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Comap / Myson / Westherm TRV Adaptor

Brand: Potterton Myson
HCO Code: 05A02
Price: £8.03
Ex VAT: £6.69
Stock: In Stock
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Q: Hi, will this fit a Orkli m28x1.0mm to convert it to m30x1.5mm? Thanks

A: Hi No, you need 15A85.
Q: Do you have an adapter that will allow me to fit an M30 threaded head to a Drayton TRV3 valve body.

A: I'm afraid not.
Q: Hello, will this adapt to a Westherm four trv 28mm to convert it to fit a 30mm replacement trv head only? Westherm four is about 15 year s old boy.

A: Hi. Yes it will.
Q: Hello, I have Concerto TRVs and want an adaptor for a Hive head. I have measured the valve base at 28mm with 1mm thread pitch. Will this adaptor work with the 30 mm Hive head?

A: Hi No, you need 15A85 instead.
Q: I have hive thermostats with the RA adaptor attached, will this fit on the radiator to and screw to the RA thread?

A: You will need to use the M30 adaptor on the Hive.
Q: I am trying to attatch a Drayton Wiser thermostat control to a westherm TRV valve. I think this is the part from my research so far. Presumably the thread shown in your picture is 30mm which will fit the drayton wiser top. Then at the bottom of this unit there is a thread of 28.5 to fit the existing Westherm valve that is on the radiator, again by simply screwing it on to the top of the valve. Hence, I would not need to drain the system to fit this adapter.

A: Yes that is correct.
Q: Hello we have a 28mm x 10mm (I think it's 10mm) valve and want to put on a tado TRV. Will this work please?

A: It depends on the make of the valve. Please email us some photos of the valve, as well as the current head.
Q: Does this adapter work with a Danfoss Living Connect. I need a long adapter.

A: It will convert the valve to M30 which you can then fit the Living Connect to.
Q: Hi, I have a radiator valve body with "DN15" marking and a Siemens TRV which seems to have a ~28mm thread. I'm trying to replace it with a 30mm Drayton Wiser TRV. Would this work?

A: Hi. Please email us a photo of it to sales@heatingcontrolsonline.co.uk
Q: Will this adaptor fit on a Westco trv? The Westco is 28mm thread, the new wiser trv's are 30mm

A: Yes it will.
Q: Will this allow me to connect a Drayton wiser head to a herz valve which currently has a westherm thermostat attached?

A: Yes it will.
Q: We have Westherm TRV put in around 1992 when the house was built. I am assuming g that the Westherm adaptor PK21 hand screws( gently tightend) over the top of the one existing in the brass valve? Then the Myson TRV replacement head can be fitted on top of the new adaptor. This can be done with out drains the whole radiator system? Kind regards Chris Kay

A: Yes that is all correct.
Q: I have Pegler 42 EN215 Terrier valves at the moment and want to fit Drayton Wiser heads. Is this the correct adapter?

A: No. You need HCO code 15A51.
Q: Will this work with westherm body 28mm to a Bosch smart trv with a 30 mm head

A: Yes it will.
Q: Could I use this adaptor on my existing westherm valve -m28 1.5 to convert into a valve that would be compatible with the new Hive smart TRV? Hive do not support the westherm connection, but seem to support more standard ones RA, Giacomini, m28-herz, m30.

A: Yes you can.
Q: I have just purchased this adapter, it is the correct one for my TRV. Does it simply screw on top of the existing valve?

A: Please email us a photo of your existing TRV. Yes, it just screws onto the top of the existing body.
Q: I have a Drayton TRV2 valve and need to replace the sensor head. Will this adapter fit the existing body to allow a Drayton TRV4 to be fitted?

A: I'm afraid not.
Q: I have several old Crangrove TRVs in my system, each of which appear to have 28mmx1.5mm threaded connections between the valve body and the head. I wish to replace the heads with a modern 30mm diameter threaded type with a diameter such as the Drayton TR4. Is this possible using one of your conversion adaptors?

A: Please send us a photo of them to sales@heatingcontrolsonline.co.uk
Q: Will this adapter fit on a mistral valve to connect a Drayton wiser head

A: I'm afraid not.
Q: Can I use this to fit drayton wiser head on to my westherum m28 to m30 Regards Andy

A: Yes you can.
Q: Can i use this to fit Drayton Wiser Heads onto a Comap valve

A: Yes you can.
Q: I think I have some Siemens Trade TRVs, 30mm replacement heads definitely do not fit and neither does a Myson adapter. Is this the adapter I need to put Drayton RT412s on?

A: You will need adaptor 15A85 (Orkli) for the Siemens Trade TRV.
Q: I have some 2 radiators with BOSS TRV's that have faulty heads. I think they are approx 10 years old. can you advise if the heads can be replaced directly, if so which would you recommend. If not can this adaptor be used to fit a better new replacement head and if so what would you recommend. Thanks

A: Westherm did make some TRVs for Boss. Please email us a photo for confirmation. sales@heatingcontrolsonline.co.uk
Q: I have a westherm four trv head with a 28 mm thread that I want to replace by a Drayton wiser electronic trv which has a 30mm thread. Does this pk21 do the job? If not what component do I need?

A: Yes it will
Q: Hi. I have an old radiator with a Westherm Four TRV. I bought a new TRV and the fixing nut is too big. The info with it says thread M30 x 1.5 mm. Will this adaptor make it fit? Thanks

A: Yes it will.
Q: Will this product allow me to connect a Drayton Wiser head to a Drayton TRV3 valve?

A: I'm afraid not. We do not currently have a suitable adaptor for the TRV3 Head.
Q: Will this allow me to connect to a westherm 4 Regards

A: This will fit a Westherm 4 body.
Q: Will this adapt old 28mm Drayton valve to the new 30mm tado head

A: I'm afraid not.
Q: I have an old TRV - the only identifying mark is 'Westco' on the top and 'DIN' (or OIN) on the side. I believe it is 28mm. Will this adaptor fit it and allow me to use a standard trv (from B&Q? Cheers - Andrew

A: This will fit the Westco body, but I can't confirm if the B&Q head will fit. Only heads we supply.
Q: Hi, Will this fit onto a siemens trade TRV so we can use a Drayton Wiser smart valve? Thank you.

A: No, you will need the Orkli one. HCO code 15A85
Q: Will this, or the 13D04P , fit a AlTech trv valve?

A: Please email us a photo of your TRV as Altech have done several different ones.
Q: I have an old Myson central heating radiator valve head that needs replacing. There's no model name but there is a code BS 6284 on it. It has no screw head and neither does the valve itself. The head appears to be secured by a metal ring. Please how best for me to replace? Many thanks. Sincerely, James Campbell.

A: Please email a photo of it to sales@heatingcontrolsonline.com
Q: I have some Salus valve bodies that the threads are M28 x 1mm. Do you have adapters for these? I need to go to M30 x 1.5mm for an actuator

A: You will need product code 15A85
Q: we need to replace Temtrol trv heads do you have any adapter

A: I'm afraid not.
Q: I have Drayton Lifestyle. Will this product allow use of Pegler Terrier II head instead of another Lifestyle head?

A: I'm afraid this will not fit any of the Drayton Lifestyle models.
Q: i have an ORKLY M28, i wanna use a honeywell evohome or a honeywell head m30x15. what adaptor do i need?

A: We have got a Orkli adaptor part code 15A85.
Q: I need to replace the head on an old Retting trv, my plumber seems to think a myson 2 way might fit??? any idea

A: Please email a photo of it to sales@heatingcontrolsonline.com so we can identify the model number and recommend a replacement.
Q: Hi, I have a 30mm new Myson TRV head, but need to fit it onto an old 28mm Myson thread, could you sell me a couple of these adapters. Kind regards John.

A: Yes these are the adaptors you need.
Q: Will the PK21 fit on to a Peglar Terrier body (so I could fit an alternative head)?

A: No it won't.
Q: Will the 28mm TRV adaptor (PK21) work with a Drayton 30mm (TRV4) actuator on a 28mm valve (TRV3).

A: No you will need the TRV3 heads http://www.heatingcontrolsonline.co.uk/acl-drayton-trv34-conversion-head-p-238.html
Q: Will this product (PK21) fit a comap westherm 5 rad valve?

A: Yes, it will fit all Comap valves with a M28 thread.

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Adaptors for fitting Myson TRV2Way heads onto TRV bodies with a M28x1.5 head connection (old myson thread).

Also suitable for:
Multi-Fit TRV Head
Honeywell HR80/HR80UK
Honeywell Evohome HR92/HR92UK
Drayton Wiser
Multi-Fit Thermal Actuator


Gareth | 1 reviews

I needed some M28 x 1.5 adapters to use the Wiser Smart Thermostats on existing old Westherm TRVs. This product works perfectly (all six), and is a solidly built metal item.

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