air trapped in coil

[mutley racers]

Been called out to this job today. Boiler locking out in hot water mode. Flow was roasting and return cold. So moved pump between 3-2 to get rid of it, it worked but it is still getting pushed around hot water circuit. You can hear it in the coil, sounds like the water is boiling in cylinder. Also mad gushing noises coming from this circut. It has a air vent on the horizontal flow to cylinder but it is one that is actually incorporated into a 22mm t. So it's flat and you open it with a flat head. No blockageson any pipework. Vent not sucking in water. Strggling to get air out of system in hot water only.

What's the crack guys?

 

[Linkyplumb]

Have you got all the air out through the air valve?

 

[mutley racers]

i got as much air out as i possibly be could. it is in the centre of the pipe closest to us in picture. Do you think it would be better to put an auto air vent close to where flow enters the coil

 

[Linkyplumb]

Yeah maybe put another av nearer the coil and a bit higher

 

[mutley racers]

is it worth putting one on the return also or just the flow. As I have never heard anything like this before. It is pretty radical amounts of air

 

[mutley racers]

here it is[video=youtube_share;di9Dr4Jjprg]http://youtu.be/di9Dr4Jjprg[/video]

 

[glenno1]

Is it back boiler or wall hung

 

[mutley racers]

it is a wall hung boiler. Boiler is about 500mm below cylinder

 

[diamondgas]

Where's the feed and vent? F&E tank got water in it? does the 'noise' go away when the heating is turned on mutley races?

 

[mutley racers]

Where's the feed and vent? F&E tank got water in it? does the 'noise' go away when the heating is turned on mutley races?

Hi Diamond, if you see the picture I put up and look to the 22mm pipe on the right going p the wall, that is the feed and vent. You can see the feed tee into the vent just above the shelf. And yes, indeed tthe noise does go away when it is on just heating and heating and hot water

 

[diamondgas]

Hi Diamond, if you see the picture I put up and look to the 22mm pipe on the right going p the wall, that is the feed and vent. You can see the feed tee into the vent just above the shelf. And yes, indeed tthe noise does go away when it is on just heating and heating and hot water

Sounds more like a blockage/restriction in the hot water circuit, first thoughts? I'm guessing the boiler in question is a low water content/modernish boiler yeh? Is there any kind of 'balancing' valve fitted to the hot water return? Was the combining of the f&e above the shelf, by any chance, something done at a 'later date' do you think? Just wondering if the issue is a past problem rearing it's head once more ?

 

[SafeGasInstall]

cold feed tee to vent and there is compression fitting , drain down and see for your self

 

[mutley racers]

no blockage in cold feed into vent. Checked it. water flows freely. It is a potterton boiler, about 10yrs old. the one that has the side panel to get to circuit board and gas valve. The plumbing has not been changed since they put the boiler in 10yrs ago

 

[diamondgas]

no blockage in cold feed into vent. Checked it. water flows freely. It is a potterton boiler, about 10yrs old. the one that has the side panel to get to circuit board and gas valve. The plumbing has not been changed since they put the boiler in 10yrs ago

A suprima? If so does it go to lockout/o-heat? If you have combined f&v air isn't usually a problem providing the feed is clear, as mentioned. The noise can be more due to the boiler overheating producing 'steam' pockets... If that make sense? Still sounds like a restricted flow through the coil/water circuit. IMO! Especially if it isn't there when the heating or "both" are on together! If it's just occurring on hot water then I'd be more inclined to investigate flow through the hot water circuit!! There's also a boiler issue to consider if it's a Suprima'; I've known of an issue regards the pump overrun failing, cutting the pump off when the water flow temp gets to a certain temp?

 

[mutley racers]

yes a suprima. it was over heating and going to lock out. but it is not any more.

 

[mutley racers]

A suprima? If so does it go to lockout/o-heat? If you have combined f&v air isn't usually a problem providing the feed is clear, as mentioned. The noise can be more due to the boiler overheating producing 'steam' pockets... If that make sense? Still sounds like a restricted flow through the coil/water circuit. IMO! Especially if it isn't there when the heating or "both" are on together! If it's just occurring on hot water then I'd be more inclined to investigate flow through the hot water circuit!! There's also a boiler issue to consider if it's a Suprima'; I've known of an issue regards the pump overrun failing, cutting the pump off when the water flow temp gets to a certain temp?

ah ha diamond, i forgot about that, the pump would all o a sudden just stop and instantly start again.

 

[diamondgas]

ah ha diamond, i forgot about that, the pump would all o a sudden just stop and instantly start again.

Sounds like it might be linked to the boiler overrun rather than a system problem ... Alas that's incorporated in the main PCB mate!

Will get this moved to GSR only mutley racers .. we're getting a bit technical for an open forum yeh?

 

[mutley racers]

ok yes, thanks diamond. was not expecting it leading to a boiler fault.

 

[diamondgas]

ok yes, thanks diamond. was not expecting it leading to a boiler fault.

still wouldn't rule out a circulation problem but if the custard starts talking about random o'heat, otherwise no problems with the hot water then I'd be more inclined to be looking at the boiler overrun..?

 

[mutley racers]

has this been moved to private forum then? Is it a new pcb needed

 

[diamondgas]

Yep we're moved ... and yes the relay in the PCB gets 'dirty', works some times and doesn't other times ... there's a website Ignite Heating Spares UK, - refurbished parts for domestic heating systems and boilers worth pointing the custard towards! They supply refurbished with 12 months guarantee! Well worth it IMO

 

[SafeGasInstall]

i have had few where ap is sticking

 

[mutley racers]

Yep we're moved ... and yes the relay in the PCB gets 'dirty', works some times and doesn't other times ... there's a website Ignite Heating Spares UK, - refurbished parts for domestic heating systems and boilers worth pointing the custard towards! They supply refurbished with 12 months guarantee! Well worth it IMO

Do you mean get the custard to replace it himself? But why would this cause the air issue? Because pump only stops for around 2 seconds and then starts again. Do you think the water gets so hot in that period and turns to steam? I thought about the steam part but when I checked vent, couldn't feel any spurt out. The client also said that the pump has been coming on at random times in early hrs. Could this also be a symptom

 

[diamondgas]

Do you mean get the custard to replace it himself? But why would this cause the air issue? Because pump only stops for around 2 seconds and then starts again. Do you think the water gets so hot in that period and turns to steam? I thought about the steam part but when I checked vent, couldn't feel any spurt out. The client also said that the pump has been coming on at random times in early hrs. Could this also be a symptom

I've had a cupl of customers order the pcb's online for various faults .. one being a pump overrun issue. It saves waiting in for the delvvery and any potential warranty problems being pointed your way..... And NO, custard orders and you fit

Regards the fault. If I suspected the overrun I'd want to be checking the system from cold! Put into water only and fire up. Hands on flow and return to check how well the system was circulating. If no serious temp diff then I'd continue to run on hot water only to get the boiler up to max temp ASAP. If overrun issue is what you're testing for then you need to be either checking the pump or have your multimeter on the pump live&Neutral at the terminal strip on the boiler. there needs to be a constant 230v. If the noise starts in conjunction with the power dropping out then you know the overrun relay on the pcb is gooshed!!! Thing is with intermittent faults it's not guaranteed to happen all the time!!!

Check it from cold mutley racers ... f&r temp diff on h/w only will tell you how well the boiler is circulating from start-up till fail...!

 

[hammers4spanner]

Pcb issue had a couple like this last year on contract where it was a potterton utterly horrific pcb issues .