A follow up. Another TRV Failed almost immediately on sorting out the previous one - same fault: split plastic in the insert. So I looked into some high quality ones in anticipation of replacing all the upstairs ones straight away.
I was surprised to find that Honeywell, Drayton and Danfoss all have plastic inside the inserts. Now I'm sure it's much better quality than the midrange ones that failed - maybe some type of GRP. But right or wrong, after my experiences, I don't want any plastic in them.
Fortunately, the Pegler Terrier 3 fits this criterion, so I drained the system at the weekend and fitted them throughout the upstairs.
It's hard to find pictures online of the valve internals, so for reference, here are pics of the Drayton, Honeywell and Pegler valves. Hopefully this may be helpful to anyone else in a similar predicament.
Thanks to all that contributed, Paul.
ps. I can recommend the Monument Olive Puller to remove the original olives. Sold by Screwfix, and saved me a ton of time.
I was surprised to find that Honeywell, Drayton and Danfoss all have plastic inside the inserts. Now I'm sure it's much better quality than the midrange ones that failed - maybe some type of GRP. But right or wrong, after my experiences, I don't want any plastic in them.
Fortunately, the Pegler Terrier 3 fits this criterion, so I drained the system at the weekend and fitted them throughout the upstairs.
It's hard to find pictures online of the valve internals, so for reference, here are pics of the Drayton, Honeywell and Pegler valves. Hopefully this may be helpful to anyone else in a similar predicament.
Thanks to all that contributed, Paul.
ps. I can recommend the Monument Olive Puller to remove the original olives. Sold by Screwfix, and saved me a ton of time.