Heating system problem

Lucutus

Some background:

At the start of November the system had a power flush, new grant vortex boiler and a new pump installed.

After that work was completed, the system worked great, all rads warm.

However it was constantly 'bubbling' like there was air in it. We were advised by installer that it was just running new fresh water through and it would stop, which it never quite did.

About 3 weeks ago, an oil delivery timing mistake meant that the boiler ran dry and locked. Contacted the installer who advised us to turn the airlock and away it went again.

It didn't settle back properly with air bubbling in the system again and within a day or two water in the house, (except for the kitchen tap), was running yellow turning to brown after a few days.

With the installers' guidance, we were able to diagnose that the heating supply tank overflow was going into the cold water storage tank, the heating supply tank, (situated above the CWST), was full of dank water and rusty sediment which had overflowed into the main tank and then the hot water cylinder.

To clear the water, we emptied the tanks in the attic with buckets and cleaned the main water tank, then we adjusted the ballcock of the heating supply tank so it can't overflow anymore, refilled the tanks and restarted the system.

Now, every time the heating comes on, it is bubbling away immediately and we have to bleed each rad to get any heat out of them, usually 2 or 3 will come on but not always the same ones and not always fully.

Installer has recommended re-piping the system or pressuring it, but due to the cost implications and the recent spend on the previous works, either one is not an option for us in the immediate future.

We're hoping we can somehow get the system back to the way it was working before and immediately after the new boiler was installed.

Any suggestions would be very welcome, bleeding radiators twice or three times a day is not an ideal situation!

TL;DR: To get the heating working, We have to bleed rads, 3 or 4 of them, each time we turn on the system. We can hear air moving through it when it comes on, it doesn't stop, but eases after bleeding the rads. Need help!

K.Flyer

Did you ever have these type of problems before the new boiler went in?

Lucutus

No, never had a problem like this before. Learning more than I ever thought I could know about plumbing and heating this year

Dtp1979

Lucutus wrote: »

No, never had a problem like this before. Learning more than I ever thought I could know about plumbing and heating this year

Did he alter any pipework whilst doing the new boiler? Did he switch the pump from return to the flow? Bleeding the rads every time is going to internally corrode every piece of steel on your heating system. I.e your rads and boiler

Lucutus

No work to internal pipework, He replaced the pump in-situ.

Bled the boiler a while ago too, no air from that.

Have noticed in the last few minutes that the pipe coming from the base of the heating tank in the attic is hot and water inside the tank is also hot. The level has risen more than the ballcock should allow, it's submerged under the water there now.

Not sure if that's relevant, but it doesn't seem right at all to me?

Dtp1979

Lucutus wrote: »

No work to internal pipework, He replaced the pump in-situ.

Bled the boiler a while ago too, no air from that.

Have noticed in the last few minutes that the pipe coming from the base of the heating tank in the attic is hot and water inside the tank is also hot. The level has risen more than the ballcock should allow, it's submerged under the water there now.

Not sure if that's relevant, but it doesn't seem right at all to me?

Take some pics especially of the hot press

esox28

Blank off the vent going from heating to the small header tank, you could use a safety valve if you wished.
Note..so long as you have no solid fuel and no non return valve on the feed pipe.
You will need to ensure the feed pipe usually half inch valve is never shut off when boiler is running.

Lucutus

Dtp1979 wrote: »

Take some pics especially of the hot press

Here some pics. I took one of the F&E tank also, the water level has come down again, now that the heating is off, but you can see where it was upto last night when the ballcock was submerged.

esox28 wrote: »

Blank off the vent going from heating to the small header tank, you could use a safety valve if you wished.
Note..so long as you have no solid fuel and no non return valve on the feed pipe.
You will need to ensure the feed pipe usually half inch valve is never shut off when boiler is running.

Forgive my limited knowledge, the vent, that's the pipe hanging over the F&E tank? Unfortunately, I've no safety valve lying around...my plumbers toolkit only contains a hammer, radiator bleed key and a vice grips. I haven't noticed any air suction on that pipe when the system is running. It appears the F&E tank is filling from the pipe at the bottom of the tank, (Not the mains feed with ballcock).

esox28

yea thats the pipe hanging over the fande tank just get a push on blank as i suspect with the tank getting hot yuo are circulating water around the tank just a quick stop gap is to blank the vent or you could turn off the half inch valve closest to the door of hotpress either option will stop tank getting hot but turning off the feed pipe could lead to water shortage in the system. any ways you will need to get a desent plumber to rectify asap.

be carefull that fande tank look like it could fall into the water storage cistern:eek:

Lucutus

I've spent some time up there watching it and haven't seen anything coming out the vent pipe or any suction on it either, checked for that last night.

I know we'll need to have the pipework overhauled and the heating plumbing pressurized, along with an independent overflow directly to outside the house done, but it'll be the end of January before I have anything near the funds for all or part of that.

If memory serves, I removed a length of timber from that side of the F&E tank so I could get better access to it to remove the ballcock, looking at the picture, now I know what it was for! Might just put that back now...

Billy Bunting

That is an absolute shocking mess, how any plumber worth is salt could leave it like that is criminal.

It sounds (if i'm understanding correctly)to me like you may have a split coil on the cylinder, also IF the system was powerflushed there should have been a chemical inhibitor added, that has certainly been leaking into the domestic storage tank, you really need a pro in to look at this.

esox28

Billy Bunting wrote: »

That is an absolute shocking mess, how any plumber worth is salt could leave it like that is criminal.

It sounds (if i'm understanding correctly)to me like you may have a split coil on the cylinder, also IF the system was powerflushed there should have been a chemical inhibitor added, that has certainly been leaking into the domestic storage tank, you really need a pro in to look at this.

yea thats what i first taught but i think op mentions the fande tank was over flowing into the storage cistern.

look like the feed is teed into the suction side of the pump maybe.

was there a powerflushing machine used or another method?

Lucutus

Billy Bunting wrote: »

That is an absolute shocking mess, how any plumber worth is salt could leave it like that is criminal.

It sounds (if i'm understanding correctly)to me like you may have a split coil on the cylinder, also IF the system was powerflushed there should have been a chemical inhibitor added, that has certainly been leaking into the domestic storage tank, you really need a pro in to look at this.

I have been keeping an eye on it to try to make sure that it won't overflow again, I spent too much time cramped up in the attic to empty and clean that CWST to get fernox out of the water that kids were taking baths in.

I do know it needs the overhaul, see above, money talks here.

esox28 wrote: »

yea thats what i first taught but i think op mentions the fande tank was over flowing into the storage cistern.

look like the feed is teed into the suction side of the pump maybe.

was there a powerflushing machine used or another method?

I was at work when it was done, but I understand it was a powerflushing machine and some banging on pipes to try to get the sludge out of it, it was very badly gunged up.

I took some pictures of the back of the pump to try to find the direction and traced some pipes. The flow/direction of the pump seems to be going towards the boiler alright.

I think the reason I'm getting hot water in the tank and it is filling up past the ballcock level/close to overflow is that the feed pipe is connected at a T just to the left of the pump. The pump must be pushing the hot water up and into the tank.



I also found the control on the pump and turned it down from #2 setting to #1 to see if that helps.

esox28

Yea that's the feed pipe I was referring too. Has to be pumping up that to the fande maybe not circulating so if you turn off the wheel valve for the moment with the view to installing a no return valve or pipe reconfiguration as soon as.

Dtp1979

That's the expansion pipe from the system. I'd never turn that off or put any valve on it unless an expansion vessel was fitted

esox28

op would still have the vent pipe.

Dtp1979

esox28 wrote: »

op would still have the vent pipe.

Agree but what'd happen if the vent is pitching? How is the water going to be replaced into the system if the valve is closed on the expansion?
But I know what ya mean esox, it'd be a temporary solution but sometimes temporary solutions are forgotten to be fixed and the system is left like that

esox28

Yea I know, but op said earlier that he watched the expansion as system was running and no circulation through the vent pipe, so it looks like the cir pump is putting positive pressure on feed pipe and pushing ch water back up to the fande tank, overflowing it to a point where the tank overflows into cw cistern. Not good as system probably been dosed with mb-1 or similar.

Dtp1979

esox28 wrote: »

Yea I know, but op said earlier that he watched the expansion as system was running and no circulation through the vent pipe, so it looks like the cir pump is putting positive pressure on feed pipe and pushing ch water back up to the fande tank, overflowing it to a point where the tank overflows into cw cistern. Not good as system probably been dosed with mb-1 or similar.

With a system that bad god knows what'll happen if the expansion Is blocked

esox28

Once one of either the vent or feed pipe is open there wouldent be any issue.

Lucutus

Thank you both for your input, I can see the sense in both arguments there, there's pros and cons with any temporary workaround approach, but needs must.

Continuing to bleed the rads a few times daily is going to drive us crazy up in here and as mentioned earlier in the thread, corrode radiators and the shiny new boiler :eek:

So, with that in mind and seeking opinions, here's what I'm planning to do:

• Tie up the ballcock and drain the F&E tank
• Clean it out, (might as well while it's empty)
• Close the wheel gate valve on the feed in the hot press
• Cut the feed pipe a few inches over the now closed wheel gate valve
• Remove a section of copper pipe to a position level with the vent pipe over the hot water cylinder
• Fit a lever valve to the feed pipe
• Extend slightly and fit a pushfit elbow joint
• Use a section of the copper pipe to connect this with a new pushfit tee in the vent pipe.
• Cap off above the old closed wheel valve with a pushfit end, just in case.
  
• Unrelated to above...replace a seized up radiator lock shield valve while I'm at it, (hot pipe to rad, but the rad doesn't heat or bleed air, very old valve in place, I cant get a turn on it to open properly)

The thinking here is that the pump can no longer push the water back up the existing feed pipe to f&e tank and the the system is provided fresh water down the vent pipe and can expand up the same pipe to pitch if required.

The new vent/feed pipe connects elsewhere to feed the system not directly after the pump in the direction of flow as the current feed pipe does.

Are there any downsides I might be missing here?

In other news there's been a definite improvement since I reduced the pump speed to #1 from #2, I don't have to bleed for half as long per rad now.

Lucutus

Quick update to my plumbing woes...

I went to have a go at the above bits yesterday and I found I couldn't drain the whole system through the drain valve because it's calcified shut, so I can't do the pipework.

I drained what I could through the radiator in the kids room so I could replace the stuck valve on it... in an effort to get that rad working again... took me about 2 hours and a trip to Woodies to get a €5 radiator hex key to remove the old adapter, but I eventually got it done.

After all that, the rad is barely heating, is it possible that they just need to be balanced or perhaps something else is at play?