Sticking Valves - Flushing System

[cujimmy]

I have several radiator thermostatic valves sticking, either open or closed.

A couple of the radiators couldn't be shut off, so I removed the top part and pushed the pin down with the flat of a screwdriver blade. A couple won't open so I've tried pulling the pin up, but to no avail. These are "Westherm" valves which have been in for about 15 years.

I did flush out the whole system a couple of years ago. There are 2 drain valves under the floor hatch by the back door, so I connected a hose to each in turn, connected a mains water hose to the pressurisation point at the boiler and flushed the whole lot through for a couple of hours, closing/opening one radiator in turn.

1) Is there some way that I can add some "rad flush", for want of a better term, to my sealed system in order to get it free from crud ??

2) How often do I need to flush it through ??

3) Is there some "Stuff" that I could add to stop the crud forming ??


All advice much appreciated.

Jim

 

[David937]

You can add Fernox cleaner F3 and circulate for a few hours hot and then drain, to stop crud from forming again add Fernox Protector F1 or MB1 or Sentinel X100.

 

[geanbean]

you can add c/h preservers like Fernox to a system. you can either bye special pumps to go on to your filling loop or use a garden spray bottle with an adaptor. if they are that full of sludge you can drain the whole system down and take each rad off the wall and power wash it outside. If the rads a very old be carefully you dont blow pin holes in them. As to you TRV's after 15 years your probably due some new ones.

 

[gas4you]

Drain a rad on its own, remove the 1/2" nut that holds the bleed nipple and pour in X800. Put back together, open rad valves and run heating system for a few hours as normal.

Drain and flush through each rad on its own using the filling loop and mains pressure.

If your rads don't have these type of fittings, drain system, undo the nut off the bottom of an upstairs rad valve, pour in X800 and do the same.

No need for fancy expensive pressurised attachments to add chemicals

 

[David937]

If the OP has a towel rail he can add it from there too.

 

[cujimmy]

Thanks for the advice guys.

There are a couple of Sentinel stockists close by, so X800 looks favourite.

Seems like I have a bit of work to do!

Cheers
Jim