Vaillant Combi Boiler -High Pressure? How get down?

[trinabob]

Hi

In desperate need of some advice!!

the pressure of my vaillant turbomax boiler is very low, about 0.8, and therefore the water is trickling out the taps and won't come out of the electric shower. I think the system needs filling with some water from what i have been reading. the filling loop is built into it and i have turned it a quarter turn to allow the water to come in. this doesn't seem to have had any effect though, it doesn't seem like any thing is coming in i.e no noise and the pressure gauge isn't moving.

so, can anyone offer any assistance? is simply turning this screw head enough or should i be opening some tap somewhere?

thanks for any advice

Kate

 

[ChrisR]

The pressure IN the boiler on the gauge should be about 1, but doesn't affect the pressure at the taps AT ALL.
It sounds like your mains water has failed!
How's the cold at the kitchen tap?

0.8 is ok for now, so close the filling loop, otherwise it might shoot too high when the mains comes back on.

 

[Agile]

To open the filling loop you have to open TWO valves by 90°.

If your mains water has failed then the pressure will not increase though.

Tony

 

[chrishutt]

To open the filling loop you have to open TWO valves by 90°.

Not necessarily. On many Turbomaxes the filling loop is controlled with just the one valve with the annoying loose key which is inclined to fall out and get lost. There may be a second valve but it is usually left open.

 

[trinabob]

thanks for all your replys, turns out it was a mains water problem that took them a long time to sort out!

however, now i have another problem in that with all my messing the water pressure is sky high. if i open the filling loops will this take out the excess water and the pressure drop back down to between 1 to 1.5? if this is correct then will it take a while to run out or will it do this quite quickly?

i'm sure there will be a few people reading this and shaking there heads at me for fiddlin with it in the first place! i do appreciate your help!!

thanks kate.

 

[Beans-on-Toast]

Stop fiddlin with it as 1 - 1.5 bar is where it needs to be, besides if the pressure is too high there is a built in mechanism that allows the excess to exit....!

 

[trinabob]

LOL! i wish i'd never touched the soddin thing in the first place! i left it alone last weekend when i couldnt get the pressure up from 0.8. Been away all week, mum asks me to check it tonight and now the pressure is 3.0!? Dont know how it went up or how to get it back down now! so if i leave it it will go down on its own will it?

 

[chrishutt]

You may have left the filling loop connections open! Is water dripping out of the copper pipe that goes out through the wall below the boiler? That is the discharge pipe from the PRV that stops the pressure rising above 3 bar.

 

[noodlz]

It won't go down on its own. As Chris says, make sure filling loop is shut and close the valves with the key if you opened them.

Turn off the boiler, let rads cool down if they were not....not much chance in this weather, suppose?!

If you have a radiator key (can buy one for peanuts at any plumbers - get one you can fit on a keyring, easier to use), good opportunity to bleed air out of the radiators. Keep an old rag with you to catch the water. Only open bleed valves little at a time till air or water starts to come out. Stop when water starts to come out. If the pressure hasn't dropped to 1-1.5 after this bleed one radiator of water until it does.

Be careful not to open rad bleed valve too much or you'll get into trouble.

Good luck

 

[trinabob]

thanks for the help here! i feel like such a idiot i tell you!

I left the filling loop closed, with the line on the head of both the screws horizontal.

now if they are closed should water be running out of the copper pipe which goes out the wall to outside? water has been running out of it but me thinks me mother may have been fiddlin with it herself while ive not been here (can you tell we're a family of fiddlers and worriers!)

will have a go at bleeding the radiators tomorrow. we did bleed them a couple of weeks ago as they weren't getting warm in parts, so got rid of the air in them. they work fine now - so my fiddling isnt all bad!

so i guess i will bleed one of any air and then water till pressure drops. i should turn radiator key and let a little out at a time is that right?

 

[chrishutt]

Sounds like you've got the filling loop open. You check it by undoing the flexible connector between the two valves, but you'll get wet if they're not both shut. The slots should be at 90° to the direction of flow through the valve - not necessarily horizontal.

 

[trinabob]

yep right again. just bled the radiator as was making a very funny noise. pressure back at 1.2 now, and appears to be fine. will check in morning.

thanks for helping out, all good fun for a friday night eh!