“I purchased this product to replace a 20 year old AGRO good working valve controller so that I could add an ecobee3 internet thermostat. The ARGO controller removes the 40 volt connection from the other zones when the priority zone is active. This disconnects the thermostat and turns it completely off. This TACO controller switches the ground side of the circuit and the thermostat still operates when the priority zone is active thru the separate common connection. Took some research into the wiring of the ARGO vs. TACO controller internal wiring to fix the problem. It works great.”
“Makes it clear to the homeowner what the system is doing instead of having all the wiring embedded in the zone valves and the boiler. Has also helped with trouble shooting a zone valve problem that didn't send the "open" signal back.”
“Simplified troubleshooting of control valves and adds a priority valve for DWH and other purposes. This is a very well made device that sorts out the wiring mess of a 2 or 3 valve (or pump) hydronic heat system. I installed it in about an hour and the lights clearly show when there is a heat call from a thermostat and when the control valve is open or closed.”
