Advice with flushing heating system

[Xavicc]

I've got a heating system on the older side (open vented and with f&e tank) and it has some rads with cold spots and will be getting a new boiler fitted soon as the old one has given up the ghost (unrelated, nothing to do with sludge), Its quite a large property with a lot of pipe work and have been quoted 400quid at the least for a proper powerflush.
I'd consider myself a competent diyer, having done similar in the past and would just hire a machine and do it, however I can't hire a filter along side it, which defeats the object of using chemicals and doing the full job (from what i've been told), I'd also clean the f&e tank at the same time and bung it+
Is there a better way to do the job, I have x800 and x100, which doesn't help me here as the boiler is dead.

 

[Elkato531]

Depends on the price of the whole quote but £400 for a properly done powerflush on a large system sounds like a bargain. You could do it cheaper yourself but if there are problems in the future, the installer could always throw your "amateur" powerflush back at you.

 

[Madrab]

would just hire a machine and do it, however I can't hire a filter along side it, which defeats the object of using chemicals and doing the full job

Nope, you don't need a filter to perform a powerflush. You flush the system using the flush machine and chemicals, then each rad while agitating and then back through the system again. You can use an inline filter too if preferred but it's not needed.

If you specifically do a magnaclense then that uses a dual filter setup but that would probably cost you more than the quote just to get the kit.