Bleeding frustration

[DIYedboy]

There are times in one's life when ya think if only this whole posessed house would collapse on top of me right now at least I would be spared from this ongoing pergatory!

Having renewed,repiped and refilled my uncle's CH system, all that is left is refilling the sucker.........................simples!............................but not for me!

I have to fill from the top cos there's no outside tap to attach to a drain so I can fill from the bottom. I have tried this now about a dozen times with the same result, air in the pipes that refuses to enter a rad n sit at the top awaitng a 'bleed'. I have tried partially draining n refilling.........just the same, I can hear the air in the return as it drops back down to the backboiler.....................somebody save me!

 

[kevplumb]

what did you do to it any motorised valves etc

 

[DIYedboy]

Yes, one on the CH circuit (2 port), which I pull open when refilling

 

[kevplumb]

have you tryed running the system to see if it pushes it out

 

[DIYedboy]

many, many times, regularly the air descends to the boiler n the thing then locks out...........................I'm a broken man Kev!

What about if I add a horizontal run in the 22mmreturn with a vertical upstand and an auto bleed valve on top of it?

 

[kevplumb]

could do

but thats treating the effect not the cause

worth a go

another way is to connect mains to the cold feed at the tank

ie ballvalve to outlet with a hose has been known to work


there is another way but not yet

 

[DIYedboy]

The ballvalve don't have a stopcock so can't turn off, everything in the loft hasn't been touched for 40yrs............I'm frightened Kev

The thought of making a 3foot horizontal run etc etc seems the least way I could find myself out of my depth.

On the assumption that once the air is all out it can't return (possibly a foolhardy assumption)is this 3 foot run capable of releasing all the air in a few minutes or will it be a slow release over a few days?

 

[gas_man_gaz]

isn't it a open vented system? how come ya have to back fill it?
what i norm do is turn all the rads off except the one closest the pump 2 force the air through, keep stoping and starting and keep bleedin the rad until its cleared.. ya sure its airlocked and ya havnt got a blockage or a closed valve?

 

[DIYedboy]

Yes, open vented

I can hear the air moving round the 22mm pipes when the system is on, when it stops somewhere, something stops working ie a rad, then at other times it'll be the boiler (it'll lock out in 30 secs).

If I fill it from the ground up, the air naturally gets pushed up n out the vent..........no airlocks!

All valves open, no blocks I think.

 

[DIYedboy]

Is that it then? surely I haven't got all you experts out there stumped?

 

[bathstyle]

polished off too much wine to read the thread properly but............... blocked cold feed, or partial blocked??

 

[DIYedboy]

Yeah, that's possible cos the exp tank was very sludged up n I had to clean it out. How does this cause air in the system?

 

[twgas]

A blocked cold feed doesn't cause air in the system, draining it does. A blockage prevents it filling properly, cut out the pipe where the cold feed joins the system and you'll almost certainly find the problem.

 

[DIYedboy]

That end of the pipe has been replaced,(about 8 inches) but I haven't replaced the pipe from the tank down to the replacement piece

 

[doitall]

Unless you can drain the lower level you are always going to have air trapped.

Try turning the all flow valves off on the radiators and bleed through the return pipe.