I've got 3 zone radiant heat with two wired and one wireless thermostats. The Taco SR503 has the green power light but none of the red zone lights are coming on. The end result is that the Hydronic Recirculating Pump is not running, I can 't tell if the Honeywell valves are open or not. The system was working this past spring, so trying to figure out what has gone wrong.
I presume I have 24v because I have my water thermostats wired to the Taco and they are showing power. But when I tried to test the 24v with one multi-meter end to the 24v screw and other end to ground I got nothing . Not sure how to test - besides the front facing 24v screw (there are two), what should the other multi-meter end touch? I am also not getting any power to the valves as far as I can tell. The Honeywell THM5320R wireless thermostat base is showing a call for heat (power, heat, and fan lights are on) as are all 3 zone thermostats inside the house.
I have a HVAC service set for Tuesday, but I want to understand and be able to troubleshoot myself anyway. Any suggestions what my next steps can be? Here is a DIY rough schematic of my wiring. It leaves out most of the heating end of the wiring which involves the Water Thermostats (in the buffer tank) which call for heat and the Geothermal unit.
A slightly different question - One of the Honeywell zone valves had the lever on top set to manual and the other two to Auto. My understanding is that they should all be on Auto. Any insight on this would also be appreciated.
Thanks in advance for your help.
Updated to show all wiring