Peter wrote:

There is a control diagram on one of the squirrel cage housings...trouble is it is covered
in dirt and all attempts to clean the dirt off just obliterates the diagram. This is
curious as the rest of the housing looks very clean and the unit itself looks very clean.
Just the diagram seems to be collecting dirt.

No 24V (no low voltage) coming off the terminals....... . Would it do any good to
remove the relay and transformer to ohm them out ??? Is there anyway to obtain
a replacement part ???

See if there is 120V on the xfmr primary. If there is, Ohm out
the primary. The relay shouldn't be needed just to get 24V from the
xfmr. If no 120V on primary, work back.

A tel. xfmr won't have enough voltage. Big Box store might have
HVAC basic components like this.

Jim


I'm also thinking of trying to get a 24vac source to energize and test the rest of the
circuitry, using one of the old telephone step down transformers....low voltage low
current... any drawbacks to this method ??? (other than turning on line voltage to
test).


I'll be back there tomorrow....too hot to spend the night (condo's suck up heat and
the windows aren't the best in the world). Any other answers or thoughts are appreciated
!!

On Sun, 30 Jul 2006 00:32:55 GMT, Speedy Jim wrote:


Peter wrote:


Need a little help over here......

I have a condo.... with a two part Bryant A/C system. One part is the compressor and
squirrel cage blower vented through a brick wall to the outside. The compressor pumps
freon to a ceiling unit which contains blower and distributes the cooled air into
ductwork.

A/C system is not turning on..... I'm not getting 25 vac ac to the wall unit.
Backtracking the wire...it seems that the low voltage is generated by a transformer
and relay in the ceiling unit. Line Voltage is present on both units, but a
measurement on what should be the low voltage circuit does not show any voltage.



SNIP

Argh! I feel for you.

First, there should be a controls diagram *somewhere*, probably
at the ceiling unit.

Measure if there is 24V right at the xfmr terminals. Work from there.

Jim
ex-DC'er