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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Lux 1500 thermostat doesnt make heater come on. worked great

Customer Question

Lux 1500 thermostat doesnt make heater come on. worked great this past summer for the a/c part. looks like its is still good. no obvious damage or loose wiring.
Submitted: 1 year ago.
Category: HVAC
Expert:  Phil replied 1 year ago.


If you can send me a photo of the printed circuit card mounted inside the blower compartment of the furnace... showing where the thermostat wires attach to it, ideally so that I can read at least some of those terminal markings such as R, Y, W, G, C ...I can most likely debug the wiring error for you.

You can use the paper clip icon at the right end of the tool bar above for that.

Customer: replied 1 year ago.
Is the furnace blower the same big box on the roof that is the a/c machine too?
Customer: replied 1 year ago.
i already asked you to call me...
Expert:  Phil replied 1 year ago.

The unit on the roof could be what we call a 'packaged unit' it contains both heating and cooling cooling equipment. If you can get me the brand and model number if it, I can look it up.

The web site charges an extra for a phone call... it is optional on your end.

Expert:  Phil replied 1 year ago.

pictures of roof mounted 'gas packaged AC units'

Expert:  Phil replied 1 year ago.

Picture of a cooling only or heat pump unit that requires an air handler or furnace inside the house, called a split system.

Customer: replied 1 year ago.
i have a friend that is bringing me a ladder to get on top of my roof. i will let you know after i have the photos you asked for. no need to call me until after you see the photos.
Expert:  Phil replied 1 year ago.

If you have a packaged unit on the roof, be careful not to fall off the roof, then remove one or two of the service panels on the side of the unit until you can see the large curvy blower inside... if the printed circuit card is not mounted there it will be behind one of the other panels... its about 6 x 8" square, more or less flat, and generally green colored.

Expert:  Phil replied 1 year ago.

That will work, this dialog box is all we need in most of these cases. There is no rush, I am in until 10 pm, then back all day tomorrow.

If you include a photo of the wiring diagram, printed on a sheet of paper and glued inside the same service panel that will help as well, it needs to be close up, well focused and taken straight on.


Expert:  Phil replied 1 year ago.

Rubber soled boots on the roof along with a rope tied to something on the roof that you can hang onto is a good idea.