I have the following TRV installed on our lounge radiator and I am experiencing some problems with it and would appreciate any advice before I contact the manufacturer.

https://www.screwfix.com/p/white-ang...v-15mm-x/73649

We control the temperature using Hive which is normally situated in the lounge but can be moved to our other reception room depending which we are using most and require accurate temperature control. When the Hive thermostat is situated in the lounge the TRV is set to its highest setting - 5 (27-29C) so as not to conflict with Hive. When Hive is in the other reception room I rely on the TRV to keep the temp in the lounge at the required level by setting it to the correct temp setting.

Today I found the the valve shut tight and Hive reporting the room temp at least 2 degrees below set temp and firing up the boiler to compensate. To my mind the valve should never even be shutting considering the vast difference between temp settings on the TRV and Hive? Do you think the head is faulty, do they have a long hysteresis? This is a replacement for the previous head which appeared stuck in the shut position. With the head removed everything is quite normal the valve itself opens and shuts easily and does not appear faulty.

Richard

In message ,
Tricky Dicky writes
I have the following TRV installed on our lounge radiator and I am
experiencing some problems with it and would appreciate any advice
before I contact the manufacturer.

https://www.screwfix.com/p/white-ang...v-15mm-x/73649

We control the temperature using Hive which is normally situated in the
lounge but can be moved to our other reception room depending which we
are using most and require accurate temperature control. When the Hive
thermostat is situated in the lounge the TRV is set to its highest
setting - 5 (27-29C) so as not to conflict with Hive. When Hive is in
the other reception room I rely on the TRV to keep the temp in the
lounge at the required level by setting it to the correct temp setting.

Today I found the the valve shut tight and Hive reporting the room temp
at least 2 degrees below set temp and firing up the boiler to
compensate. To my mind the valve should never even be shutting
considering the vast difference between temp settings on the TRV and
Hive? Do you think the head is faulty, do they have a long hysteresis?
This is a replacement for the previous head which appeared stuck in the
shut position. With the head removed everything is quite normal the
valve itself opens and shuts easily and does not appear faulty.

I don't have anything that young but all my problems are due to the
valve pin sticking in the closed position.
Usually, scraping the lime scale off, lubricating with plumbers grease
and some vigorous push/pull activity with a pair of pliers cures the
issue for another 12 months.

--
Tim Lamb

On 18/03/2018 18:04, Tricky Dicky wrote:
I have the following TRV installed on our lounge radiator and I am experiencing some problems with it and would appreciate any advice before I contact the manufacturer.

https://www.screwfix.com/p/white-ang...v-15mm-x/73649

We control the temperature using Hive which is normally situated in the lounge but can be moved to our other reception room depending which we are using most and require accurate temperature control. When the Hive thermostat is situated in the lounge the TRV is set to its highest setting - 5 (27-29C) so as not to conflict with Hive. When Hive is in the other reception room I rely on the TRV to keep the temp in the lounge at the required level by setting it to the correct temp setting.

You don't say what "the correct temp setting" is. If you are setting it
to 1 or 2 and the room temp is anything above about 15 then having it
shut tight would not be that surprising. In my experience the temp vs
setting number on any TRV is only a very rough guide, and if it is
critical you may have to do your own calibration.

The TRV you have referenced is not a "top of the range" device so I
wouldn't expect 100% accuracy between the setting number and temperature.

Even the instruction manual says

Note: These temperatures may vary slightly, depending upon the nature
of the installation


Today I found the the valve shut tight and Hive reporting the room temp at least 2 degrees below set temp and firing up the boiler to compensate. To my mind the valve should never even be shutting considering the vast difference between temp settings on the TRV and Hive? Do you think the head is faulty, do they have a long hysteresis? This is a replacement for the previous head which appeared stuck in the shut position. With the head removed everything is quite normal the valve itself opens and shuts easily and does not appear faulty.

Richard



--
Chris B (News)

Tim the valve itself is crud free and the pin pushes and releases easily it is the head itself that is the problem.

Chris the room temp was set at 21C, Hive itself seems to do a good job of not letting the temp rise no more than +/- 1C. On its maximum setting the valve should not be closing until the temp rises at least 6-8C above that. The fact that it was still closed at 2C below the room temp setting means it has an inaccuracy of 10C that's some range? Looks like I will need a better valve. Any suggestions?

Richard

On 19/03/2018 10:56, Tricky Dicky wrote:
Tim the valve itself is crud free and the pin pushes and releases easily it is the head itself that is the problem.

Chris the room temp was set at 21C, Hive itself seems to do a good job of not letting the temp rise no more than +/- 1C. On its maximum setting the valve should not be closing until the temp rises at least 6-8C above that. The fact that it was still closed at 2C below the room temp setting means it has an inaccuracy of 10C that's some range? Looks like I will need a better valve. Any suggestions?

Richard


No, If on its "fully on" setting its closing the valve before the room
gets above 21C, then bearing in mind what you have said about the
freedom to move of the "wet" part it looks like you have a faulty head.

Your web link was to a screw-fix valve I think, if so take just the head
back, they may let you just swap the head and see if another one of the
same type works better.

One final thought, there aren't any washers or spacers between the valve
and the head that have been omitted on assembly? The behaviour you
describe implies that the actuator is "too close" to the valve.

--
Chris B (News)

On Tue, 20 Mar 2018 09:30:50 +0000, Chris B wrote:

On 19/03/2018 10:56, Tricky Dicky wrote:
Tim the valve itself is crud free and the pin pushes and releases
easily it is the head itself that is the problem.

Chris the room temp was set at 21C, Hive itself seems to do a good job
of not letting the temp rise no more than +/- 1C. On its maximum
setting the valve should not be closing until the temp rises at least
6-8C above that. The fact that it was still closed at 2C below the room
temp setting means it has an inaccuracy of 10C that's some range? Looks
like I will need a better valve. Any suggestions?

Richard


No, If on its "fully on" setting its closing the valve before the room
gets above 21C, then bearing in mind what you have said about the
freedom to move of the "wet" part it looks like you have a faulty head.

Your web link was to a screw-fix valve I think, if so take just the head
back, they may let you just swap the head and see if another one of the
same type works better.

One final thought, there aren't any washers or spacers between the valve
and the head that have been omitted on assembly? The behaviour you
describe implies that the actuator is "too close" to the valve.

With some designs of TRV, it's possible that the head may have slipped a
few notches from its calibrated position. ISTR this happening with one TRV
due to "Brute Forcing" an adjustment. If it's a new valve, it might
simply be an incorrectly assembled unit that slipped past QA at the
factory so it would certainly be worth returning it for a warranty
replacement or if it's a very recent purchase, your supplier should be
prepared to offer an alternative make/model with price difference
adjustment if the returned valve looks undamaged enough to be RMAd back
to his supplier.

--
Johnny B Good