PHSC239DSB5 Frigidaire Refrigerator - Freezer cold, but fridge won't reach temp

Crow

Premium Member
Joined
Jul 8, 2019
Messages
9
Location
Vancouver, WA
Model Number
PHSC239DSB5
Brand
Frigidaire
Age
More than 10 years
I have a Frigidaire PHSC239DSB5 that came with the house that I bought. When we moved in back in April of 2016, the fridge was very dirty especially under the unit. The previous owners did not take care of their appliances (washer, dryer, and microwave were all broken). We cleaned it as best as we could and seems to have been running ok since then. However, my wife noticed that food stored in the fridge, especially up on the top two shelves would spoil sooner than expected. I used my FLIR thermal camera to measure the temp and found that the temperate varied a bit throughout the fridge. Upper shelves were warmer than lower shelves, but even the lower shelves were about 3C warmer than the setpoint of 33 F. Fridge seems to have trouble getting below 39 degrees (after about 6 hours constantly running with half the food removed). However, freezer set at 1 F registers as below -10C consistently. I removed the panel to check the evaporator coils expecting a lot of ice to be built up (never checked before). However, they did not have very much ice. Just a layer of frost. I noticed that what looks like some connector shown in photo below may have melted onto the evaporator coils. Not sure what it is or what happened, but I see some plastic that looks melted to the coils. Maybe previous owners tried to thaw it out with a heat gun? Strange. Ice maker works fine. Freezer seemed to come up to temperature without too much time. Checked for leaks in the door seal. Door seal appears fine. It just runs constantly. Wondering if it's low on refrigerant.

It's a 2005 model and I don't want to put a lot of money into it. Looks like I can basically order the same fridge for around $998 on Home Depot. I need a counter depth fridge (standard 36" width, but depth of around 26", height under 70.5") so that really limits my options. Too bad because if that was not a limitation, I could get a much bigger / better fridge for a lot less.
 

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Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
101,360
Location
McMullen Valley, Arizona
Hi,

Do you have a multimeter to ohm test?

Ohm test the resistance of the thermistor in the fresh food section. It should be around 31K - 32.5K ohms in a glass of ice water(waiting at least 5 minutes before ohm testing).

Here's the fresh food section thermistor for your model:
240597203 Sensor


Here's the parts diagram for your model:

The fresh food thermistor is #22 and its located behind its plastic cover #23.

That black stuff is a type of permagum they use at the factory, when it gets old it tends to drop, so don't worry about that, just remove the fallen piece from the evaporator coil and throw it away.

Jake
 

Crow

Premium Member
Joined
Jul 8, 2019
Messages
9
Location
Vancouver, WA
Thanks Jake. I do have a multimeter and I'll look for the thermistor tonight. Approximately where is the thermistor located? You mention that it is located in the fresh food section. Are you referring to the meat or vegetable bins in the fridge section? I looked for a temp sensor in the fridge and I did not see one. Although I did not remove the bins.
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
101,360
Location
McMullen Valley, Arizona
It should be on the left side wall middle to upper portion, look for that plastic cover, that covers it.

Jake
 

Crow

Premium Member
Joined
Jul 8, 2019
Messages
9
Location
Vancouver, WA
I found the thermistor and found it to be around 27.5 kOhms in cold water after 5 minutes. So I think it needs to be replaced. However, I don't plan to fix it. I ordered a new fridge which should be here next week. Although the price of the thermistor is reasonable, I don't know what else will need to be replaced. It's at least 14 years old. With just the fridge door open for about 15 mins, the temp in the freezer increased by about 7 degrees and the fridge runs constantly. 4 out of 5 times that I walk by it, it's running. So I suspect that it could be low on refrigerant. Although the compressor sounds fine. If it was just me, I'd tinker with it some more, but since I have a 1 year old daughter and a wife that doesn't have much tolerance for my experiments in frugality and practicality...guess I need a new fridge.
 

Crow

Premium Member
Joined
Jul 8, 2019
Messages
9
Location
Vancouver, WA
I think I may have been wrong about the fridge running constantly. Although it's usually making some kind of quiet noise, I'm not sure that the compressor is actually fully engaged while it is "running" because if I put my hand near the exhaust at the bottom, many times the air is cool and sometimes it's warm. I suspect that the evaporator fan runs frequently to circulate the air even when the compressor is not running.
 

Crow

Premium Member
Joined
Jul 8, 2019
Messages
9
Location
Vancouver, WA
I ended up moving the fridge out to the garage and I'm using it as a secondary freezer (actually my 3rd freezer). I also replaced the thermistor with a brand new / never used one and I still have the same problem with fridge staying warmer than what the refrigerator thinks it is set to (shows 33 degrees on the display, but is closer to 40). I want to use the fridge, but don't want to replace the entire control board (unless it is cheap and easy). I thought about adding or removing some resistance from the thermistor in order to calibrate it by putting a potentiometer either in series or parallel to the thermistor. But is there an easier way to do this? Is there a tunable "universal" thermistor that I can buy?
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
101,360
Location
McMullen Valley, Arizona
I thought about adding or removing some resistance from the thermistor in order to calibrate it by putting a potentiometer either in series or parallel to the thermistor. But is there an easier way to do this?
I have no clue on how to do that, sorry.

Is there a tunable "universal" thermistor that I can buy?
Not that I'm aware of.

I hope your next new refrigerator is a Whirlpool, Maytag, KitchenAid, or Amana.:)

GE, Frigidaire, Samsung, and LG are much more prone to problems.

Jake
 

Crow

Premium Member
Joined
Jul 8, 2019
Messages
9
Location
Vancouver, WA
"GE, Frigidaire, Samsung, and LG are much more prone to problems."

I agree with you. From now on I will only buy Whirlpool family products. Although I have a GE washer and dryer (3 years old) that I am very happy with. I won't buy any more GE since it's no longer owned by GE. Only reason I went with the Frigidaire is because it offered the most space that my cabinet would hold. I managed to get it to stay in place by placing wheel holders under the wheels and I only paid $1000 for it. In hindsight, I should have gone with the Maytag, but the fridge works for now.
 
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