Seeking stainless steel or otherwise rust resistant rooftop TPRV

[TheOverThinker]

What would you suggest to replace this, on a solar thermal system, San Francisco area:

The old one gave out after 40 years in service, and won't reliably close up after it's activated when the system is past capacity at the tank, and stops circulating.

 

[Tuttles Revenge]

40 years is a good run. Replace with similar.

Took me a few minutes to realize that the piping wasn't cleverly disguised with "Wood Logs"

 

[Sponsor]

 

[Fitter30]

They didn't have HT armaflex back in the day but now they do. Has a uv rating and good to 180°c. Wrapped in aluminum should be as wrapped fiberglass.