Hotpoint Fridge warm... I think I've got it?
#1
06-09-08, 04:27 PM
Hotpoint Fridge warm... I think I've got it?
Hi all,
I have a Hotpoint model CTX21DA top freezer refrigerator that has stopped cooling properly.
I took it apart the other day and thawed everything out. There was ice around the evaporator coils in the back of the freezer. We also vacuumed most of the dust off the condenser coils.
The freezer got cold right away and the fridge seemed to be working for a day or two, but then it started warming up again overnight. The evaporator was all frosted up already.
Checking further, both the evaporator and condenser fans are running when the compressor runs. I vacuumed the rest of the dust off the condenser.
I thawed everything again, verifying that the water is flowing out the drain tube.
I took the controls apart and found the schematic and tech info sheet they so kindly printed on thin plastic and tucked into a corner of the control housing.
With that in hand I was able to measure the resistance of the heater as 30 ohms, versus the 33 ohms it's supposed to be. That's close enough, isn't it?
Next, I found that there is an open circuit between the blue lead from the timer end of the heater and the other line from the defrost thermostat. Looking at the defrost thermostat, it appears that the leads go into a layer of potting compound that was partially pulled out of its metal shell, and the wires were no longer attached to the small posts which, I assume, connect to the contacts of the bi-metal switch. There was some corrosion in there as well.
When I find something that actually LOOKS broken, I usually take it as a clue. I'm pretty sure I haven't put enough strain on these leads at any point to damage the switch myself. Does it sound to you like I'm on the right track and the part failed in use?
The thermostat is available at RepairClinic.com for about $15. I'm in SE Michigan, the Detroit area, so I wonder if anybody out there can suggest a place where I could pick one up locally tomorrow?
Finally, would it be okay to splice, solder, and heat-shrink the leads into the existing harness as far from the heater as possible, or would things still get too hot for that? Crimp connectors instead?
I read quite a few refrigerator threads in this forum, and it gave me the courage to dig deeper into the problem. I appreciate the resource!
Mike D.
I have a Hotpoint model CTX21DA top freezer refrigerator that has stopped cooling properly.
I took it apart the other day and thawed everything out. There was ice around the evaporator coils in the back of the freezer. We also vacuumed most of the dust off the condenser coils.
The freezer got cold right away and the fridge seemed to be working for a day or two, but then it started warming up again overnight. The evaporator was all frosted up already.
Checking further, both the evaporator and condenser fans are running when the compressor runs. I vacuumed the rest of the dust off the condenser.
I thawed everything again, verifying that the water is flowing out the drain tube.I took the controls apart and found the schematic and tech info sheet they so kindly printed on thin plastic and tucked into a corner of the control housing.
With that in hand I was able to measure the resistance of the heater as 30 ohms, versus the 33 ohms it's supposed to be. That's close enough, isn't it?
Next, I found that there is an open circuit between the blue lead from the timer end of the heater and the other line from the defrost thermostat. Looking at the defrost thermostat, it appears that the leads go into a layer of potting compound that was partially pulled out of its metal shell, and the wires were no longer attached to the small posts which, I assume, connect to the contacts of the bi-metal switch. There was some corrosion in there as well.
When I find something that actually LOOKS broken, I usually take it as a clue. I'm pretty sure I haven't put enough strain on these leads at any point to damage the switch myself. Does it sound to you like I'm on the right track and the part failed in use?
The thermostat is available at RepairClinic.com for about $15. I'm in SE Michigan, the Detroit area, so I wonder if anybody out there can suggest a place where I could pick one up locally tomorrow?
Finally, would it be okay to splice, solder, and heat-shrink the leads into the existing harness as far from the heater as possible, or would things still get too hot for that? Crimp connectors instead?
I read quite a few refrigerator threads in this forum, and it gave me the courage to dig deeper into the problem. I appreciate the resource!
Mike D.
#2
06-09-08, 04:42 PM
Maybe the pressure of ice expansion pulled the wiring apart? I had that happen once myself, by the defrost thermostat. The mfg'er. had strung the wire to it real taut, probably to save a few pennies in production.
It sounds like you pretty much know what you are doing. I'll leave it up to you on how to re-tie in the wiring. That heat shrink tubing is some neat stuff, if you do it right.
It sounds like you pretty much know what you are doing. I'll leave it up to you on how to re-tie in the wiring. That heat shrink tubing is some neat stuff, if you do it right.
#3
06-11-08, 09:46 AM
Cool Results!
Hey Ecman. Thanks for the reassurance.
I picked up the replacement part from the local Serv-all Appliance for $16.
I tested the switch by putting an ohm meter across the leads, expecting closed contacts, but the switch was open, instead. It took me a few minutes to realize that at room temperature the thing was supposed to be open! I stuck it in the chest freezer and re-tested once it had cooled down and, of course, the switch was now closed. I held it in my hand to warm it up and, after a couple of minutes, there was a satisfying "click" and the contacts opened again.
Okay, so I'm a little slow!
I cut out the old one and spliced the new one into the leads (with plenty of slack, this time), soldered, and covered the joints with the heat-shrink tubing. Put everything back together and applied power.
Freezer was down to 19 F within an hour and the fridge was slowly dropping into the sixties. Last night before bed I think I caught it in the middle of its first defrost cycle. The air in the freezer was about 32 and the fan and compressor were off.
This morning the freezer is at 6 degrees and the fridge at 36! We've already made several trays of ice cubes and most of the food is back in.
So, if all stays as it should, this problem is fixed, at least until the next thing goes wrong.
Thanks for the help and for the helpful resource that's the forum!
Mike D.
I picked up the replacement part from the local Serv-all Appliance for $16.
I tested the switch by putting an ohm meter across the leads, expecting closed contacts, but the switch was open, instead. It took me a few minutes to realize that at room temperature the thing was supposed to be open! I stuck it in the chest freezer and re-tested once it had cooled down and, of course, the switch was now closed. I held it in my hand to warm it up and, after a couple of minutes, there was a satisfying "click" and the contacts opened again.
Okay, so I'm a little slow!
I cut out the old one and spliced the new one into the leads (with plenty of slack, this time), soldered, and covered the joints with the heat-shrink tubing. Put everything back together and applied power.
Freezer was down to 19 F within an hour and the fridge was slowly dropping into the sixties. Last night before bed I think I caught it in the middle of its first defrost cycle. The air in the freezer was about 32 and the fan and compressor were off.
This morning the freezer is at 6 degrees and the fridge at 36! We've already made several trays of ice cubes and most of the food is back in.
So, if all stays as it should, this problem is fixed, at least until the next thing goes wrong.
Thanks for the help and for the helpful resource that's the forum!
Mike D.
