[martin417]

Wow, how many ways does this violate the rules?

1) all components must be rated for 125 PSI air pressure. Sprinkler valves are generally PVC, and as such are not rated for pressurized gas (air)

2) Max Cv =.32 for all valves. I don't know what sprinkler valves are rated at, but I would guess >3.2, an order of magnitude more than allowed.

3) max inlet size 1/8 NPT. The smallest sprinkler valve with which I am familiar is 3/4" NPT. again, way out of bounds.

In short, don't even think about it.