Since this is a commercial box it is possible the second fan kicks in only when the coil temp gets down to a certain temp. this cuts down on snow development . you can look at the wiring to the fans and trace it back to whenre it comes into the blower area . does it go directly to fan a then to fan b? if so verify the voltage is getting to the motor. if it is then the motor is bad.if the power loops through a temp sensor it is possible the second fan doesn't energize till the coil temp is down to freezing. if you see no break in the incoming power to both motors then the motor itself is probably bad. it may be possible to switch power leads from running motor to non running motor. if you do and the bad motor runs the you've got a bad power lead to the motor. good luck.
if you have a refrigeration problem like low charge or in efficient compressor the coil will never get cold enough to activate the second fan. in the old days we would find the temp sensor and blast it with some liquid refrigerant, duplicating the cold coil. a sign of low ref charge is ice formation particularly on incoming feeder lines into coil, the small lines usually real tiny.if there is a sensor for fan it is usually clamped to a pipe in the coil or screwed to the bulkhead of the coil. if you have a refrigeration problem like low charge or in efficient compressor the coil will never get cold enough to activate the second fan. in the old days we would find the temp sensor and blast it with some liquid refrigerant, duplicating the cold coil. a sign of low ref charge is ice formation particularly on incoming feeder lines into coil, the small lines usually real tiny.if there is a sensor for fan it is usually clamped to a pipe in the coil or screwed to the bulkhead of the coil.
Answers & Comments
Since this is a commercial box it is possible the second fan kicks in only when the coil temp gets down to a certain temp. this cuts down on snow development . you can look at the wiring to the fans and trace it back to whenre it comes into the blower area . does it go directly to fan a then to fan b? if so verify the voltage is getting to the motor. if it is then the motor is bad.if the power loops through a temp sensor it is possible the second fan doesn't energize till the coil temp is down to freezing. if you see no break in the incoming power to both motors then the motor itself is probably bad. it may be possible to switch power leads from running motor to non running motor. if you do and the bad motor runs the you've got a bad power lead to the motor. good luck.
if you have a refrigeration problem like low charge or in efficient compressor the coil will never get cold enough to activate the second fan. in the old days we would find the temp sensor and blast it with some liquid refrigerant, duplicating the cold coil. a sign of low ref charge is ice formation particularly on incoming feeder lines into coil, the small lines usually real tiny.if there is a sensor for fan it is usually clamped to a pipe in the coil or screwed to the bulkhead of the coil.
Hi palmer
Happy to help you!!
I would advise you on this occasion to call service.
These guys are good!
A&E factory service does most brands warranty services.
They are open 7days/24hours nation wide.
call tonight! 1-800-905-9505
I am happy to assist you!
Neil
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