Heat pump blues

[Raabid]

One of the heat pumps in my house is not functioning properly,  the outside unit fan runs, but the line going to the blower unit which feeds the vents is frozen, and the blower unit itself won't turn on.  I'm not sure which is the cause and which is the resultant.     

[dkpd1581]

Can you be a bit more specific.  You identify the line going to the blower as frozen.  Is it the large (suction) line or the small (liquid) line tha is freezing.   Is the freezing going all the way to the outdoor unit and freezing the compressor shell.

In general, you can look for the 3 big suspects:

Airflow issues possibly caused by bad indoor blower motor, dirty filter, dirty indoor coil

Low refrigerant charge

restriction caused by obstructed biflow drier, metering device, kinked liquid line

Let us know and we can go from there

[hvacdrd]

If the indoor fan is not running it would cause the frozen indoor coil. Start by shutting down the system, turn the fan switch at the thermostat to ON and see if the fan is running...

[Raabid]

The fan is not coming on while the cool is off.  It is the larger line that is frozen, and doesn't continue to the outside unit, filters are clean.

[Raabid]

With the fan set to "ON", I pulled the cover off the blower area, the motor sounded like it was periodically trying to kick on.  I spun the impeller, and after a few seconds, it started to turn on its own.  The outside of the pipe is no longer frozen, and there is a inch thick block of ice which was, until recently attached to the coils,  I removed it and placed it in the drain pan.    

Since I have another airhandler right across, from this one, I check it to see how much more airflow there was from it, which was substantially more.  Although the inflow side of the coils was extremely dirty and needs to be cleaned.

Is there a measurement I can take from the motor to tell me if its shot.

[dkpd1581]

Check the capacitor wired to the motor....you will most likely find it defective and outside of 10% of the value listed on the shell. 

Replace the capacitor and then try to start it up...if the motor starts and runs with your help, the capacitor is usually the problem.

[Raabid]

Changing the capacitor out did the trick, thanks a bunch.  Beer's on the way!