AIR HANDLER ON ZONE SYSTEM WILL NOT STOP

[georgesouthcarolina]

HVAC guy still here and cannot get the air handler on zone system to shut off even when new board and the thermostats are disconnected. Any idea?

[trgams]

Blower relay or blower board bad...? Is someone looking over my shoulder?!?!

[sean88]

Give the guy a break. It's a short between R and G.

Disconnect R and G from unit and ohm out until you find short.

[beenthere]

If he disconnects the green wire from the G terminal, and the fan still runs.

Then if its a heat pump, check to see if the limit is open.

[Swampfox]

Find a tech who knows how to troubleshoot a simple low voltage problem, or possibly a stuck contact on a relay

[georgesouthcarolina]

Turns out there was a small black U shaped wire laying at the botton below the interior board in the unit. Some kind of relay that had fell out. He put both ends of that in and everything works works!

[tinknocker service tech]

if it is electric airhandler wigth heaters i think the sequencer is stuck and not turning fan off