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Replacement parts for MAYTAG MSD264RHEB | AppliancePartsPros.com

Here is a tech sheet and a manual
http://www.servicematters.com/m...ibrary/docs/16026204.pdf
http://www.servicematters.com/m...ibrary/docs/16025628.pdf

Does sound like a defrost problem but only running for 24 hours seems a short amount of time. I would check the door seals/gaskets. Take a dollar bill, put it betwee the door casket and the frame and pull it out. Work your way around the door. If the bill pulls out with no resistance there is a problem.

Remove the evaporator coil cover.
If the coils are iced/frosted up to the point that the fan cannot pull air through them, then it is a defrost problem.

Force a defrost cycle, see the tech sheet.
If the defrost heater heats up then the adaptive defrost control needs replacing (Item12 Section 4)♦
Be careful that you do not burn your fingers.

If it does not heat up then odds are it is either the defrost element or thermostat, see Section 7.
Undo the element and check it with a meter, should be about 30 ohms
Remove one wire from the thermostat and check it with a meter shopuld be 0 ohms when frozen. Note that it opens just above freezing so be sure it is frozen.