I installed 10 TRV4 Drayton Radiator Thermostats in my house refurbishment and in seven years since 3 have failed a 30% failure rate. I emailed Drayton & Eberle Controls Schneider and they sent me the following email.
We usually see this fault when the valve bodies are leaking.
I can see from the image you are having leakage from the valve body I can see this by the corroded pins on the device. This would cause the TRV4 bezel to crumble.
Immediately surrounding the pin protruding from the valve body is an adjustable gland seal, identifiable as a black plastic disc with two half-moon shaped indents opposite to each other.
The gland seals you mention are adjustable. We recommend that a yearly maintenance is performed on them by giving them a tighten down clockwise by about an eighth of a turn.
You can do this by putting a gland seal tool or long nosed pliers into the two half-moon shaped indents.
You will get many years of adjustment, but eventually will run out of travel on the seal, this is when the seal needs replacing.
The adjustment of the gland and the replacement of the gland can all be done without the need to drain down your system.
If the bottom seals are in fact leaking. After such a short time this could indicate a dirty system with minerals or metal filings in the water scarifying the bottom seal. Could you please send images of the top of the body with the TRV removed, you will probably see signs of dirty system water there.
I am amazed and wondered if anyone could tell me if the information above is correct?
Thank you
Roy
We usually see this fault when the valve bodies are leaking.
I can see from the image you are having leakage from the valve body I can see this by the corroded pins on the device. This would cause the TRV4 bezel to crumble.
Immediately surrounding the pin protruding from the valve body is an adjustable gland seal, identifiable as a black plastic disc with two half-moon shaped indents opposite to each other.
The gland seals you mention are adjustable. We recommend that a yearly maintenance is performed on them by giving them a tighten down clockwise by about an eighth of a turn.
You can do this by putting a gland seal tool or long nosed pliers into the two half-moon shaped indents.
You will get many years of adjustment, but eventually will run out of travel on the seal, this is when the seal needs replacing.
The adjustment of the gland and the replacement of the gland can all be done without the need to drain down your system.
If the bottom seals are in fact leaking. After such a short time this could indicate a dirty system with minerals or metal filings in the water scarifying the bottom seal. Could you please send images of the top of the body with the TRV removed, you will probably see signs of dirty system water there.
I am amazed and wondered if anyone could tell me if the information above is correct?
Thank you
Roy