Thermostatic rad valves

[Bloggsyboy]

I've taken a couple of days off to do some jobs. One is to replace the radiator valves with thermostatic ones. Two questions; 1. Is it a good idea to take the radiators outdoors and flush them out with a hose. 2. We have a room thermostat on the stairs, should I disable it somehow and if so how? (I am leaving one radiator in the hall without a thermostat)
Thanks.

 

[Statia]

I fitted some more TRV's in the summer and took off all rads and flushed them with a hose in the garden. The results are well worth the effort of ten or fifteen minutes extra work per rad. Our house is only eight yrs old but the muck that came out was shocking.

Ensure you put some quality inhibitor in when you're happy the system is water tight.

When you take a rad off, make sure you have some old curtains on the floor in case of spillage. As soon as you lift the rad off the brackets, flip it over so the valve openings are at the top and walk out with it like that to stop any more mess coming out.

 

[Statia]

Forgot to reply to q.2.

Leave the room stat as it is.

 

[Bloggsyboy]

Nice one Statia - thanks for the reply, I have just started on here -it's a great idea isn't it! I was worried that clean water flushed through might speed up corrosion or something.

 

[Statia]

No problem.

When you refill the system after cleaning the rads, add some fernox cleaner or suchlike to the system (eBay is a good place to get it) and run your heating with it in there for a couple of weeks to help loosen of any filth in the system. Then drain the system down again, refill, run until hot, drain down again. Do this a couple of times to ensure the system is nice and clean. Then on final refill, add some quality inhibitor to the system, which will help prevent corrosion.

All this work is as good as a powerflush and a damned sight cheaper You should definately notice your rads feel warmer after.

 

[Bloggsyboy]

Thanks for the tip but won't the rads start to rust immediately if I don't put inhibitor in right away?

 

[Statia]

No

 

[Bloggsyboy]

Going well so far. Fitted three downstairs and four upstairs. Couple of leaks which I had to drain down for and start again. One nut was seized up so bad I ended up placing the TRV at the "out " end but had a chance to flush all the rads out myself outdoors which was good. Some were in tight corners and there wasn't much play in the pipes but I got there in the end. Need to buy a special one for inside the rad case then do two more upstairs to finish off. Then it's time to add the cleaner stuff for a couple of weeks before adding the inhibitor. Best part - no ruined carpets (so Far).

 

[muggles]

Note that you'll need to drain the cleaner out, and preferably flush through with clear water, before you add the inhibitor. Go to plumb centre and buy their own-brand inhibitor and cleaner - it's the same stuff as Fernox F1 and F3, just in a different bottle and at about half the price.