On Nov 5, 8:01 pm, brian wrote:
On Nov 5, 7:00 pm, Jerry wrote:



On Nov 5, 2:18 pm, wrote:

I just am looking for some sort of clue as to what might be wrong
before I call them. The house has an older heat system (elec
baseboard) so there is no huge rush.

As far as I know (caveat : I'm a software engineer, not an AC repair
guy, although I did fix my own heat pump a few years ago when the
relay that controls the reversing coil got sticky), the 24 volts that
powers the thermostat originates at a transformer in the unit. If
there is power to the transformer inside the unit, and no 24 volts at
the thermostat, then you've either got a bad transformer or an open
connection somewhere.

Without that 24 volts, you're not going to switch the main contactor
that turns everything else on.

Jerry

Thanks for the input.

I reluctantly called the installer of the Heat Pump and he agreed to
come out but wants 84$ to check out the entire system because he
didn't install any of the interior parts of the system. All he
installed was a replacement Heat Pump 8 months ago and that is all
thats covered in parts and labor. He strongly suspects that the
problem lies in the Air Handler.

That is why I was trying to figure out what was broken. If its the Air
Handler in the attic, its ten years old and theres no warranty at all
with anyone anymore, so anyone could work on it.

I am currently suspecting that the problem might lie with the
thermostat's transformer. But I cannot find it. I am having a hard
time tracing the actual power line to the thermostat as I wanted to
check the transformer too. I guess my next step is to keep trying to
trace back to find the transformer...but I'm not sure where it could
be and was thinking it possibly was inside the Air Handler case, which
I really don't want to open unless I know what I'm looking for.

phil

I found the papers for the air handler and the transformer is inside
the unit, which I'm sure you guys already knew.

There was also a 'Functional Parts List' which includes things like
Coil and Drain Pans, Capacitor, Filter, 5 amp fuse, Motor/indoor,
Relay/Time delay, Restrictor, tube assembly, Wheel/blower, and
TRANSFORMER. Which I thought was encouraging, hoping that it still
might just be a bad transformer which could possibly be replaced.

Transformer, 40 VA, 200/230V PRI, 24V,SEC...... Trane Part number
TRR01441

The unit is a Trane Model TWG036A140B0

Anyone know if this would be a fixable item, or how likely it would
possibly be to go bad after 10 years?

Thanks

phil