Bleeding the radiators & boiler pressure (newbie needs h

[rootsrat]

Hi all. First of all - I am a total newbie when it comes to DIY and I have never did much of it, so apologies for any silly questions.

Me and my girlfriend have recently moved into a 2 bed house with CH. We've previously lived in a flat which had electric heating, and so I don't really know anything about CH.

I did some research on web though...

The pressure in our boiler is really high, it oscillates between 2.5 and 3, where 3 is the max the boiler can handle - according to the dial.

Apparently the most common cause of that is air in the CH system. The remedy is to bleed the radiators, which I intend to do as soon as my radiator key arrives (yes, I didn't have one!).

I switched the radiators on tonight to check which ones need bleeding - and the internet teaches us ( ) that it's the ones that are not fully heated at the top parts...

Unfortunately mine were cold at the bottom parts (all of them), and I had to switch the heating off as the pressure was getting to 3.5, which was already at the red mark on the pressure dial.

So my question is - what should I do? Do I bleed them all? Will this cause massive pressure drop and a need to re-pressurise the boiler? I need some guidance and advice, as the nights are getting cold and we really need to start heating the house...

Thanks in advance for any kind advice and help!

 

[ianmcd]

everything you need to know is in the WIKI at the top of this page

 

[45yearsagasman]

Boiler make and model please, and a better description of your system.
How many times is this requested?

 

[PrenticeBoyofDerry]

If you rads are cold at the bottom, it could be that you have sludge in the system, and that means a flush out and chemical cleaner would need to be introduced to help clean out the sludge.
A high pressure reading on the boiler gauge, could mean many things, but I would firstly flush out the sludge with a system cleaner, run system for a few days then drain down again and refill with an inhibitor.

 

[Burnerman]

There are some issues here.....the boiler pressure is too high. 1.5 bar is typical.
Whatever the pressure is, it should stay there.....if its creeping up then the filling loop is allowing fresh water in, or there's an internal fault with the boiler.
The pressure should rise a little when the heating is turned on.
If the boiler pressure rises above 3 bar, the excess water discharges to the outside.
If the pressure increases widely when the heating is turned on, then the expansion vessel needs recharging with air, after checking.
Bleeding water out of the rads will reduce the pressure, and hopefully expell any air at the same time.
There isn't any connection between boiler pressure and domestic hot water - but if the boiler pressure is very low, it probably won't ignite anyway!
I think you need the system fully checked by a professional as there's a good few things to check here.
John

 

[rootsrat]

everything you need to know is in the WIKI at the top of this page

I did look through the wiki pages before posting - both Boilers and Heating Systems sections, but couldn't find any useful information unfortunately. Perhaps I don't know where to look...

Boiler make and model please, and a better description of your system.

Vokera Compact SE.

3 stories house, 1 radiator in each room, I don't know what other info you require...

If you rads are cold at the bottom, it could be that you have sludge in the system, and that means a flush out and chemical cleaner would need to be introduced to help clean out the sludge.
A high pressure reading on the boiler gauge, could mean many things, but I would firstly flush out the sludge with a system cleaner, run system for a few days then drain down again and refill with an inhibitor.

This is definitely something I won't be able to do myself unfortunately.

There are some issues here.....the boiler pressure is too high. 1.5 bar is typical.
Whatever the pressure is, it should stay there.....if its creeping up then the filling loop is allowing fresh water in, or there's an internal fault with the boiler.
The pressure should rise a little when the heating is turned on.
If the boiler pressure rises above 3 bar, the excess water discharges to the outside.
If the pressure increases widely when the heating is turned on, then the expansion vessel needs recharging with air, after checking.
Bleeding water out of the rads will reduce the pressure, and hopefully expell any air at the same time.
There isn't any connection between boiler pressure and domestic hot water - but if the boiler pressure is very low, it probably won't ignite anyway!
I think you need the system fully checked by a professional as there's a good few things to check here.
John

Yeah, the last proposed option seems the best then...

Thanks for all your replies guys, I think I'll call my agency and request for someone to come over and do a full system check.