I have a problem I'm hoping someone can help me with. We have a Bryant Plus
80 with an Air Conditioner unit. I haven't used the Air Con for a few days
and today I turned it on and there was no fan. I checked and found the CPU
board just making a buzzing sound. I checked to make sure the fan spinned
freely, which it does. I checked to see if there was 24VAC from the
transformer and there is. I reseated all the connectors on the board, but
there was no change. I did not remove the board though, so the top
connections were not reseated, but they seem to be for the heating area.
One note I should mention is when the Electronic air cleaner filter was
connected to the 24VAC output of the transformer the motor was going on and
off, so I put a regular air filter in and that solved that problem for the
moment. Now I'm wondering if the transformer is not putting out enough
power for the blower relay to kick on all the way, or if the relay is bad
and needs more power than it has been getting. I don't want to replace the
board if I can repair it. I'd appreciate any help you can offer, so I can
Pulling the board could be expensive. Some boards can be pulled hot, most
Repairing the board may not be an option, unless you have a lot of
electronic experence. A lot of circuit boards are propitiatory now days.
Even going back 4-5 years.
Who was the rocket scientist that connected the filter to the power supply
to the a/c? Do not let him touch your system again.
The power, VA, available for contol power transformers is pretty limited.
With out knowing specs for all of the equipment it would be impossible to
guess what exactly is the matter. Gut says your air cleaner needs its own
voltage and current source. You could always try the smoke test, put in a
bigger control transformer and see how long it takes for the magic to
Humor is applied to response.
Thanks for your response. The system did work for a few days and up until I
shut it down, since it got cool here, but now getting warm again. There is
a lot of moisture around the furnace unit, too, so I don't know if that's a
factor. This was a local outfit that is very large and has always done our
work. I did notice when I looked again that the main power comes through
the top connection and I would have to disconnect the power (by the circuit
breaker) and remove the board to reseat those connections. The 24VAC is
good though and I'm thinking it's just not giving enough power even though
the voltage is ok. Any other ideas are appreciated.
This is Turtle.
Usely what every is making the most noise is the item with the problem and
humans are the same.
You really need to call a service company because what you have said is just too
many items to start part changing to fix it. Here is the list of items you have
to look at as to the problem.
Relay board but could be where relay plug into it or the spade recievers.
Relay theirself messing up.
Blower Motor bad
Blower Motor Capasitor
For a person here to call a shot here , it would take them being there to
trouble shoot it.
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