Help please - Low pressure in gas boiler.

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?

jimjimt

It would seem that your small tank f+e was blanked off and your heating system pressurized.

What issues are you having ?

Can you forward pictures ?

Delta2113

Sorry cant supply pictures for now. The main issue has been pressure dropping and years ago leak sealer was put in but again recently pressure problem again. I had floorboards taken up to try and find a leak and had to get a new expansion vessel for the boiler. The leak was not found so far but plumber put in more leak sealer and it seems to be fine for now.

He has also suggested a magnet which can be fitted as far as I know for sludge - €400 - not sure about this as the rads work fine and hot all over. System is old.