Mains flush CH system

[Harpstay]

Any help/advice appreciated!!
My boiler and magnaclense unit are in loft, not easily accessible. Had a blockage in a microbore pipe which a plumber sorted out. Radiator was taken outside and not particularly dirty. Thought it would be a good idea to now clean CH system. Don’t particularly want to take each rad off so:-
A) can I add cleaner, run system, drain down, refill, drain down again and add inhibitor. Would this remove all cleaner
B) How, using a radiator, do I flush system with mains water. I have an outside drain down point but don’t understand how I get mains water, via hosepipe into system.
Thanks for any advice, but as a non plumber please give simplified answers!!

 

[terryplumb]

Is system sealed/ pressurised ? If it is ,why do you need to use a hose pipe to get water into the system ?

 

[Harpstay]

Hi Terry
Yes system is a combi boiler. So once cleaner added and run through system for say 1 week, I will then drain down. Now system is empty I thought it would be advisable to mains flush any cleaner left in system ( have read all cleaner has to be removed and that it is not easy to completely remove it) and to try and remove any crud left in radiators. Then refill and add inhibitor. I will be using Adey Mc3+ and Mc1+. Thanks

 

[terryplumb]

Your magnetic filter should collect what the cleanser puts into suspension. Draining / filling ,run heating, and repeat a few times should clear out any remaining cleanser . And of course check the filter .
I don't use Adey stuff ( no reason ,just never have) ,sentinel X400 is what I use.

 

[Harpstay]

Thanks Terry, so in your opinion filling and draining system a couple of times will be ok, and then add inhibitor to protect system

 

[Mottie]

Each time you fill, run and drain the system you are diluting any cleaner that is left in the system to a point that what’s left will be negligible.

 

[Harpstay]

Thanks Mottie

 

[Madrab]

Be very careful when flushing a microbore system. Microbore can be a nightmare when it comes to a dirty system, especially if they use manifolds. All that cleaning can dislodge bits of debris that can easily block a microbore system, one of the reason an experienced pro will not guarantee powerflushing microbore as it is too easy to create blockages.

I've come across so many where no matter how or what direction mains pressure was used, it was not possible to clear the blockage and a new pipe run had to be installed. I've even managed to use a pressure testing pump before now where I was able to get to both ends of the pipe to blow it through. One pipe took 15bar before the blockage shifted, should have seen the room at other end after that, luckily it was being renovated.

 

[Harpstay]

Thanks for the reply