that's your filling loop. If you can't find the drain down valve you could open a bleed valve on a radiator. It will take a while but it will let the pressure off the system. You need to do this soon as that sustained high pressure could damage the coil in the hot water cylinder.