Greenstar Ri No filling loop

[lukeadams]

Hi Everyone, hopeing someone can help

We have a Greenstar Ri Boiler and its lost pressure, pressure gauge on top of the boiler reads 0.6 bar and i know this should be around 1.5bar, there is no external filling loop near the boiler or in the hotpress, there is a pipe in the hotpress with a red dial on it labelled 'CF Heating' but when turned it doesnt do anything. In the attic there is the main water tank and a smaller tank above it with two pipes going into it. I have no idea how to re-pressurise the system and we have no heating or hot water. the boiler continues to run as if everything is normal but none of the radiators are heating and the hot water is coming out freezing no matter how long the boiler runs for. Also in the hotpress is the old immersion tank that we never use as its never worked since the day we moved in and there is a small red expansion vessel above the immersion tank.

none of the three red dials in the hotpress are able to fill the boiler.

Can anyone offer some advice please.

 

[John.g]

You may have a semi sealed system with a non return valve in the cold feed from the small tank to the boiler. You will the
N have a external e xpansion vessel where the pressure will still only be 0.5/ 0.6 bar with a cold system but greater than 1 bar when hot, locate this NRV and remove to clean/renew or give it a whack of a hammer.

 

[John.g]

You can see I think that NRV in the 3rd photo below the red wheel gate valve, first ensure this manual valve fully opened 3 or 4 turns between closed/openthengive the NRV a few whacks, otherwise isolate and clean renew check for blockage is cold water line.

 

[John.g]

Should have said, in 4th photo.

 

[cjg]

So now ive to wait on the council to make a decision on whether to repair it or replace it

so its acouncil house rented ? there for you should have called them out in the first place as its they problem!!!!!!

 

[gmartine]

Didn't read/see that, oh well UKPlumbs is an open house.

 

[cjg]

Didn't read/see that, oh well UKPlumbs is an open house.

thats why i alllways ask do you own the house or rent, as if its rented you have to ask premission to do work on it,
as i know some one did work on one and then big do. (it was ok before you started) you make it right at your expence

 

[John.g]

Strange how the gas engineer though couldn't figure out if it's a (semi) sealed gravity system or not and suggest a fix, these systems are very popular around here and appear to work quite well.

 

[gmartine]

Strange how the gas engineer though couldn't figure out if it's a (semi) sealed gravity system or not and suggest a fix, these systems are very popular around here and appear to work quite well.

Not seen many but what's the point of them as the system still basically operates at atmospheric pressure and allows oxygen ingress?

 

[John.g]

A lot more forgiving than the full pressurised system as the max pressure even when hot can be < 1bar, often used to cure pumping over in gravity systems due to circ pump change etc although systems like my combined vent and cold feed cures 99% of problems, oxygen ingress has never been a problem with some of my rads over 40 years old with only the odd drop of inhibitor added over the years. Several Plumbing aquantinces tell me they see more corrosionproblems with pressurised system especially the ones with auto top up.

 

[gmartine]

That all sounds quite plausible but you'd expect auto-top up systems to have corrosion issues if the additive concentrations were allowed to decrease. That's a basic maintencance rather than a system design issue, sealed or pressurised systems still have an efficiency advantage.

 

[lukeadams]

hi all so I have an update, another engineer appointed by the council visited yesterday, I wasnt in when he arrived but he apperantly fixed the boiler Not sure exactly what he did but the radiators were still warm when i got in from work however another issue has arisen since he left.... the feed to the cold water tank seems to have an airlock in it, tank is empty and water is dripping into it, the mains supply is fine in the kitchen sink. Not sure how to fix an air lock in the feed to the attic tank. Google only has results when its the taps that have the airlock and not the feed to the tank. Anyone have any suggestions on what possibly could have happened and how to fix... i realise without knowing what he did its not much to go on

 

[ShaunCorbs]

Call them back out

 

[John.g]

Throw a gall or so of water into the tank until its sorted out, this tank should never need topping up once filled.

 

[Ben-gee]

Is the ball valve stuck up in the air?

If so push it gently down and it should start refilling.

 

[lukeadams]

issue still ongoing, appeantly the boiler has a very slow leak in the syphon/trap. also the main tank in the attic isnt filling so once it empties we've no water at all upstairs. Apperantly the engineer had to order the part from the UK and we are currently expecting him to arrive today with the part to fit it not holding my breath though. Cant for the life of me understand why he is opting to replace a part in a 10 year old boiler rather than recommending to the council that its replaced. Boiler was commisioned into service on 29/03/2012.