Zone Valve Recommendation?

Caleffi z45

For on/off I'm not cure if the flapper vs ball would make a difference, I have used generic Erie zone valves without a problem, check out the belimo valves. They can be had reasonably on line, I bought a 3 way mix valve and actuator for 217$, Tekmar wanted 400.

I have two taco zone sentry valves. The capacitive charge operator works well but does take a bit of getting used to due to the slight lag. The one major caveat unless they have modified the design is that the valve stem is very weak. When shipped, the ball is "stuck" in the seat material, the actuator can snap the valve stem the first time its opened rendering the valve useless. They replaced my first one but grumbled about it. On my second one I removed the actuator and manually broke the valve loose as it too was stuck. Once the valve is turned out of the as shipped position the sticking is gone and then the valve works fine.

The other general caveat is that the port opening of the valve is quite small. They sell the same valve with different size end connections but the actual port size is the same. The sizing is probably optimized for conventional hydronic systems. I expect that if someone has high flow low temp design the pressure drop may be higher than desired. If you design the system and figure out the required Cvs this shouldn't be a surprise but many folks don't.

I've just got standard Erie ones, they work & that's about all I can say about them I guess. I have had to replace the odd end switch in a couple, couple more have been going for 20+ years on the same end switch.

One of these days I plan to change out the Taco with a valve with a larger CV as the pressure drop across the Taco is causing ghost flows elsewhere. Since I took the Siegenthaler's course, I want to start from scratch with my piping but hard to justify since my system works as is.

The actual stem on the Sentry valve is not weak but there is machined in step where it ties to the actuator drive that makes it real weak. Breaking it loose from the seat the first time around required more torque than I expected. I figured it could have been my screw up the first time around but when it took the new one out of the box and checked it, it had the same issue.

So if the ball gets stuck in the seals hard enough to break the stem (from just sitting around in the box at the warehouse) do they also get stuck from sitting idle all summer?
How long have these been on the market? Anybody know?

I have had them for several years and haven't had any issues except the initial issues. I expect the water in the lines keep them lubricated.

I will speak highly of the Caleffi Z1. Have installed many and have a total of 6 in my own system. I like the sweat ones on copper to eliminate thread adapters and potential leak points. I remove the bottom cover, the E-clip on the stem and the EPDM flapper, before soldering. Takes about 5min total dissasembly and reassembly. Also wrap any valve with a wet rag before applying heat. Haven't had one leak or fail in the 6 years Ive been installing them.

TS