TRV stuck

Hi,

I've got a radiator that is not warming up and I think the TRV is stuck. I know this happens now and again. If you take the top off, there is a pin. I can't remember, do I push it in or pull it out to release it?

Would a little 3-in-1 or WD40 on it prevent this happening again?

Thanks.

Reply to
Fred
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Don't pull *too* hard - I've known them come out completely, followed by a little fountain of evil black water. And on Christmas Day, too....

Reply to
Huge

Pull it out. Then check it's working by pushing it in and releasing it a few times. The total movement is only a few millimetres.

Lubricant might help, but usually they are stuck internally due to crud inside.

A good tip is to open all the TRVs full when the heating goes off for the summer. The only problem is that other people go around closing them thinking "We don't need the radiators on in this weather." This, of course, is the converse of the present problem where they whack them up full because "The radiator's gone cold."

I do wonder how much "carbon" could be saved by an advertising campaign to tell people how to use TRVs properly.

Chris

Reply to
chrisj.doran

The pin is pushed to shut off the water flow. So if it is stuck down then it is off.

Pulling it may free it, or you may find it is a free floating pin not actually attached to the valve mechanism in which case pulling it will make no difference.

A few gentle taps with a small hammer on the side of the valve may free it.

Reply to
John Rumm

Or getting rid of the wretched things completely and using sensibly-positioned thermostats and motorised valves of a size and design that you wouldn't mind having them visible. I have used Sauter AXT111 actuators, but they're so far off being a mainstream product that they're too expensive for many purposes - and difficult to find with auxiliary switches.

Guess who's in the process of designing a heating system and wants it fully zoned - 5 rooms - and adjustable to real, understood, temperature values, and set without grovelling on the floor, trying to move a valve between four-and-a-tiny-bit and four-and-a-tiny-bit-and-a-gnat's.

Reply to
Autolycus

I find that often if you tap it inwards firmly with a small hammer it displaces the crud, then springs out on the spring.

Reply to
newshound

In article , Autolycus writes

You could do worse than to look at the multizone RF system offered by Honeywell, sorry I don't have the numbers but it should be easy to find. IIRC, set points are sent to RF radiator valves and the control is done locally. I have no time for the RF fad but think that the only way that multizone control will reach the mass market is that way as both new build and retrofit would find multizone cabling too costly. The Honeywell system claims proportional control and the intelligence to shut down heat in a room that has a window open for ventilation if desired.

My own system has a zone valve for each room but controls for such a system have to be home grown and proportional control using off the shelf components is just not an option.

Reply to
fred

costs about

500 quid for a kit to control 6 existing TRVs. but only provides 2 zones. If you wanted totally independent zones for each room you could add up to 3 extra CM67z controllers at about 80 quid each, providing 2 more zones per controller.
Reply to
Mike Clarke

Damned right.

How many people (like SWMBO, to name but one) come into a cold house, switch the heating on and crank up all the TRVs to max, rather than leaving them set at 2-3 where they were previously set for a comfortable operating temperature, because that way "they'll warm up quicker".

And then later - "bloody hell it's hot in here, I'll open the windows"

Bless her.

David

Reply to
Lobster

Tell me about it. I used to be married to someone who was brought up in a communist country where there were no such things as gas meters and bills in the "very attractive" high rise flats she lived in. Heating on full 24/7 and using the window as a thermostat.

Bless her my arse.

Adam

Reply to
ARWadsworth

That's what happens when you say you don't believe in God :-)

Reply to
Andy Hall

Try working in an office that has air conditioning - and women - and a remote control for the thermostat.

Mmmm cold in here I will put it on 32! - then 16!

Reply to
John

It's called an outer control loop - human hysteresis.

As soon as you have this control term in your system, forget about PWM control of the boiler, anticycling and fine grained control.

Reply to
Andy Hall

Indeed, I have given up explaining the concept of thermostats and why raising the setting does not result in an increase in comfort level, I spend my time either slapping heads or installing tamperproof controls :-/

Reply to
fred

That's probably the one but I refuse to navigate such an appalling site to confirm it. I think there is a route to expand it beyond the basic 2 zones.

Reply to
fred

Hmmmm. And you're still sensing room temperatures at the bottom corners of radiators, unless, aiui, you have one CM67z per room.

So, for my system, I'd need:

an HC60NG receiver - £64 five HR80UK valve heads @ £67 - £335 five CM67 @ £60 - £300 (or would that have to be 4 plus

1 other of some sort?) five trv bodies - say - £ 50

i.e. about £750.

Or Five programmable room stats @ £32 £160 Five motorised valves @ £22 £110 Five lockshields £ 10 a wiring centre £ 10 cable and fittings

i.e. about £325

Less sophisticated control, and it's more work wiring it all up, but each item can be replaced if it fails by something functionally identical from another maker, and it leaves £425 to spend on tools, or sweets.

If Tower can make a 22mm motorised valve and bes can sell it for £22, surely it shouldn't be beyond the wit of man incorporate one in a radiator valve for about the same price?

Reply to
Autolycus
[snip - comparison of Honeywell CM Zone Wireless system against hardwired motorised valves]

I'm inclined to agree there. I looked at the CM Zone option as a less disruptive way of applying zones to our existing system but dismissed it as an expensive approach with some practical drawbacks. If we were starting from scratch I'd go for zones with motorised valves but I don't fancy the disruption so I expect we'll settle for a relatively cheap and cheerful addition of a CM927 to the existing system which has TRVs throughout but no room stat.

Reply to
Mike Clarke

I'm glad to see that it's not just my wife who does this.

I might as well replace the heating thermostat with one of those great big knife switches out of a Frankenstein movie, because that's how she treats it.

Reply to
Huge

His name got invoked. But not in a nice way.

Reply to
Huge

I suspect that maybe OTT.

I designed and installed central heating about 6 years ago. I split into downstairs and upstairs zones with separate control. I did accurate heatloss calculations for each room and sized the rads appropriately. TRVs are fitted on all rads except in the two rooms with thermostats, but I simply leave them fully open all the time. With the radiators matching the heat loss from each room, all rooms match each other temperature-wise, and when the rooms with the stats are at the right temperature, so are all the other rooms.

If I hadn't done accurate heat-loss calculations, then TRV's would have been necessary to get desired temperatures, but with proper heat-loss calcs and accurately sized rads, they aren't doing anything. If I'd known how accurate my heat-loss calcs were, I might not have bothered fitting the TRVs at the time. (However, they or something equivalent are needed by Part L nowadays.)

Reply to
Andrew Gabriel

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