Which plumber is right Regarding room thermostat?

[Brianchild23]

Hi there,

We've just moved house and we've had three plumbers round to give us quotes for new radiators, the house is ten years old and some of the radiators are rusted at the corners and dripping. Do they normally do this after ten years or so?

Apparantly there is an issue with having a wall thermostat next to a radiator thermostat.
We moved in last week and haven't had the heating on yet, but our hall is quite big and has three radiators in it, two are quite close to the wall mounted thermostat and one is 6 ft away. All radiators in the hall have thermostatic valves on them and the three plumbers are giving me different advice.

1st plumber says to turn the closest radiator down to minimum on the thermostatic valve.

2nd plumber says all radiators in the hall should have normal valves on them.

3rd plumbers says only the closest radiator to the wall thermostat needs its thermostatic valve removing.

Which is right? And why won't it work as it is?

 

[doitall]

Move the stat to the lounge, would be an even better option.

 

[bengasman]

There is a section in FAQ that will answer all your questions about the how and what of roomstats, trv's and how to set them.

By and large there are 2 ways of doing it "correctly", roomstat in hall/landing or in the lounge; you can argue about which one is best in the same way as arguing if it is better to have front-, or rear wheel drive.

Personally, and so far all my clients have agreed, I much prefer the roomstat in the lounge; it seems to make sense to have the room where you are at the right temperature, rather than the hall right, and the lounge too hot or too cold.
There will always be people who have always seen the roomstat in the hall, and therefore are convinced that is the one and only correct place.

One thing is for sure, there is no way that you should have trv's in the room with the roomstat, irrespective of the number of rads in that room.

 

[Brianchild23]

Thanks for the replys

I don't fancy having it moved into the living room as there are 2 big radiators in there already.

I will look in the FAQ but what I don't understand is how it worked before?

Thats if it worked.

 

[bengasman]

Another issue, though related, is that if rads are rusted and dripping, your system is almost surely suffering from sludge.
Well worth getting rid of that before it becomes a problem, at which point it will be a lot more costly and inconvenient.
Handy info on this in FAQ as well.
Including the installation of a Magnaclean when you get the work done will be a good investment too.

 

[baxpoti]

first is a little confused second and third are both correct.

 

[Nige F]

Hi there,

radiators are rusted at the corners and dripping. Do they normally do this after ten years or so?


?

maybe the valves weren`t made in properly Can`t see rads rotting right through in 10 years without system being so full of sludge it won`t work. I personally would drain and check out the condition of the metal of the rad then re make valves in with compound+ hemp . But then I don`t need to do it for living

 

[bengasman]

...I don't fancy having it moved into the living room as there are 2 big radiators in there already....

You lost me here, what does a tiny little box on the wall have to do with the number or size of the rads?

 

[bengasman]

first is a little confused second and third are both correct.

I agree with number 2 being correct. (apart from sticking the stat in the hall)

How can the one that advices to keep 2 rads with trv's be correct too?

 

[Brianchild23]

...I don't fancy having it moved into the living room as there are 2 big radiators in there already....

You lost me here, what does a tiny little box on the wall have to do with the number or size of the rads?

Thanks for replys I feel I'm getting somewhere now.

You say there can't be TRV's on radiators anywhere near the room thermostat?

If we have the room thermostat moved into the living room then surely we'll have to loose our TRV's on the two living room radiators making the room uncomfortable? Or have I got it wrong?

The system has recently been 'power washed' and the radiators are definatly dripping from the corners not the unions, all plumbers agree on this!

 

[kitch0978]

the lounge won`t be uncomfortable with the room stat in there and losing you 2 TRV`s....the room stat will control the heating to whatever temp you set it to.......so for example if it`s set to 18 degrees and your still not warm enough in the living room then just turn it up a couple of degrees and living room will heat up until the room stat is satisfied.......understand?

 

[Brianchild23]

Sorry yes, I understand now.

So my options are:

Keep the room stat where it is and get rid of all TRV's on hall radiators.

Move room stat into lounge and get rid of TRV's in there.

Just so I understand it, what is the reason that a TRV can't be near a roomstat? FAQ didn't say.

 

[roguetrader]

if you have a TRV on the rad working with the room stat and that TRV is turned right down, your room stat is never going to be satisfied and always calling for heat. the rad needs to have an ordinary valve fitted in place of the TRV or as bodge for now the head taken off the TRV. dont forget to properly dose your system with inhibitor and as bengasman says a magnaclean would be a really good idea.

 

[bengasman]

So my options are:

Keep the room stat where it is and get rid of all TRV's on hall radiators.

Move room stat into lounge and get rid of TRV's in there.

Spot on.

Just so I understand it, what is the reason that a TRV can't be near a roomstat? FAQ didn't say.

Roguetrader's reply is exactly right. Just as an addition to that, although you probably worked it out yourself:

The result of a trv (in the same room as the roomstat) closing before the roomstat is satisfied, is that that particular room will be too cold, whereas the rest of the house will be too hot (because the roomstat will never get warm enough to turn the boiler off)