I have a geothermal system installed in my home. There are two units - a hydronic heat pump and an airhandler. The airhandler is an independent system from the hydronic heat pump. The airhandler is what is connected to the thermostats in the home. The heat pump is simply controlled with a setpoint device and stores hot/cold water in a tank to be use by the airhandler and/or radiant floor heating.
The heat pump has a L terminal for faults. I have been trying to find a way to send the output of the L terminal of the heat pump to my thermostat where I can be signaled of the fault. I am troubled on how I can connect the L terminal to the zoning equipment on my air handler. I don't believe i can simply connect L terminal from the heat pump to the L terminal on the zoning equipment because they are separate 24vac circuits.
The only way is to wire L terminal to a isolation relay and wire the relay back the common. On the opposite when a fault happens the L terminal is engergized and activates the relay closing the circuit on the other side of the relay. The opposite side of the relay connects the R to the L terminal.
My question is this possible? If so, which relay can I use. I cannot seem to find a relay using 24vac 1amp on both sides of the relay. I appreciate any links to relays that will work.