Question about Worcester Bosch Boiler

[JayPJay]

Any plumbers give us a bit of advice, The pressure gauge on our combination boiler has gone below one bar, how do we add cold water to the system as it says in the manual, The plumber who fitted it didnt give us any instructions how to do this. Thanks

[Newton's Ring]

Beneath the bottom of the boiler there should be a slide out flap. There are a few methods for introducing more water to a closed system such as this. On my WB boiler, on this slide out plastic flap, there is a small key type thing. Remove this from the flap.

Beneath the boiler itself there is a small black orifice which is shaped the same as the key end. Push the plastic key up and turn it . There should be a small white plastic (50p shaped thing) next to it - undo this slightly as if undoing a tap and you should hear water being introduced to the system. If water comes out you haven't turned the plastic key properly - try again (I think it might be lefty loosy).

Once water is coming into the system you should see the pressure increasing. I normally stop when it's at about 1.5. Tighten the white plastic thing and turn the plastic key and remove the key (a small amount of water may drop down.

If you don't have a plastic key you may have a flexi pipe - -these are even more simple... there should be a isolating valve incorporated within the pipe. Open the valve - if it's plastic by turning it - if it's metal by using a screwdriver to turn the | to - keep an eye on the pressure gauge and close the valve when required.

Hope this helps but it's thursday night and the w/e has already started for me. hic

[JayPJay]

Thanks for that info it is the flexi hose with a tap at each end.which do we open first,

[Newton's Ring]

I am a little ****** but I'm pretty sure it's both. Shouldn't really matter as, when you think about it, it's on the same pipe.
Open one side first, you may not notice anything - then open the other slowly and you should hear it filling.

[JayPJay]

Thanks will give it a try in the morning

[Newton's Ring]

No probs. Good luck.

[sdb123]

Originally Posted by Newton's Ring

I am a little ****** but I'm pretty sure it's both. Shouldn't really matter as, when you think about it, it's on the same pipe.
Open one side first, you may not notice anything - then open the other slowly and you should hear it filling.

It's both on my boiler.

[CaptainCook]

Originally Posted by Newton's Ring

Beneath the bottom of the boiler there should be a slide out flap. There are a few methods for introducing more water to a closed system such as this. On my WB boiler, on this slide out plastic flap, there is a small key type thing. Remove this from the flap.

Beneath the boiler itself there is a small black orifice which is shaped the same as the key end. Push the plastic key up and turn it . There should be a small white plastic (50p shaped thing) next to it - undo this slightly as if undoing a tap and you should hear water being introduced to the system. If water comes out you haven't turned the plastic key properly - try again (I think it might be lefty loosy).

Once water is coming into the system you should see the pressure increasing. I normally stop when it's at about 1.5. Tighten the white plastic thing and turn the plastic key and remove the key (a small amount of water may drop down.

If you don't have a plastic key you may have a flexi pipe - -these are even more simple... there should be a isolating valve incorporated within the pipe. Open the valve - if it's plastic by turning it - if it's metal by using a screwdriver to turn the | to - keep an eye on the pressure gauge and close the valve when required.

Hope this helps but it's thursday night and the w/e has already started for me. hic

On my Bosch (32CDi) the off pressure has always been 1.0 bar and when the boiler fires up the pressure increases to 1.5.

I'm worried that mine might be set too low. The water flow rate seems fine and it's hot enough to grow bananas in our sitting room, but just wondered why you set at 1.5 and not 1.0. Does it make any difference?

[Newton's Ring]

I only set it around 1.5 because it's around the middle of the green zone on the pressure indicator. Like you say, the pressure does rise about 0.5 bar when it heats up but it's still within the green zone.

For me, the rads feel a bit hotter than if the pressure falls below 1bar.

[neilios]

The pressure gauge has nothing to do with the operating temp of the boiler or the temp of the rads .The gauge should be a around 1-1.5 bar allowing around .5 bar for expansion .Those key filling loops on the WB are rubbish .

[vnb]

Guys , if it helps the user instructions for their modern boilers are available to download.

Gas boiler literature - Worcester, Bosch Group UK homeowner site

I have just had one fitted and couldn't find the instructions either.

[Kevstir]

when we had our WB boiler installed they put in a filling loop with a tap ether side, the guy said to open the feed tap first then turn the tap at the boiler side, the reason being was that it stops water flowing out of the heating system and contaminating the water supply, kind of makes sense but i don't think it would happen if the taps were opened the other was about due to the water pressure being higher that the heating system pressure.

I'm no plumber and just repeating what the installer told be.

[neilios]

Originally Posted by Kevstir

when we had our WB boiler installed they put in a filling loop with a tap ether side, the guy said to open the feed tap first then turn the tap at the boiler side, the reason being was that it stops water flowing out of the heating system and contaminating the water supply, kind of makes sense but i don't think it would happen if the taps were opened the other was about due to the water pressure being higher that the heating system pressure.

I'm no plumber and just repeating what the installer told be.

It doesn't matter really one of the valves should be a double check valve which prevents the backflow and water contamination.

[JayPJay]

Thanks for all the advise, have done as recommended and now the pressure is fine, also took air out of radiators and seems great now.

[Saggy]

i got a 37cdi boiler and i run it at 1.5 bar. i dont have a filling loop though but the filling is done on the boiler itself. what I would like to know is what the numbers on digital display of the boiler mean as they change alot.

Martin