Powermax 185 flushing issues

[Triggertrevor]

Hi all i've a funny one here hope you can help


I am trying to power flush a range powermax 185.
I have looped out the cylinder by connecting the flow and return heating pipes that come from the cylinder but when i connect the power flushing pump to the central heating pipework downstairs (removed a radiator) i start to back fill the header tank.?????


Now if i've looped out the cylinder but hows water getting back into the cylinder and back filling the header tank.????


Also when the tank is isolated from the flow and return pipework coming from the cylinder, if drain some water off from a radiator the water in the header tank drops..?


I have installed 2 brand new 22mm gate valves on the flow and return side pipework to isolate the water in the cylinder so after i've finished flushing i wouldn't have to drain back down to reconnect the pipework.


Please see pics of central heating flow and return at the left with the gate valves i fitted and domestic hot water on the right





Sorry for the pictures being the wrong way round i've tried rotating them but to no avail

Am i missing something here.


Hope this makes sense and thanks again for any advise on this.

 

[iain85]

Because the cold feed is on the pipework after the boiler. It will be in the boxing below the boiler' also the open vent if used runs up the back the boiler.

 

[Triggertrevor]

Because the cold feed is on the pipework after the boiler. It will be in the boxing below the boiler' also the open vent if used runs up the back the boiler.

Hi cheers for the prompt reply, but wouldn't i be right in saying if that was the case would a 150ltr tank full be able to back fill a header tank with hot heating water as the header is only say 8-10 feet above the cylinder.

Also when i was flushing the header tank water was cold and the cylinder water was red hot due the heating being on before i arrived.

cheers Kev

cheers

 

[iain85]

Hi cheers for the prompt reply, but wouldn't i be right in saying if that was the case would a 150ltr tank full be able to back fill a header tank with hot heating water as the header is only say 8-10 feet above the cylinder.

Also when i was flushing the header tank water was cold and the cylinder water was red hot due the heating being on before i arrived.

cheers Kev

cheers

No, it works on a similar principle to a normal open vent system in that sense. Have a look I'm sure you will find it in the boxing.