Ron Gordon
New Member
I am replacing a Wirsbo Zone Control Type 514 in radiant floor. The system currently uses two-wire, single-stage thermostat, Wirsbo Type 507. I am attempting to replace the control with Uponor Zone Control A3031004. The wiring change over seemed very simple; but, when I tried to power up and test the zone thermostat controls, the thermostats started smoking!! Everything I've read, including that of Uponor says that this controller is compatible with any two-wire hydronic radiant floor thermostats, and since Uponor now owns Wirsbo, compatibility would seem like a no-brainer.
Another possibility: I notice that the supply requirement is 24 VAC ± 10% and the old transformer was reading closer to 29 VAC.
Final possibility: I also read that some other thermostats (i.e. Honeywell) needed a small resistor in parallel with thermostat or zone actuator to operate properly. I know that the Wirsbo Type 507 did its magic by pulsing the current and could be seem as a change in resistance at its terminals. Is the effective range different, thus requiring a different resistance baseline?
PS Not using the A3031004 to control the circulation pump. Instead, I use a set-point interrupter that controls all the system power (pump, zone control, & thermostat). This is needed because system also has manually controlled wall radiators in basement.
Another possibility: I notice that the supply requirement is 24 VAC ± 10% and the old transformer was reading closer to 29 VAC.
Final possibility: I also read that some other thermostats (i.e. Honeywell) needed a small resistor in parallel with thermostat or zone actuator to operate properly. I know that the Wirsbo Type 507 did its magic by pulsing the current and could be seem as a change in resistance at its terminals. Is the effective range different, thus requiring a different resistance baseline?
PS Not using the A3031004 to control the circulation pump. Instead, I use a set-point interrupter that controls all the system power (pump, zone control, & thermostat). This is needed because system also has manually controlled wall radiators in basement.
