Help please - Low pressure in gas boiler.

GASMANN

+1 for what gary71 said, if the source of the leak is not obvious (visible wet areas or coming from safety valve) id stick an autofiller on the system untill spring/summer cos you might have to go without heat for a few days to try and pinpoint it

Delta2113

gary71 wrote: »

Can't be ruled out, but the plumber wants to add one which he may not have offered if one is already fitted:D

Plumber wants to fit an automatic filling loop - it's a manual top up loop at present. I dont have a problem doing it manually and would feel more in control and maybe be able to figure if latest addition of leak sealer I would get is going to work for example.

Personally I find auto fillers offensive as they are often used to hide a leak and I wouldn't be a fan of leak sealers either, I'm a miserable sod:(

EmmaH

Thanks for your replies.

I am going to isolate the boiler tomorrow and see if it the pressure drops.

I suspected the coil in the cylinder myself, so I isolated the cylinder (I asked the plumber to put isolation valves on because I want to replace the cylinder in the near future). System was still leaking, so I guess its not the cylinder coil.

I'll let you know how I get on after isolation the boiler.

Thanks.

Delta2113

If I can live with say topping up the boiler every three months should I just live with the leak that I reckon I have rather than get the leak sealer put in. I last had leak sealer added back in October 2009. Probably a hard question i know but is the leak more likely to get worse if i dont get the leak sealer added or is it just as likely to stay the same and managable.

Delta2113

Delta2113 wrote: »

If I can live with say topping up the boiler every three months should I just live with the leak that I reckon I have rather than get the leak sealer put in. I last had leak sealer added back in October 2009. Probably a hard question i know but is the leak more likely to get worse if i dont get the leak sealer added or is it just as likely to stay the same and managable.

You may find the volume of water you are losing over 3 months is so small that it would make it very hard to find and would respond well to leak sealer, as posted I'm not a fan of leak sealer but it's better than a leaking system I suppose.

The problem you have with a system that needs topping up like yours is it can effect the quality of your heating system water which can encourage the devolvement of sludge shortening the lifetime of your boiler, if your system is clean it would be worth adding inhibitor to prevent sludge then maintaining the inhibitor level by topping it up every year.

The other issue is the lack of incoming pressure, if it were me I would be getting a clever plumber to come up with a way of filling your system so you can fill the boiler to 1 bar.

lpool2k05

Hi...same type of problem..

Today my boiler wouldnt go past 1 when usually its at 3...Has my gas being disconnected or is this a boiler problem..I never got any letters of disconnection but I do have an overdue bill

Thanks for any replies

Delta2113

Is it ok to live with a leak? If I'm happy enough to top up say ever 3 month's - should i just leave it alone or is the fact that i have a leak could this leak get worse with no treatment. If the leak sealer work's other than not having to top up so much are there any other benefits?

I'm against the plumber's idea of putting in an automatic top up loop but I just cant make my mind up about getting the leak sealer added or not to the system. Please scroll back to read my previous comments. I very much appreciate comments to date.

Delta2113

Delta2113 wrote: »

Is it ok to live with a leak? If I'm happy enough to top up say ever 3 month's

I would, untill I see evidence of where it's coming from or it gets worse.

Delta2113 wrote: »

I should i just leave it alone or is the fact that i have a leak could this leak get worse with no treatment.

All you can do is monitor it, it may never change or it could get worse, you'd soon know if it got worse.

Delta2113 wrote: »

IIf the leak sealer work's other than not having to top up so much are there any other benefits?

I don't like leak sealers for the impact they could have on a boiler and how they could effect system water but a lot of installers have used them with no ill effects.

Delta2113 wrote: »

II'm against the plumber's idea of putting in an automatic top up loop

Agreed:)

Delta2113 wrote: »

Ibut I just cant make my mind up about getting the leak sealer added or not to the system.

It would be more important to make sure your system water isn't getting dirty then add/maintain your inhibitor which will protect your system from the build up of sludge.

lpool2k05

lpool2k05 wrote: »

Today my boiler wouldnt go past 1 when usually its at 3...

do you mean on your pressure gauge Or the temperature gauge?

lpool2k05 wrote: »

Has my gas being disconnected or is this a boiler problem..I never got any letters of disconnection but I do have an overdue bill

you'll have to ring your supplier and ask.

Delta2113

If the leak sealer does actually work and as mentioned before I did have some added to my system back in Oct 2009 how long should it keep working for? Would it be for 5 years as I read somewhere?

Delta2113

Delta2113 wrote: »

If the leak sealer does actually work and as mentioned before I did have some added to my system back in Oct 2009 how long should it keep working for? Would it be for 5 years as I read somewhere?

I have no experience of a sealer working, all my experiences are with sealers that havn't worked, so I don't know:o

EmmaH

Hi Guys.

I just want to give some feedback on my problem.
I removed the cylinder and capped off the coil connections.

One of the isolations valves wasn't creating a perect seal.
Looks like there was also a leak in the cylinder coil.

Pressure is now ok. I just have to get a new cylinder now.
So, If there is a leak that you can't find, check the cylinder first before you rip your house up like I did.

DGOBS

To test the cylinder, one possible way would be drop the central heating pressure to zero, but dont empty the system (even .1bar will do) ensure the feed valve isnt passing, if a filling loop, remove it (as should be done anyway) monitor the system for 24-48 hours and see if the pressure increases, if so, it's possibly been feed from the cylinder coil, kind of the reverse of what Gary suggested to test the boiler for water loss.

On sealed systems, you could increase the pressure to 2-2.5bar, and closely look at the feed pipe in the storage tank, you may see some bubbles drifting up, but very hard to tell sometimes

slavetothegrind

on the low incoming mains issue do you have a shower pump?

If so a second filling loop off the pressurised side of the shower pump pipework would do the job for you

Delta2113

Pressure dropped from 0.8 to 0.6 on saturday and got red light on boiler so had to top up - so i got 7.5 week's. Again the pressure wont go up much so it's a guess how long i'll get this time. Is this an option - topping up every aprox 7 weeks?

Only other option is to try getting the leak sealer put in and I dont want the automatic filling loop added as was recommended by one plumber.

aujopimur

Regular topping up will cause corrosion in your heating system, try adding oxypix as a leak sealent.

Delta2113

Dublin City Council was out last week (i did not call them) on the footpath outside the house marking the path yellow. The mother went out to them and they said there was a leak and they would have to replace a pipe - Mother mentioned about water pressure being terrible and would this have anything to do with it and they said probably.

Hopefully when they come back and do the work in a few weeks or months -dont know when -this will bring back up the pressure. Any thoughts?

Delta2113

Dublin City Council back out on Tuesday - dug up footpath and replaced some piping - said their was a small leak outside and when the piping was put in 60 years ago or whatever the value was only opened half way which would explain why water pressure was always bad - oh well better late than never!

The good news i tried topping up today and the needle shot up - pressure is great - so glad i did not get auto filling loop put in. Now time to monitor the small leak which i still think i have within the central heating system. The men from the council did a good job.

Delta2113

I topped up again last night to 1 bar - it seemed to take longer this time. I then had the heating on - when I checked this morning it is back down 5 black marks below 1 bar. Should it be staying on exactly 1 bar or is this just the system adjusting itself properly and it will stay on the 5 black marks below 1 bar - hopefully you understand what i'm trying to say.

aujopimur

Did vent the air from the system and disconnect the filling device after repressurising, if you did, and it lost pressure overnight somthing is leaking.

Delta2113

aujopimur wrote: »

Did vent the air from the system and disconnect the filling device after repressurising, if you did, and it lost pressure overnight somthing is leaking.

- No I did not vent system - it's a manual filling loop in hot press - immersion switch is near it and i turned it back off again (manual black knob) after i topped up. It dropped for me the last time as well but it seem's to hold for a few month's. The pressure showing last night on the actual digital display on the boiler itself was 1.1bar - this is now 0.9bar. I dont dispute i have a leak but if it was big surely it would keep going down day after day.

aujopimur

It's normal for the pressure to fluctuate as the system heats/cools.

Delta2113

Had more trouble with pressure and got leak sealer put in - pressure seem's to be holding again. I also mentioned running noise of water near hot water cylinder to plumber and When i was out it seems he has re-connected an old pipe back to my old feed and expansion tank. I'm sure he disconnected that years ago when he actually put in the new boiler. Have i now a semi-sealed system? Do i still use my manual filling loop 1-2 times a year or will this new set up keep topping up the system?

shane0007

Delta2113 wrote: »

Had more trouble with pressure and got leak sealer put in - pressure seem's to be holding again. I also mentioned running noise of water near hot water cylinder to plumber and When i was out it seems he has re-connected an old pipe back to my old feed and expansion tank. I'm sure he disconnected that years ago when he actually put in the new boiler. Have i now a semi-sealed system? Do i still use my manual filling loop 1-2 times a year or will this new set up keep topping up the system?

Yes this will keep topping up your system and continuous feeding of fresh oxygenated water will eventually corrode your system from the inside out. But hey ho, at least you won't have to call him back to find the leak, well not until all your rads leak from rust and pin holes!

corkgsxr

shane0007 wrote: »

Yes this will keep topping up your system and continuous feeding of fresh oxygenated water will eventually corrode your system from the inside out. But hey ho, at least you won't have to call him back to find the leak, well not until all your rads leak from rust and pin holes!

mm auto fillers are only to make filling from empty faster. not to keep pressure up when you have a leak.

i also have doubts about most of the leak sealers. only one iv seen work is repa-r but its 70 euro a bottle. claims to be able to seal a leak of 200 litres a day. :eek:

Delta2113

Does the F & E tank act as a auto filler? I have a manual filling loop and this is turned off. The above two posts kinda disagree with each other with all due respect. Will my pressure still drop naturally as it should say every 6 months or so or as 0007 says it's constantly being topped up.
I appreciate your help guys.

shane0007

Delta2113 wrote: »

Does the F & E tank act as a auto filler? I have a manual filling loop and this is turned off. The above two posts kinda disagree with each other with all due respect. Will my pressure still drop naturally as it should say every 6 months or so or as 0007 says it's constantly being topped up.
I appreciate your help guys.

If you have a pressurised system and a f & e tank has been added, fed by a pipe with a non-return valve & left permanently open, firstly your pressure will decrease to the head of your system, i.e. 0.1 bar per metre of head height and secondly, if you have a leak within your system, it will automatically replace the water lost via the leak. The effects will be as I previously described.

An automatic filling valve, which is really a pressure reducing valve, when left permanently open and set to 1 bar pressure will allow mains water through the valve to replace the water lost via the leak, and the same effects will occur. The only difference is the pressure maintained within the system.

Delta2113

I got up in to the attic to try and figure out what he did. I have three pipes near my hot water cylinder. One pipe is hidden behind it running downwards so not sure exactly where it goes and it has a red handle to lock it off - another pipe with red handle has the manual filling loop which runs downwards but also branches off into the hot water cylinder. The last pipe runs upwards and into the top of the water cylinder and this is the pipe that he re-connected back up into the attic. Also another pipe comes upwards from downstairs and goes into the bottom of the hot water cylinder and has a red handle.

I got up into the attic - one pipe runs across the attic and i cant see where it goes, another pipe goes into the bottom of my large water tank on one side and another pipe comes out of this and goes off somewhere else. The third which he re-connected runs over to the F & E tank and has a pipe sitting over the tank. The tank is bone dry and where there was a what i would presume a water pipe connected at the bottom this is still capped. So is he just using the vent feature?

Hot water cylinder is in my bedroom.

Delta2113

Delta2113 wrote: »

I got up in to the attic to try and figure out what he did. I have three pipes near my hot water cylinder. One pipe is hidden behind it running downwards so not sure exactly where it goes and it has a red handle to lock it off - another pipe with red handle has the manual filling loop which runs downwards but also branches off into the hot water cylinder. The last pipe runs upwards and into the top of the water cylinder and this is the pipe that he re-connected back up into the attic. Also another pipe comes upwards from downstairs and goes into the bottom of the hot water cylinder and has a red handle.

I got up into the attic - one pipe runs across the attic and i cant see where it goes, another pipe goes into the bottom of my large water tank on one side and another pipe comes out of this and goes off somewhere else. The third which he re-connected runs over to the F & E tank and has a pipe sitting over the tank. The tank is bone dry and where there was a what i would presume a water pipe connected at the bottom this is still capped. So is he just using the vent feature?

Hot water cylinder is in my bedroom.

Anybody figure this out please?