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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7581
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Outside AC UNIT starting, fan and blower does not start (at

Customer Question

Outside AC UNIT starting, fan and blower does not start (at any mode), diagnostic light on control board is off. What can be a problem. Model tue060a936k2
Thank you very much.
Aleks.
Submitted: 1 year ago.
Category: HVAC
Expert:  Phil replied 1 year ago.

Hello Aleks,

Tell me a lot about any technical skills you have, and if you have a multi meter to check for power or not.

If you can attach a photo of the printed circuit card inside the blower compartment where the air filter is... and where the thermostat wires attach I can coach you on some testing. Use the paper clip icon at the top right end of the tool bar for that.

.

Customer: replied 1 year ago.
I am construction engineer, but my electrical and electronic skills are very limited. I have multi meter, but don,t know how to set it up. I can not take picture now. Do you think that if diagnostic light is off it can be something else besides of control board? Please direct me what and how should I test.
Expert:  Phil replied 1 year ago.

Hello again Aleks,

If there are no diagnositic lights on the board lit, it is most likely that the furnace is not plugged in, or the breaker that sends power to the furnace from the house breaker panel is off or tripped, OR... that the transformer in the furnace is bad.

https://www.youtube.com/watch?v=ZBbgiBU96mM

Test the door switch and float switch by fitting jumpers around them... not with the volt meter.

Let me know what you can discover, we can go from there without a time limit.

It is also possible that the blower door is not closed properly and the door switch that interrupts control power is open, or that the float switch that is very often placed in the air conditioner condensate line is open due to a clogged condensate drain, or just the float sticking.

Those can be wired in many different ways, some people wire them to cut the power to the control board.

Customer: replied 1 year ago.
Hi Phill. Condensate drane is definitely clogged.How long should I wait after I clean it before try again?
Expert:  Phil replied 1 year ago.

You can try it again right away, and make sure that you clean the float on the switch assembly to make sure it is not sticking too.

-----

We are on the honor system here. Please remember to rate my service before you leave today. It is how I earn a living, and does not increase your charges.

If you need anything else, just let me know. You can continue asking follow-up questions at no additional cost.

Customer: replied 1 year ago.
Phill. Thank you very much. I will do it as soon as I will get back home. I will let you know after it's done and of course I will rate your service.
Aleks.
Expert:  Phil replied 1 year ago.

That will work.

Customer: replied 1 year ago.
Hi Phill. Unfortunately I didn' have a chance to clean drain yesterday , but I didn't locate any switch. How does it look like? What's the best way to clean the line?
Thank you very much
Aleks
Expert:  Phil replied 1 year ago.

Hello again, your system may or may not have a condensate line float switch, if the air handler is in the attic it probably has one, if not, you may not have a float switch

Here are some typical pictures

http://screencast.com/t/WfppU3Lm6v

I work here on my own time and expense, and am only paid if you rate my work.

Please remember to rate my service before you leave today. It is how I earn a living, and does not increase your charges.

If you need anything else, just let me know. You can continue asking follow-up questions at no additional cost.

Customer: replied 1 year ago.
Hello Phill. So I f I don't have this switch, does it mean that drain line not cause my problem?
Expert:  Phil replied 1 year ago.

If you do not have the switch then the problem will not be a bad switch but some other item that I had mentioned previously, such as the blower door switch, or some other defect that we will have to search out and discover.

If you have the furnace filter door closed properly, next step is to use a multi meter to check for voltage at the furnaces 24 volt transformer.

If you can send me a well lit, well focused, close up photo of the wiring diagram glued to the inside of the furnace door, I can mark it up with trouble shooting instructions and coach you on the diagnosis.

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

.

Customer: replied 1 year ago.
Hi Phill. Your service was great.
Aleks
Expert:  Phil replied 1 year ago.

You are welcome Aleks

...........

I work here on my own time and expense, and am only paid if you ratemy work.

We are on the honor system here. Please remember to rate my service before you leave today. It is how I earn a living, and does not increase your charges.

If you need anything else, just let me know. You can continue asking follow-up questions at no additional cost.

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