Air in system after new boiler

[jeff the gasman]

Does your thanks button not work?

 

[DaveHerns]

Why does combining these solve the problem? Water circulation preventing build up ? I ask as I have a similar problem.

 

[Kev123456]

Thanks, hope to have a go at it the weekend

 

[Agile]

It is disappointing that the installer's flushing did not remove that sludge buildup. But that would depend on what chemicals he used.

Nor that he did not do a magnet test at that point as it is a very common problem.

The sludge at the connection with the feed point can contain a lot of lime compounds and be particularly hard. Not very easily dissolved either with the chemicals normally considered fairly safe to use on a heating system.

Tony

 

[jeff the gasman]

Why does combining these solve the problem? Water circulation preventing build up ? I ask as I have a similar problem.

Expansion and contraction keep the water moving, all day every day. As opposed to dedicated feed and expansion.

 

[jeff the gasman]

Ignore Tony, he's a comedian.

 

[Kev123456]

does joining the feed to the vent also help to stop sucking in air or are you saying that removing the piping that has the manetic sludge in it will solve the air problems and that joining the feed and vent will keep water moving on expansion and contraction stopping iron biuld up in the future?
Thanks,
Kevin

 

[jeff the gasman]

does joining the feed to the vent also help to stop sucking in air or are you saying that removing the piping that has the manetic sludge in it will solve the air problems and that joining the feed and vent will keep water moving on expansion and contraction stopping iron biuld up in the future?
Thanks,
Kevin

That's how I've dealt with it for a long time now and as yet haven't been back to one with the same problem.
The magnetite builds up in the neutral part of the hydraulics.
Swapping the pipework as is may cause the same issues later but will solve the problem.

 

[jeff the gasman]

The build up of magnetite alters the way the pump affects the system, creating high and low pressure zones.

 

[Kev123456]

Thanks for the advise, I still plan to cut out the pipework and replumb as you said on the weekend. The only thing I can't get my head around is I never had the air problem when the old boiler was in place. Do the new boilers these days show up this air problem much more then my old one did?
Thanks,
Kevin

 

[jeff the gasman]

Thanks for the advise, I still plan to cut out the pipework and replumb as you said on the weekend. The only thing I can't get my head around is I never had the air problem when the old boiler was in place. Do the new boilers these days show up this air problem much more then my old one did?
Thanks,
Kevin

Draining the system can pull debris from the tank which would compound the problem.

 

[Kev123456]

Thanks, when I connect the cold feed by teeing into the vent would you recommend a perticuler dimension up the vent pipe (eg 6" up from horizontal flow pipe)?

 

[jeff the gasman]

Thanks, when I connect the cold feed by teeing into the vent would you recommend a perticuler dimension up the vent pipe (eg 6" up from horizontal flow pipe)?

Wherever it's easier mate. Let us know how it goes..

 

[Kev123456]

Thanks will do. Just one really silly question left, if I Tee cold feed into Vent what stops it flowing from the cold feed pipe and up the Vent pipe and back into the FE Tankwhen the pump is not operating?

 

[jeff the gasman]

Water finds its own level