Replacement parts for MAYTAG RS2630WW | AppliancePartsPros.com

Here is a manual that should help
http://www.servicematters.com/m...library/docs/SAM0069.pdf

Try to force it ito a defrost cycle.
If the defrost heater heats up, then the board probably needs repalacing.

If it does not heat up check the heater and the defrost thermostat (bi-metal) for resistance.
Note the defrost thermostat must be checked when frozen, it opens just above freezing.

How do you do a force Defost.
Page 21 in the service manual

I also have notice that the refrig freeze department show alot of cold air (white) after day of being defrosted with hair dryer.
If the frost is on the the evaporator coils this may be normal.
Some frost is on the evaporator coils is normal, It is only a problem when it gets heavy enough to stop air flowing through the coils.

If it does not heat up check the heater and the defrost thermostat (bi-metal) for resistance.
You need a meter.
Disconnect one side of the device you are measuring and then measure across it
Defrost thermostat should be 0 ohms when frozen. Note it opens just above freezing so it must be frozen
The heater should be about 20 ohms
How do you do this?

Where is the defrost thermostat?
It is usually clipped onto the evaporator coils

Looks like this unit uses a glass type defrost heater.
Theses are not very reliable and often you can see where it is blown.