Power flush Combi central heating system

[sidedward]

I am about to power flush this system Ideal 32 combi Boiler with 12 rads. Whats the best way to isolate the boiler & power flush the system by connecting the flow & return pipe from the power wash machine into the flow & return of where i have taken the radiator out or ..?
Also after that How do i powerwash the boiler itself? Where do i connect the flow & return from the powerwash machine to boiler?

i am using a machine pictured here

 

[oldbuffer]

1. I wouldn't power flush the boiler. Too much risk of forcing crud into the heat exchanger.
2. Isolate by turning off the flow and return valves, normally under the boiler. However, be warned that these sometimes leak when looked at, never mind when used.
3. Power flushing through radiator connections is the most unfavourable way of doing it. The 15 mm connections restrict the flow rate through all the pipe work.
4. Best place is pump, but not always practical with a combi unless you are gas safe registered and have the pump attachment for the flusher.
5. Consider putting Tees into the 22 mm flow and return, then either replacing them with pipe / fittings, or putting full bore lever valves on with pipes with stop ends inserted on the open side once you have finished.

 

[sidedward]

Thanks Buff, have a go & see.

 

[Agile]

To ideally power flush a system you need to regularly reverse the flow. And really flush through each rad in turn.

Then there is the question of what chemicals to use! I choose after seeing the system and what dirt is in it. But X800 is usually a good choice.

 

[sidedward]

Thanks Agile, i'm using X800 .I used one to no effect .I put 2 more since & let it run for 48 hours & see . Keep you posted.