How much to change a TRV please?

[Stephen19]

Just noticed Muggles already talked about the freezing... ah well, least mine has links

What a great idea! Thanks for this tip. I take it that its an easy to use 'freezing' application. I only need one end doing. Gives me plenty of time to change the trv providing I get no untoward issues.
S

 

[mattylad]

Although the radiator itself will still be full of water.

lock down one end, freeze the pipe on the other.
undo radiator at TRV end.

Have you got a paint roller tray left over from your last decorating? they are great to fit under low radiators etc.
you need some rags too.

A blanking plug (approx cost = 70p)

As you pull the radiator off, whip the blanking plug on & hand tighten.
remove the TRV & fit the new one.
You can usually reuse the old nuts that are already on.

What about the olive guys, is it OK to reuse that?
(I have done in the past, just left the nut & olive there and its been fine).

By the way, I cant remember you saying whats wrong with the TRV itself?

re assemble it all, tighten your nuts then undo the lock at the other end & bleed the radiator.


How long do the freezer kits stay frozen for?
obviously best used on a cold system

 

[Stephen19]

Question Matty, do I undo the bottom bolt or the top bolt first after freezing, before quickly adding the blank stopper?

I take it there will be enough movement in the rad at this end depite being fixed still at the other.

And how would the rad be supported, do I jack it up on something?
Thanks again.

 

[mattylad]

Me, I'd loosen the bottom one, undo the top one.

There is usually enough play in the pipes to be able to pull the TRV out of the way while you whip the blanking plug on.

Or there has been in what little I have done (I'm no plumber) and it all depends upon what yours is like.

The radiator for me has always still been left stuck to the wall as is.


Then once the blanking plug is on (to stop more water pouring out) you can remove the TRV fully.

Have the new one ready to refit quickly, I usually have PTFE tape wound on the threads ready.

An extra pair of hands is always helpful, for wiping your brow, supporting the rad, pulling pipes, bringing brews & passing that spanner that you cant find because you put it behind you Oh and running for more rags & emptying water away.

Whats the worse that can happen, it flood your nice wooden floor & ruin it Put plastic sheeting down, the edge folded up the wall 12"
with a slit in it so it can go around the copper pipe where you can tape the edges together to seal it.
Then put an old cloth sheet down on top.

That way your doing your best to protect the floor just in case.

 

[Stephen19]

Brilliant stuff, thanks Matty.
Will get some plastic sheeting down as well, good tip to save the nice parquet woodblock floor from swelling, splitting, warping, bending all outta shape, ha.
S

 

[John506]

Good Luck

Post back how it goes.

 

[HARALIAN]

Wots the chance of videoing this saga and palarva? Popping it on youtube and letting us all have a larf at your expense?!! Am wetting myself here !! Seen it all before ...... Its usually irate decorators who call us out after they find that it aint as easy as it says on the tin!! Wot kinda system is your heating on and why do you believe its the TRV in the 1st place?? My bets on the tenant has turned down the LSV ....LOL Have fun

 

[Softus]

drain and refill

Drain and refill Tony? For one valve? Don't be soft.

It isn't "soft", it's sensible advice for a DIYer.

I'd question the need to do that even for two or three...if you're changing the majority of the valves on a system then maybe there's a case for a full drain down, but for a small number it just wastes time while you're waiting for the drain then refilling and running around bleeding, and in the case of open vent systems potentially having to clear airlocks.

It's pretty far from being a waste, because you get the opportunity to see the quality of the water coming out, and decide on some preventative maintenance if the need arises.

Have you wondered why the TRV needs changing? Very often it's caused by a dirty system. If this is one of those, then changing it without draining is nothing short of incompetent.

And to save you asking, I'd close down the valve at the opposite end to the one I'm changing, break out the 'leccy pipe freezer and freeze the pipe at the end I'm working on (if both ends needed changing, then of course I'd freeze both ends at the same time), stick an ice cream tub under the rad to catch drips and change the valve, air vent closed of course to create a vacuum. 20 mins max per rad, including freeze time, for one valve or 25 mins for both.

Freezing isn't risk free. An professional electric kit is all well and good, but the novice won't have one, and waiting for the system to cool down (at this time of year) will take longer than waiting for it to drain.

If all other rads are shut off, then there will be no air locks. If the cold feed is blocked on an OV system, then it's a good thing to find out now instead of leaving it to create more problems later.

 

[Softus]

Me, I'd loosen the bottom one, undo the top one.

There is usually enough play in the pipes to be able to pull the TRV out of the way while you whip the blanking plug on.

This is a good way to cause anxiety and/or make a mess.

If you're really doing to do this, then drawing some water out of the system will reduce the mess.

Have the new one ready to refit quickly, I usually have PTFE tape wound on the threads ready.

Why on earth would you put PTFE tape on the threads of a radiator valve joint?

An extra pair of hands is always helpful, for wiping your brow, supporting the rad, pulling pipes, bringing brews & passing that spanner that you cant find because you put it behind you Oh and running for more rags & emptying water away.

Good advice.

Put plastic sheeting down, the edge folded up the wall 12"
with a slit in it so it can go around the copper pipe where you can tape the edges together to seal it.
Then put an old cloth sheet down on top.

Also good advice.

 

[Paul Barker]

I change them regularly for £22.50 labour.

Suspend system, drain water off until it is properly suspended which involves sealing all aav's etc.

Then just change it while the water sits in the pipe looking at you. I do isolate other end of rad and drain that particular rad. Also have a quick olive cutter tools because often the new trv is more stubby the olive is too far down the pipe. And anyway that way you can use the shiny new nut.

Never darin down for these jobs it would never pay, I'd be broke.

 

[Agile]

Mattylad says he is a DIYer and perhaps that why he gives advice which is likely to give rise to a claim for a whole new champagne coloured carpet at £3000 for the sake of changing a £22 valve!

A professional does not do a £100 job which will involve a claim for £3000 carpet because of a SINGLE black mark just 8 mm diameter!

Not only the carpet but replastering the whole ceiling downstairs!

I saw a flat where they had claimed a whole new block floor and kitchen at £22k following a water leak from upstairs that only wetted about 2m² !

Tony

 

[Softus]

Paul, I don't know whether there's some North/South divide in effect with this one, because I've never disagreed with you before, but I've never yet come across a system where I've regretted draining down, even for just one rad valve.

If draining exposes a problem, then it's a problem that's worth discovering. Usually the time spent draining is exactly the same as the time needed to gather the tools needed to do the valve change, and sheet up, and explain the job, and start sipping a cup of tea.

 

[Agile]

I taught a trainee a few years ago how to do a snatch change of a rad valve and that proved very useful at a job I sent him to later in a block of flats where it was on a communal system and could not be turned off when the rad started leaking.

We later practiced a quick change with an aquavac which worked very well and with two of us was about 6 minutes per valve without a drop spilt!

However, the liability always has to be taken into account and carpets and rad valve changes just dont go together! I always consider the liability against the job worth and that usually means a written disclaimer or we leave it for the East European men of straw!

Tony

 

[petit_pablo]

Paul, I don't know whether there's some North/South divide in effect with this one, because I've never disagreed with you before, but I've never yet come across a system where I've regretted draining down, even for just one rad valve.

If draining exposes a problem, then it's a problem that's worth discovering. Usually the time spent draining is exactly the same as the time needed to gather the tools needed to do the valve change, and sheet up, and explain the job, and start sipping a cup of tea.

I believe paul is talking about BG jobs at that price. Time is money for contractors so doing valve on bungs is preferable

 

[Softus]

...or we leave it for the East European men of straw!

I would like to politely request that you rethink this kind of comment.