Montgomery Ward refrigerator, made by Maytag, Model NENS228GZA. I keep a thermometer in the fresh food side of the refrigerator and yesterday it had moved from a normal 40 degrees to 50 degrees. The freezer showed b/n 20 and 30 degrees. We hadn't been home much, so it wasn't a matter of opening the door too often. The ambient house temp was around 70 degrees with 55-60 percent humidity, which is unusual. I cannot rule out the door being partially open, but I did not notice it before I opened it late in the day. I started by vacuuming underneath the unit and around a fan that was located underneath the unit. Using an exploded diagram obtained from the internet, it looks like the condenser is not a set of coils, but something like a sheet rolled up into a box looking "thing." The fan I cleaned was blowing onto the condenser. I did not really clean the condenser, that seemed impossible since I was looking at the side of it from the back of the fridge. The inside fan located in the back of the freezer was running fine. There isn't a fan inside the fresh food section of the fridge. I removed the cover in the back of the freezer to reveal the evaporator coils. They were frosted over from top to bottom and, in my opinion, the layer of frost was fairly thick. I defrosted the coils using a hair dryer, after unplugging the fridge. I then plugged the unit back in, put some ice trays in the freezer, and put the thermometer back in the fresh food section. After an hour or so, there was frost building up on the evaporator coils again, I did nothing. That was around 10pm. This morning at around 7am the water in the ice trays are now ice and the thermometer shows b/n 20 and 30 degrees like before. The fresh food section thermometer shows just below 40 degrees, which is normal. The frost on the evaporator coils is again fairly thick, but not quite to the top of the coils yet. BTW, I did not reinstall the metal cover/panel in the freezer. I reinstalled only the plastic cover that, I guess, helps deflect air into the fresh food section.
I have never noticed when the compressor was on since I've been around this refrigerator. But it does sound like it is running all the time, but I am not sure of that. I can say the fan inside the freezer is always running when I open the freezer door since this problem started yesterday. I honestly don't remember if it was running every time I opened the freezer before.
So, my question is, is it normal for frost to build up on the evaporator coils so quickly? I was thinking such a quick buildup meant low freon levels. I read in other posts that it could be either a Defrost Thermostat or a Defrost Timer. I have located both on eBay for around $10 each. I was hoping that was going to be the problem, but seeing such a quick buildup of frost made me think that the problem may not be the defrost thermostat or timer. Since there is a panel covering the coils, I just don't know how much frost is normal.
The history of the refrigerator is this. We rent this house. The refrigerator was here when we moved in. We did not have fridge, so our landlord agreed to let us use it with the understanding that if anything happens to it we would be responsible. We've lived here five and a half years.
Thanks in advance for suggestions, opinions, etc. ATL