TACO controller calling for heat, thermostat isn't

[ItBurnsItBurnsItBurns]

Hey all looking for some help with my boiler's TACO controller. I have an oil fired hot water baseboard system with 4 zones. Came home yesterday and the bedroom (zone 2) was HOT! Touch the baseboard and it's cranking hot, thermostat is turned off. Checked the controller and indeed zone 2 is calling for heat. This continues even with the thermostat pulled off of its mounting base. Is my controller failing in some way? What could cause this, any ideas?
I manually disconnected the red wire thermostat feed from the terminal inside the controller for now but would like to sort this out without having to call in a service. No work has been done to the house and this all worked perfectly during the winter.
Thanks in advance, been lurking on these forums for awhile and have learned much!

 

[Whitenuckler]

Hey all looking for some help with my boiler's TACO controller. I have an oil fired hot water baseboard system with 4 zones. Came home yesterday and the bedroom (zone 2) was HOT! Touch the baseboard and it's cranking hot, thermostat is turned off. Checked the controller and indeed zone 2 is calling for heat. This continues even with the thermostat pulled off of its mounting base. Is my controller failing in some way? What could cause this, any ideas?
I manually disconnected the red wire thermostat feed from the terminal inside the controller for now but would like to sort this out without having to call in a service. No work has been done to the house and this all worked perfectly during the winter.
Thanks in advance, been lurking on these forums for awhile and have learned much!

It is sounding like a problem with the thermostat if you can disconnect it and make the TACO happy.
Maybe bad wiring too. Check the wiring and swap thermostats with one that works.

 

[EatenByLimestone]

Or wire going to the thermostat shorted. I had this happen last year. I swapped the thermostat with no fix. Called a company and explained the issue as I ran through everything I’d done to troubleshoot. He said, it’s the wire. I’m like really?

I snaked a new wire and he was right.

 

[Whitenuckler]

Hey all looking for some help with my boiler's TACO controller. I have an oil fired hot water baseboard system with 4 zones. Came home yesterday and the bedroom (zone 2) was HOT! Touch the baseboard and it's cranking hot, thermostat is turned off. Checked the controller and indeed zone 2 is calling for heat. This continues even with the thermostat pulled off of its mounting base. Is my controller failing in some way? What could cause this, any ideas?
I manually disconnected the red wire thermostat feed from the terminal inside the controller for now but would like to sort this out without having to call in a service. No work has been done to the house and this all worked perfectly during the winter.
Thanks in advance, been lurking on these forums for awhile and have learned much!

Grab a meter and check on ohms wire to wire and wire to ground if there is one. Then short the wires on one ends
and measure on the other end (assuming they are not already shorted together)

 

[ItBurnsItBurnsItBurns]

Thanks for the suggestions... shorted wire makes sense. I will investigate that.