Altech TRVs and Lockshields

I would dearly like to hear from as many as possible, who have experienced similar problems to mine.

I have done lots of temperature measurements and adjustments, also swapping TRV heads around to compare. My conclusion is that these valves are just not up to the mark, in 2 unconnected ways.

The main problem is that they shut down the water flow at too low a temperature. The spec. says max. setting air temperature should be 28deg. But in practice, it is between 19deg. And 21deg, depending on the outside air, and boiler water temperatures. Not warm enough for sitting around comfortably.

The other irritating problem is noise generated by both types of valve. In the lockshields, noticeable when they are adjusted only slightly open. In the TRVs, when they are closing. Both types of noise are supposed to be eliminated by adjusting the automatic bypass valve to a low differential pressure. However, even set to minimum, the noise is still there – to a really annoying level on two radiators.

With thanks in advance for your help – and any recommendations for good replacements would be most acceptable!

OK first off never come across Altech valves...from your description they sound rubbish though. The noise may be reduced by reducing the pump speed, also if they're fitted 'backwards' with the flow going into the wrong end of the TRV this can cause noise - many supposedly bi-directional valves still have a preferred flow direction.

As for good replacements, Danfoss RasD² are excellent valves, get them with the matching lockshields and you'll be well away

By altech do you mean ecocalby altechnic,if so they're a damn good valve.never suffered any problems at all.

What system have you got as from my experience I've never seen a noisy one let alone an early closer. Could be you have a one pipe where they're just not suitable and pipeheat is influencing them rather than room heat.

Altech = Graham own brand valves.

brucetah133 said:

The main problem is that they shut down the water flow at too low a temperature. The spec. says max. setting air temperature should be 28deg. But in practice, it is between 19deg. And 21deg, depending on the outside air, and boiler water temperatures.

Click to expand...

Remove the head from the TRV and check what temperature the room reaches. If it is still 19-21 deg, then it's nothing to do with the TRV; it's just that the rad is not giving out enough heat. There could be several reasons:

Rad too small;
Boiler temperature too low;
Rad not balanced.

The other irritating problem is noise generated by both types of valve.

Click to expand...

Are the TRVs bidirectional (two arrows at right angles on the body)?

What speed is the pump set to?

If you set the bypass to a low setting it will always be open, which defeats the object.

Noise can be due to balancing errors.

Thanks for useful points.

Haven't tried checking with the TRV head removed - good idea - will do so on Friday, when it's due to get colder.

Already checked out the other things and reset the BPV to 1.0 bar. Re: the pump setting - boiler is Worccester-B Greenstar 30 CDI heat-only (kept the HW cylinder, uses 2 motorised valves) - no mention of pump speed setting in the manual.

brucetah133 said:

Re: the pump setting - boiler is Worccester-B Greenstar 30 CDI heat-only (kept the HW cylinder, uses 2 motorised valves) - no mention of pump speed setting in the manual.

Click to expand...

A 30kW boiler! How big is your house?

Pump size and speed setting will depend on size and layout of the complete system and should be set by the installer when he balances the system.

I've also got this same issue, mine are not coming on at anything below setting 4 and then they are too hot at 5 anything below 4 is off and thafs with a room temp of 17c. Did you replace the valve as well or just the head.

I've also got this same issue, mine are not coming on at anything below setting 4 and then they are too hot at 5 anything below 4 is off and thafs with a room temp of 17c. Did you replace the valve as well or just the head.

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