I flip the switch and the compressor just humms for a few seconds and then it stops. I does not kick on at all. I recently roofed my house and it it did this a few times and then kicked back on. could you please tell me the possible problems and solutions. Its hard to find some one to work on craftsman compressors in my area.

Check the check valve, disconnect the tube between the pump and the tank and power it up and see if it still humms.

Check the condensor unit. May be dusty. Clean it. If still problem replace capacitor.

this is a sign of a bad relay (starter) replacing the relay of the compressor might help if it does not help then you need anew compressor

They are a sealed unit, and you would have to get a Refrigeration tech to install valves to do so, which usually costs close to replacing upper unit (roof unit).
A few things come to mind in your case.
- Are you getting proper 120 AC Voltage?
- Has unit been cleaned recently, as in filter, evaporator, condenser ? Any of these plugged can cause it to shut down.
- is it freezing up due to improper flow from discharge ducts, as in have you closed too many ? Remove filter at ceiling and have a look at coils/fins, at front for frost forming on them when it shuts down.
- How long does it run before compressor kicks out, and how long before it comes back on?
- Does it feel cool when compressor kicks in?

Get back to me with more info if you can, so we can narrow it down better.

Actually, its not kicking on for a few seconds and switching off, its trying to start every few minutes. This could be caused because the compressor is bad, or the start kit which starts the compressor is bad. Since you will not have the equipment to jump start the compressor to see if the compressor is bad or the starter is bad, you will either have to have it inspected by a refrigerator repairman or buy the start kit, i.e. overload and start relay, for your model refrigerator and hope thats the problem. But if it turns out the compressor itself is bad, you will not be able to return this start kit once you install it, since any parts supplier will not accept returns on electrical parts.

No Cooling.
Turn the selector switch to “Cool” and the
thermostat to a low temperature (below room temperature).
The fan runs OK, but the unit does not cool. When the unit
housing is removed, we observe that the compressor does not
run; however, it periodically hums for 15 to 30 seconds.

Possible Causes- Check all of this before buying a new unit, that may not be the solution.

“The voltage could be low – ”
a) Check the voltage between #1 on the
overload switch and the “R” terminal of the
compressor while it is not humming. This
voltage must be 115 volts domestic USA
models or 240 volts export/overseas models.
No less than minus 10% is allowable.
b) Check the voltage from “C” or “R” of the
compressor while it is humming (trying to
start). The latter reading will probably be
lower, but it still must be 103.5 volts
minimum domestic USA or 216 volts
minimum export/overseas models.
If the first reading is above 103.5V domestic USA and
the second is under 103.5V domestic USA, there is
too much voltage drop in the lines - a situation which
must be corrected for the air conditioner to perform
safely and satisfactorily.
2. “A capacitor could be shorted, weak or open.”
Turn the power off.
Caution – There is always a chance that a capacitor is
holding a residual charge, so before touching a
terminal, discharge the capacitor as explained earlier
in this booklet.
Remove capacitors, visually examine them and test
them per instructions given in earlier section on
capacitor testing (See page 9).
If the capacitors test OK, replace them and carefully
reconnect the wires. Be sure the wires are connected
to the right terminals.
3. “Start relay contacts could be open – ” if so equipped.
Turn off all power, then check for continuity with
ohm meter between terminals 1 & 2.
4. “Compressor start winding could be open or
grounded.”
Check compressor windings per instructions. See the
section on the compressors (See page 8).
5. “Compressor could be mechanically stuck.”
This very rarely occurs and when it does, it is usually
after a lengthy shutdown. This should be considered
only after all the above possible causes have been
positively eliminated. To free a stuck compressor, use
your hermetic analyzer according to the
manufacturers instructions.

The distance of the cord is a big deal, 10AWG Cord would be best for this situation. If you have a 50ft cord, make sure that the cord is not wound up on top itself as this can cause a drop in voltage and a spike in amperage. Is the compressor trying to come on at all? If not, then you may have a problem with the selector switch or the thermostat. If the compressor is humming for a few seconds and then stopping and then trying to come on again, it could be a problem with voltage loss. Anything below 98.5 plus or minus 10% is too low the for the compressor to kick on.

the click and hum your hearing is most likely the compressor trying to start. the most common problem is a bad start relay on the compressor. in rare cases the compressor may be bad. if you are mechanicly inclined youc an replace the relay yourself for less than 50 dollars. you will need model and serial number off of the unit and order the part by those numbers. if the compressor is bad you will need to hire a good service company. good luck Peyton

It needs more refrigerant.

There are a couple possibilities:

1. If this is the first time you've started them for the season, one of the compressors might be seized up from sitting over the winter. In which case, new compressor required.

2. If you've just had the compressor serviced including recharging the system, it's possible that the system is simply overcharged. This will stop the compressor from working and giving you the same symptoms as above. If this is the case, you should have the service people come back with some guages and recover some of the refrigerant and the compressor should be fine.

3. If the unit has been sitting and there is a slow leak then there is not enough pressure in the system to allow it to run. The compressor will shut down if there is not enough pressure, but since you say there is a smell, i really doubt this is the case.

Most likely it's #1 or #2 above. If you haven't had it serviced recently, then yeah, it sounds like you're in need of a new compressor.

Good luck.