Heating, Air Conditioning, Fridge, HVAC/Heat Pump Issue


QUESTION: Hi Joe.  I had a heat pump fan replaced on a Tempstar. The fan was an aftermarket with different wire colors and an extra wire.   It had a capacitor with it which the tech tied into the old fan cap.  The low speed wire was capped off on the fan circuit. Not sure on the other wiring tech performed.  Upon initial start up after install, the blades ran backward.  The tech reversed the wires on the fan itself to correct the direction (was this the correct action?).  

Here's my primary question.  Upon turning the air on inside, the compressor will start at the same time the fan attempts to.  The fan will start to turn, then stop after just a few turns.  The compressor continues to run.   About 1.5 to 2.5 minutes later the fan will then begin to run again and stay on, except yesterday when I turned the unit on in rain.  After a few minute delay, the fan activated, then stalled after 3 or 4 minutes.  After 3 or 4 minutes of fan stall with compressor running, I turned off unit.  Later in the day it would not come on for at least 4 minutes after the compressor started, so I turned the unit off again.  Today, the fan did its quick stop at start, 2 minute break, then started up.

Any clues?   This seems like erratic behavior unlike anything I witnessed with my old fan. I've been told this is normal behavior by some, and not by others...which has brought me to the experts.  The original fan would start around the same time as the compressor.  I've asked the contractor to return.  Thanks in advance.

ANSWER: Walt, if your referring to the indoor blower fan some models have a time delay on and a time delay off but the delay are usually only 10-15 seconds . The tech probably installed a reversible rotation motor ,meaning after install if it's turning the wrong way they simple reverse a wire harness. To me your either dropping out your voltage to the fan relay which opens a set of contacts to shut off the motor. Try putting the fan switch on the thermostat to ON position from auto , your blower fan should run 24/7 independent of the heat or cooling. If it does the same thing ,drops out you would need to see if you lost power feeding the 24 volt ac fan relay or your losing line voltage 120/220 volt Ac  ( whichever  voltage you have.) you should have a 30 day labor warranty and a one year part warranty. So I would call out the company who installed it. I do not understand " it had a capacitor with it which the tech tied into the old fan cap" your suppose to use the new capacitor that came with the new motor . The old cap you do not need.

---------- FOLLOW-UP ----------

QUESTION: Thanks for such a quick reply, Joe!

Actually, this is the condenser fan over the compressor outside I'm discussing.  It seems to me that the condenser fan should start when the compressor does.  My old one did.  I have no problems with the inside blower.  It kicks on when I turn the air on, as does the compressor outside.    

The capacitor he attached (I think it's some type of capacitor)has two leads.  One went to one of the three leads on the original fan cap (not sure which one).  I don't know where he wired the other, but I think to the fan...not sure on that either.  I'm not sure where the wire he removed from the original fan capacitor went.  Before he installed the new fan, there was only the fan capacitor (which I had tested...good) so I'm wondering if the device he added is causing the delay in the condenser fan starting after the compressor starts, and if so, by design.   I feel such delays can't be good for my compressor, but really don't know enough about HVAC to be sure.    Hours of internet searches turned up nothing on such a delay.   I wish I could offer you more detail on his exact wiring.   It is now different than the original scheme. The OEM condenser fan was a 4 wire plug.   

From your experience, does the delay between the compressor starting, followed by the condenser fan anywhere from 1 - 5 minutes later indicate a problem, or would you consider that normal function?  I don't want to have the contractor make an unnecessary trip out.  Thanks again.  Very much appreciated.


Your outdoor fan suppose to start as soon as the compressor starts no delay period. To me the tech. Did not install a correct motor, outdoor fan motors are either 1075 rpm on the older units and 850 rpm on the newer units. There is no low speed tap , outdoor fan motors are single speed, the indoor fans are multispeed not the outdoor fan. To me you need another tech to look at it . The only time the outdoor fan should shut down when the compressor is running is when your in heat mode and the system goes into and out of defrost. During cool mode the outdoor fans starts as soon as the compressor starts and stays running until the compressor shuts off. The only other time the outdoor fan shuts off or has a delayed start during the cooling cycle would be if you have a low ambient kit, to run your outdoor unit during cool mode is when it is cold outside. If you do not have a low ambient kit , which I doubt you do ,then it should run anytime the compressor runs. You need to call the company and talk to them , I would not run your unit until you find out what's going on,  

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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