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.

 

[ShaunCorbs]

It’s open vent open hence the little tank in the loft the red dial Valve as it was before if you have touched it

Can you hear the boiler start up ?

Any pictures of the set up ?

 

[lukeadams]

It’s open vent open hence the little tank in the loft the red dial Valve as it was before if you have touched it

shouldnt the boiler be able to re-pressurise itself in that case? cause its not, the valve is as it was. pressure remains low and its been like that since wednesday

 

[ShaunCorbs]

shouldnt the boiler be able to re-pressurise itself in that case? cause its not, the valve is as it was. pressure remains low and its been like that since wednesday

No won’t re fill if it’s via a filling loop but if it’s via the little tank in the loft yes will automatically fill

 

[lukeadams]

No won’t re fill if it’s via a filling loop but if it’s via the little tank in the loft yes will automatically fill

there is no filling loop anywhere in the house and its not refilling and there is a little tank in the attic

 

[ShaunCorbs]

Does it have water in the little tank ?

 

[lukeadams]

Does it have water in the little tank ?

I Havnt opened it to check as its covered with some form of padding which i didnt want to disturb, I guess its for insulation but its pretty cold to the touch so it seems like it may have cold water in it

 

[gmartine]

We don't think a lack of pressure is the problem, your boiler isn't a combination boiler so does not need to be pressurised even though it can be and why it still fires.


Can you add pictures of the system?

 

[lukeadams]

at the moment I cant add pictures, im trying to understand this system better. Last year we had the same issue, the pressure went low and the boiler stopped heating the rads and hot water and I managed to get the pressure up again (cant for the life of me remember how) and once that happened the boiler was working perfectly again and it has been up until wednesday. Our water was cut off on wednesday due to building works outside our house and thats when the issue started, the water has been back since Friday yet boiler is still out of action.

 

[lukeadams]

here's a few pictures though not sure if it will help much. there's a lot of junk in the airing cupboard preventing me from getting proper pics

 

[lukeadams]

I've also checked and the little tank in the attic has water in it, the valves in the pictures above are moving correctly when boiler is turned on, the exit pipe from the pump is hot and the pipe gets colder the further away from the pump i get (still hot, just not very hot) all the pipes in the hotpress are cold no matter how long the boiler runs for. the little white boxes on the valves are getting hot when running but not the pipes themselves. the pump isnt running hot itself. the boiler seems to just carry on as if everything is normal.

 

[ShaunCorbs]

Sealed gravity system so the little Tank in the loft is your ch water

 

[lukeadams]

Sealed gravity system so the little Tank in the loft is your ch water

i opened the red cap on top of the pressure gauge and it made a gurgling sound and it released water outside, then i put the boiler on and the upstairs radiators began heating up for about 15 mins and now its gone back to the way it was, no heat or hot water

 

[lukeadams]

Had a gas Engineer around earlier and he was here for hours checking it. he said that its 1 of 3 things faulty. The boiler itself its knackered (its pushing 10 Years), the Pump (Only replaced november just gone so its unlikely) or the diverter valve in the boiler itself. So now ive to wait on the council to make a decision on whether to repair it or replace it

 

[gmartine]

Mmmm....it's a heat only boiler so won't have a diverter valve nor should it take hours to have diagnosed that, if you can get a second or third opinion.

Edit: Post a pic of the boiler

 

[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.