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sean · Joined: 24 Oct 2007 Posts: 4 Location: luxembourg

Hi,

have 5 Heimeier radiators on the 3rd floor of the house. As only the valve side and bottom of the rad would heat up i decided to bleed them. I bled the first one and the air came out but was not followed by any water squirting out (the sign i was looking for to retighten the valve).

After bleeding the 1st one for about 15 seconds i retightened the valve and tested the rad's. Now none of the them have any heat coming out of them even though i only bled the 1 rad.

I only turned the rads off at the radiator and not down at the main CH point/boiler/whatever the building has, so this may be where things have gone wrong, although i reckon air pressure may have something to do with it as well.

any ideas?

Cheers
Sean

thescruff · Moderator Joined: 03 May 2003 Posts: 4632 Location: Bath

more info on the type of system required.

sean · Joined: 24 Oct 2007 Posts: 4 Location: luxembourg

Hi,

the main boiler is a Veissman, model Vitocell 100. Hopefully this is enough info as its the only thing i'm sure about.

reading on wikipedia, i'd guess it's closed water system, couldn't see or hear any pumps or fans in the basement so guessing again it works on water pressure. there was a barometer showing water pressure on this box next to the boiler with the gauge just below 1.

cheers
sean

thescruff · Moderator Joined: 03 May 2003 Posts: 4632 Location: Bath

Top the pressure up to 1.5-2bar and then try venting the rads.

You will need to repeat this several times to get all the air out.

Leave the pressure at 1.2bar.

sean · Joined: 24 Oct 2007 Posts: 4 Location: luxembourg

Hi,

not sure how to increase the water pressure, have turned two of the valve taps and although the pressure needle did drop a bit there was no increase. it reverted back to where it was after i turned the valve taps off again.

doesn't seem to be any control on the vitodens natural gas-fired wall-mounted condensing boiler (http://www.viessmann.us/web/canada/ca_publish.nsf/Content/Vitodens100_ca_english) that i can use to adjust the water pressure.

anything ideas on what i can turn/push to get an increase in pressure?

thanks

thescruff · Moderator Joined: 03 May 2003 Posts: 4632 Location: Bath

If you look on page 7 you will see a valve on the right marked BF, there is a thread which you screw a flexible hose too.

The hose should be visible and within reach.

HSP · Joined: 22 Jul 2007 Posts: 92 Location: london

vitodens 100 needs a filling loop - there should be a pipe where the cold water goes to the central heating via a 2 valves you need to find this and opent them both to the pressures mentioned above

also viessmann is a german company
why are you loking at the north american site?

sean · Joined: 24 Oct 2007 Posts: 4 Location: luxembourg

Excellent guys, thanks for the help, back in the warm now.

Was checking out the american site just out of habit, as expected the german site wouldn't be in english and can't speak any german myself.

cheers again.