TRV's union and wall thermostat(?) query

[Rich_H]

I've bought a house at auction and it needs various jobs doing.

I've removed some of the radiators for decorating reasons, and I drained the heating system first. I want to fit TRV's, mainly because the current valves are old and stiff. The rads are quite old and I think the thread sizes are different to the TRV's I saw in Wickes, so I plan to take a valve to a Plumbers merchants and ask.

Question 1: Before I do, can anyone tell me if its just a case of changing a 'union', so that the thread to the TRV can now fit the thread coming out of the (union) radiator?

Question 2: In the lounge there are 3 radiators (its a big lounge) and there is also a heating dial on the wall. I read somewhere that TRVs should not be fitted in rooms with wall thermostats. Can anyone offer more advice on this?

Question 3: Is there anything else I need to be aware of re fitting TRVs? What I mean is, is there anything that could be in the 'heating system' fitted that might affect anything TRV related?

Thanks all

 

[ChrisR]

Q1 yes you change the whole valve, including the bit in the radiator.

Q2 unless it's say a very long lounge with rads at the ends, don't fit trv's in there.

Q3 Check the valves , most these day can go either end, but some have to go on the flow end.

If you're intending to live there more than a year, don't buy cheap and nasty valves from WIckes. Go for a name like Honeywell, Drayton, Danfoss, Myson, Peglers... Try a plumbers merchant.

 

[Rich_H]

Marvellous - thank you.

 

[Dan Robinson]

Honeywell VT117s all the way baby.

Think about a Magnaclean whilst the system is drained - chances are the water is manky anyway.

 

[Rich_H]

Why the Honeywells?

Is the MagnaClean really worth the expense and effort?

Both are genuine questions, I know next to nothing about either product so I'd like to hear your opinion before I ask the guy in the plumbers merchants tomorrow.

Rich.

P.S. The water that came out was black and there's a sticker on the boiler that a rust inhibitor or something had been added to the system (which I presume I have now drained).

 

[Breesey]

The black stuff is the reason you would want to clean the system. When you change all the TRVs flush each rad out outside with a hose too. You can hire a power flusher and do the rest of the system yourself, at no great expense! When you refill the system use an inhibitor eg X100.

The Honeywell TRVs are a good valve - I'd go with Peglar Terriers myself though! they are possibly slightly cheaper but are very good value.

 

[Dan Robinson]

Honeywells are extremely reliable valves with the added bonus that it isa piece of p1ss to change the whole mechanism should there be a problem without chaning the valve body. You also get a choice of heads, and if you're feeling flush in the future - you could upgrade to CM Zone very easily.

The Magnaclean will pay for itself very quickly IMHO.

 

[Rich_H]

I previously posted this question:

"Question 2: In the lounge there are 3 radiators (its a big lounge) and there is also a heating dial on the wall. I read somewhere that TRVs should not be fitted in rooms with wall thermostats. Can anyone offer more advice on this?"

The thing is, my neighbour thinks that the wall dial is related to the original boiler that was in the kitchen. This was replaced with a combi-boiler thats now in a cupboard upstairs.

So, could the wall dial still be in use, with the combi boiler? And if its possible, is there an easy way to check?

My neighbour reckons we can remove it from the wall and just fit TRVs to the 3 rads in the lounge.

I guess another question is "if we just fit the TRV's in the lounge, if the 'wall dial' is still in use, whats the impact of fitting the TRVs?"

Many thanks.

P.S. I bought the Honeywells.

 

[UnionJack]

fitted a magnaclean in my house, worth every penny, as has been said, it pays for itself in the long run

 

[Dan Robinson]

"if we just fit the TRV's in the lounge, if the 'wall dial' is still in use, whats the impact of fitting the TRVs?"

Don't leave the wall thermostat - otherwise they will fight each other for control.

 

[Rich_H]

The wall thermostat is removed and all 16 TRVs are fitted.

The system has been checked and is working fine. I now have some more questions =...:

1. How do we get the X100 into the system?
2. I bought a CalCombi:http://www.calmagltd.com/artman/publish/article_40.shtml
My neighbour, who is doing the work, is planning to fit this to the cold water pipe going into the combi boiler. This seems to be sensible for protecting some pipes, but as I understand it it won't protect the central heating system?
3. If its to be fitted to the central heating system, where is the best place to fit it?
And
4. If we fit this one to the central heating system, should I buy another one for the cold water?
5. Lastly, is this a decent product? The plumbers merchants I go to are very helpful and its what they recommended as they don't stock Magnaclean.

Once again, many thanks for the help to date.

Rich.