Hot water pump control

I am looking for help with the following problem.
I have a building with multiple air handlers with hot water coils in them. The circulating pump runs constantly pumping hot water to each air handler. At each air handler there is a three way valve controlled by a 24 volt ac thermostat that directs water through the coil if the space needs heat or bypasses if it does not. I am looking to try and control pump operation based on whether the zone needs heat or not. I know that most of your transmitters do not accept voltage on the switch but could I put another relay in between thermostat and transmitter to make it dry. Was hoping there was a wireless solution as running control wires is not an option.



So it sounds like you would have 2 thermostats, each of which would need to control a relay at the air handler to control the 3 way valve. I would recommend the products in this cart:
Please take a look and let us know if you have any questions on this solution.

Thank you,
Travis Elliott