MegaSack DRAW - This year's winner is user - rgwb
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Believe it or not, I've never done this job before. Is it normal to have to do it in stages? I'm doing it until the hissing stops/water comes out. Then I go back to it and there's more air coming out.
Any tips? Not my house btw. A studio complex, so don't have access to a few rads behind locked doors.
Sounds about right. The only other thing to remember is to top up the pressure in the system afterwards
Thanks.
That's the valve next to the pressure dial right?
Turn the heating off first. You can't do it if the pump is running.
All good advice. Thanks. Had it off initially to do all of them. Then got it running and have been going round periodically to re-check (turning the rad off first)
Error?
This has probably been done rarely btw. If at all, heating system looks very new. My rad was luke warm at best so cold has forced me to investigate.
Warming up now though!
I am not a plumber, but my understanding is that if the pump is running you can end up sucking air in rather than letting it out. I could be wrong and I don't really follow the logic of that, but it's what I was told.
Here's a super interesting photo of the valvy bits. Which knob to turn?
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They’ll likely both need to be opened , the handle should be in line when the valve is open. You’ll hear the water flowing and the see the pressure rise so open one and that doesn’t work open the other two.
Depending on how much air is in the system you might have to top it up before all the roads are bled. Then don't forget to top it back up to 1bar when you've finished bleeding.
Looks pretty low pressure atm!!
The plot thickens!
Top it up? With what? Engine oil? Coolant?
Top it up with water, via and the 2 valves in your pic
As mentioned, both valves need to be opened to allow the water from the mains to top up the system.
The 1 bar pressure will be for a cold system, this will be higher if the system is hot.
Right. Got it. Thought for a minute I had to actually pour something in.
Opened up both valves until the needle got to about 2.5. Then I chickened out and closed it. Was getting a bit 'Das Boot'. Afraid something would blow.
Why did you ignore the 1 bar instruction.
Because it sounded like water was still coming through. And that post up there about it being hot. Do I need to relieve it somehow?
🙄 yes let it out by bleeding a radiator is the easiest way
Ahhh... beginning to see how all this works now. I should become a plumber.
1) with cold heating ensure the pressure is say 1 bar (most will have a needle at a set point like in your pic)
2) I've always bled radiator farthest from the boiler and down stairs
3) bleed all radiators till water comes out (as you've done) but check on the pressure after each one to make sure it's not dropped to 0bar
4) top up pressure to 1bar once completed and run heating
5) if cool radiators persist, either repeat (once heating is cold again) or get a plumber in
Thanks chaps. All rads hot. just relieving a bit of pressure till she's steady.
This is what a lifetime of renting does. My knowledge of central heating amounts to On/Off.
To relieve pressure you can turn the red knob above the pressure gauge, it has a spring return so you only need to turn a tiny amount anti-clockwise and hold until it reaches 1 bar then just let go to stop.