How should all the boiler taps look when in correct, normal position

[Brigadier]

Rubbish the pressure is rising because the filling loop has been left turned on

I addressed this possibility in my post #6.

But, without photos, I specifically stated that I would back out and leave it to the pros.

 

[Wantstoknow]

Thanks so much everyone! It took me a minute to work out rad was radiator

I've just bled them all in an effort to get the pressure down but as at least that right black tap was open, it kept rising.

I've just bled the bathroom one again and the pressure has reduced to 1bar...

You're all AMAZING and have my deepest appreciation

 

[Madrab]

As suggested, the OP's issue is that the filling loop has been left open. The boiler has either an internal or external expansion vessel (EV) that absorbs the CH water pressure rise when it's heated, that keeps the system pressure stable. There may be a small rise in pressure as the system heats, if there is a mismatch between the system pressure and the EV pre charge pressure but not the rise that this boiler is seeing.

There may be another issue where the EV needs re-charged but that's further down the line here.

 

[Brigadier]

Glad madrab and ianmcd sorted your worries

 

[Wantstoknow]

Still rising & staying that way when I fire the central heating up. I've a feeling the wee left-hand side tap should be pointing up & down (the opposite of the way the trap directly facing it is pointing, if that makes any sense?)

 

[Madrab]

OK, has it stopped rising on it's own though when the system isn't on? If so then we need to move to the next step. If the pressure doesn't rise with hot water but it does rise when you put the central heating on and it goes over 2.5bar then the Expansion Vessel (EV) needs checked for correct pre-charge pressure. They can lose pressure over time.

Just to clarify too, I'm sure that filling loop system needs 2 valves left in the open position for the system to fill, not just one, so I'm afraid the plumber wasn't correct to start with. We do need to know the boiler make and model. Would it be a Potterton/Baxi? (Promax/Heatmax?)

If the expansion vessel does need charged then it's really a job for a professional but lets get the filling loop valves in the correct position first.

 

[Madrab]

BTW, if it is a Potterton/Baxi which it looks like, then the tap on the right needs to be at right angles and the tap on the left needs to be vertical for them both to be in the off position.

 

[mattylad]

I thought it was against the regs to leave a filling loop in permanently like that?

 

[ianmcd]

I thought it was against the regs to leave a filling loop in permanently like that?

what regs are you referring to ?

 

[mattylad]

I have no idea because I'm not an rgi however I do recall reading, possibly on here - statements that were to the effect that the loop should be disconnected.
Suggestions that this is why WB combi's have that god awful plastic key (that's currently broken in place in mine lol).

 

[Madrab]

Best practice is to remove the braided hose so the user can't interfere with it, over fill the system, leave valves open etc, typically it's the same with that type of integrated loop - hence the caps hanging from it so they can be fitted when the com pipe is removed - but there isn't a reg that says so. That and there's too many crap installs where the system starts to lose pressure and the client needs to keep topping it up.

The regs only cover the fact that a filling loop needs to have a check valve so there's no backflow into the mains water.