Myson TRV 2 Way Replacement Thermostatic Valve Head Only

Myson TRV 2 Way Replacement Thermostatic Valve Head Only
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5.0 average, based on 22 reviews


Replacement head for Myson TRV 2 WAY thermostatic radiator valve (head only - no valve included).

This contract head is interchangeable with the standard Myson thermostatic head (which looks the same, but has red markings and a white bottom section).

Our video shows details of the head, including how to identify a faulty head and instructions on how to replace the head.

 Faulty Myson TRV head compared to a good one

Myson TRV heads are normally very good and last for many years, though one failure that can occur is an internal fault that causes the centre pin to be permanently stuck in the out position. This failure results in the valve not working and a cold radiator. The picture above shows two heads, a faulty one on the left and a good one on the right.

Myson TRV symbols
◯ OffOff
❆ Snowflake
Frost Protection
⬤ Max28°C

TRV 2 Way valve heads made between 1997 and 2012 had a symbol like the greek letter PI. This head, with the EN215 keymark symbol is a direct replacement.

The metal lock ring has a M30 / 30mm x 1.5mm metric thread. Myson has used this thread for a long time, though very old (pre 1997) Myson valves used a smaller 28mm x 1.5mm thread.

The picture below shows what the very old (pre 1997) thermostatic heads with M28 threads looked like. If you need to replace one of these you'll have to buy a new head and an adaptor (available in our store).

Old style Myson TRV head with 28mm thread

Product CodeMZG

Customer Reviews

Average Rating: 5

Myson TRVs

No nonsense, simple to order and pay for, arrived really quickly, the images showing "faulty" or "good" were really helpful, when highlighting where the problem was occurring with the cold rads Thanks (29 Oct 2020, 15:42)

So easy!

Delivered faster than expected and was really easy to swap over. The video and photos of faulty and good really helped, I'm not a plumber - just simply unscrewed the old faulty one and replaced with new one. Voila! Hot radiator now. Thank you. Straight swap - no issues. (22 Oct 2019, 17:59)

Myson thermostats

Received order day after placing it. EXCELLENT service.Well done✅ (17 Apr 2019, 11:36)

Great piece of kit, delivered very quickly.

If, like me, you need this to replace faulty older head, please note that the width of the collar on the original was 1/2 inch, this one is 3/8 inch, so I initially overtightened it, which just pushed the pin back in, stopping the flow. All good now and radiator doing what it is supposed to again. A huge Thank you to the Guys here for their very prompt service. (30 Jan 2019, 16:26)


Thanks to the video it was very easy to identify an issue and replace the head. Ordered and received within 36 hours. Excellent company. (14 Jan 2019, 13:12)
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