This is a common failure part, as well as not shutting off the heat mine was also leaking vacuum. It is a (relatively) cheap plastic part that gets hot as you can see by comparing the old with the new.
Yellowed original valve and naff looking orange hose. | |
New working valve in place with new hose and clamps. | |
Here is a close up. |
Enjoying the renewed action of my climate control system !!!