Low heating pressure on Ferolli boiler

[Galahad]

Hi there... i moved into a flat earlier in the year which has a Ferolli gas combi boiler (not sure of model or age - probably >5 yrs). Hot water fine but have a few issues with CH (now its winter), and hoping someone can give advice: 1) The pressure when boiler cold is generally <1 bar (now 0.8!) Rises just above 1 bar when in use. 2) Certain rads seem to fluctuate between hot and warm, even though room temp remains cool and rad stats all on high setting. Seems like not all rads in flat can be piping hot at same time. Temp on boiler gauge about 22'C when CH temp set at max.
Can someone tell me how to increase the pressure and if this could improve heating. Would apprciate any advice!!

 

[ChrisR]

Can someone tell me how to increase the pressure

Do search on Filling Loop

Do you have thermostatic rad valves?

Bleed rads then refill system to about 1 bar..

 

[Galahad]

Thanks for response ChrisR. I'm not too knowledgable about this and won't pretend i am. All rads have Honeywell thermostatic valves on, which are at max setting (5). I'm confident about bleeding them, but not so sure on how to re-fill to correct pressure. Will look into it before deciding if it something i can do myself.

 

[Galahad]

Further to my last posts.. i've just turned on the heating and checked pressure and rad temperatures, and discovered i may have been a bit hasty in my original message! All radiators piping hot when first turned on, so imagine the fluctating rad temps is due to the boiler stat switching on and off.

I will bleed and fill/re-pressurize system when cooled down, so sits at 1 bar when cold.

Can anyone please advise what the temperature on the combined temp/pressure gauge is. As previously stated this is currently 22'C when boiler CH stat set to maximum.

 

[JonB]

Ferroli have a very good web site where you can doanload Manuals


www.ferroli.co.uk

JonB[/url]

 

[Galahad]

JonB... not sure what model i have as no identifcation on boiler, but site looks good so should be able to find right manual. Thanks.