How do you take off the radiator valve cap? Honeywell vt15?
There is no screew on top to unlock. I tried to pull it off . Did not try too hard on case I damage it. So how do you take off/
PLease see the link for the picturehttp
www.hav.co.uk/products/shw-detail.asp?pid=12775&cid=991
That's a thermostatic valve. I'm not sure what you mean by cap, although on most models you can replace the thermostat part without removing the actual valve (maybe that's what you mean by cap). I'm not familiar with that model, but some manufacturers/models
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Knowing where you're going to find the valve number starts with knowing what the valve looks like. In simple terms, the valves look pretty much like a small contraption usually metallic in color with a box like shape.