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Replacement parts for MAYTAG MSD2641KEU REF - SXS/I&W | AppliancePartsPros.com

Before you replaced the ADC did you try to force a defrost cycle and did the defrost heater come on?

First remove the evaporator cover in the freezer so you can see the coils.
Do not let them de-ice.
If they are heavily iced/frosted over you have a defrost problem.

If we assume that the new ADC is OK.

Unplug the unit.
Remove the wire for one side of the heating element (Item 7 in Section 6) from the wiring and measure it for continuity, usually around 20 ohms or so.

If the heater is OK
Remove one wire to the defrost thermostat (Item 3 in Section 6) and measure it, should be 0 ohms when frozen. Note that it opens just above freezing so must be frozen to check it. Also inspect it, if it is bulged at all replace it even if it measures OK.

If both the above are OK then odds are the new ADC is toast or you have a bad connection somewhere.

If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.
4. When you start always short the meter leads together. This will tell you that the meter is working and if there is any 0 offset.

There is a good STICKY at the start of this forum about it's use.

[COLOR="DarkRed"]ok i have tested the heater it messures 29 ohms the thermost frozen was meshuring 5 ohms so is bad thermostat ? [/COLOR]
Yes the defrost thermostat should be 0 ohms.
5 ohms would indicate a bad thermostat.

[COLOR="DarkRed"]also i melt all the ice hair dryer and it starts to work but ice builds very fast on evaporator that is normal ?[/COLOR]
Yes.
Not ice right away but frost that eventually turns to ice.
Any moisture in the freeze and fresh food sections will condense onto the evaporator coils.
Sometimes if this is excessive it indicates that the door seals are not sealing correctly.
To check for this take a 2 inch strip of paper and place it between the door seal and the fridge's body. Then pull it out to see if the door is sealing. It it pulls out with no resistance then you have a sealing problem. You will have to work your way around the door doing it every 6 inches or so.

[COLOR="DarkRed"] also can i feel the heater get hot is i touch with hand i dont feel it hot ?[/COLOR]
Sorry you lost me here.

You could solder it in but it is easier to use a couple wire nuts.
Then zip tie them up so that they face down so water will not get into them.

Some folks like to seal them with some sealant as an extra precaution. .
If you do this I would recommend you force a defrost cycle just to be sure everything is OK before doing this.

There is foil backed tape that you can get a most hardware stores.
It is used to repair fridge liners etc.
I would use a piece of that to cover the hole.

The foil then will reflect the heat away from the liner.

I think this is the stuff.
Ace® Industrial Strength Metal Repair Tape - Duct & Cloth Tape - Ace Hardware

They do use it to seal ducts so any store that sells heating ducting should have it.

The pros do not use the fiber type of duct tape as it does not seal the good and does not last very long.