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R.G., HVAC Technician
Category: HVAC
Satisfied Customers: 319
Experience:  20 yrs. experience as HVAC technician, state certified contractor.
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We have a 2 stage 12 1/2 ton rooftop HVAC unit, that seems

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We have a 2 stage 12 1/2 ton rooftop HVAC unit, that seems to be blowing out the compressors. 3 within the last 2 years
We placed a monitor system on it, that shuts it down when there is a dropped phase or the voltage goes below a predetermined value, then resets allowing 3 retries before shutting down.
Last week, the temperature was extremely hot and the compressor overheated and
blew out 2 of the three fuses, most likely caused by damaged windings.
The voltage and amperage are fine and the sytem will work a couple months then give us the problem

R G : Hi, I am R. G., sorry you're having trouble today, I will do my best to assist you in resolving you're issue.
R G : If you had a compressor burn out and replacement compressors are burning out prematurely it sounds like there is acid in system. When a compressor burns out it can contaminate the refrigerant and cause it to be acidic which will eat up the windings in replacement compressor. Removing freon and recharging will not remove it all . If this is the problem system will need to be evacuated and flushed out with an acid neutralizer then recharged and filter driers replaced.
R G : You can get an acid test kit at grainger or any HVAC supply store for around 20 to 30 dollars and an acid neutralizer or remover for around 30 to 50 dollars.
R G : First step I would take is to do the acid test . If positive evacuate system do acid flush and replace refrigerant and oil.
R G : Ad filter drier
R G : Let me know if you need any further information. Thanks

They're doing the acid test this week, let you know

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