Argo Switching Relays

[grossamer2]

I just had a new heating system installed that has two zones with a thermostat on each floor. I have the ARGO ARM-4P because the wter tank is attached to the system and I have room for another zone if i want one in the basement. The problem appears to be when I turn the thermostat up to heat one zone, both zones come on. I can see the lights on both relays come on. Thanks for your help.

[RBM]

Whenever a zone calls for heat, two relays should energize. One is for the circulator and the other, I believe is for the end line switch. To prove out the control, use a test light. Whenever any zone calls for heat, its corresponding 120 volt terminals should be live