Elevated Fridge Temp Issue

[dclark1946]

We are planning on leaving in two days for a three week camping trip but am concerned about fridge interior temp on a Norcold N81X Model N811FRT. Here is what I know:

Fridge location: slide
Fridge interior temp: 60 F
Freezer temp: 0 F
Outside temp: 96 F
Trailer interior temp:78 F (running A/C)
Fan output temp: 114 F (just before the fin assy)
Operation: propane
Temp setting: 5 (max cold)
Indicator lights: gas light on other indicator green
Fan: operating and sounds normal
Burner: can see blue flame
Time on: 20 hours turned on last night outside temp was 78 this morning. Set A/C thermostat for 75 F
Internal fan: Yes standard 2 D cell fridge fan.

We have prepped all of our trailers during the high 90s many times and don't think we have had this issue. This trailer is 2 years old and the fridge has always been operated level. The fridge was removed this spring to replace the warped slide floor. We used the trailer once since then for a Easter campout with cooler temps and it seemed to be ok and food and drink seemed to be pretty cold.

I would like some technical input on this issue so we can make a decision about taking this trip.

Thanks

[dclark1946]

Well my feeble attempts to clean the burner box must have pleased the RV fridge gods at least for awhile. Tapped on the round duct attached to the top of the burner box and some very fine particles fell out. Vacuumed them up and shot compressed air up the big tube attached to the top of the box and a much smaller opening. It did not look like what I expected in side the burner box. Put the cover back and turned it back on in gas mode and it lit. Fridge temp continued to go up by a degree over 15 min or so after turning the unit back on. Concluded I had not helpd the problem. Found a mobil RV tech that could come out today and went off to run last minute errands. Got back home and temp was down to 38 and decreasing. Tech arrived late afternoon and adjusted the burner because flame was a little to big and had a little yellow tip. Outside temp was 99 today. Wife loaded all the food back in the fridge tonight and set the A/C for 75. If it is still good in the morning we will be leaving for the Smokies. Hope it continues to work. Thanks for all the input.

[CloudDriver]

Make your own RV U Tube Manometer

[dclark1946]

After 3.5 hours of ac operation the refer interior temp is 37.9 F. I will check out/ clean the flue while figuring out how to address the potential gas pressure. Will get a new dual tank regulator today and check to see if I have a spare already.

[dclark1946]

After one hour of ac operation the refer interior temp has decreased from 49.7 on gas to 44.2 on electric.

I also made some IR temp measurements on the black ammonia line starting where it exits from the burner box to the the first bottom horizontal run as it starts the progression to the top of the refer.

exiting burner box: 166 deg F
midway to first curve: 141
At first 180 deg curve: 119
Black tank inlet (accumulator??): 115
Black tank outlet: 132
First horizontal lower run: 132

I did try a 12V O2 Cool mini box fan both blowing into the bottom vent and also at the top vent sucking air out. Tried this for 30 min while monitoring refer interior temp it made little difference.

Is the LP regulator the most likely cause for low pressure or could the gas solenoid valve cause a problem. Where would you check gas pressure for refer problem? I checked the range burner again this morning and it appeared to be a good size normal blue flame.

Could you PM me a mobil RV tech recommendation (if you have one) for the North Dallas area just in case I need one? We live in Richardson near UTD. I am thinking it is unlikely that I can get our trailer into a service center on such short notice.

[dougrainer]

4. With respect to L.P. pressure, What kind of gauge is used for measuring that and where would I find one? The range burner looked normal when I bled the gas line after turning on the tank valve in preparation for turning the refer onvbut don't know if that is a good indication. I am assuming that the regulator would be the most likely cause. I believe I have a spare dual tank auto switchover unit I can substitute if the electric operation test shows much improved refer temps. Is there a possible issue if you open the tank valve to quickly?

Opening the valve too quickly will not cause a pressure problem.
You use a MANOMETER to set and test the LP pressure. If you have 10 inches of pressure versus the correct 11.5, that will cause cooling problems. The flame will still look OK. Also, try getting a small 120 volt fan and remove the outside lower door and blow UP with this fan to help remove the hot air. I have a small fan that I install at the upper door after removing the door to blow OUT for troubleshooting slide out installed refers. Doug

[dougrainer]

dclark1946 wrote:

dougrainer wrote:
1. You ARE level?
2. Your temps do not compute 0 in the freezer but only 60 in the refer?
3. Based on your temp readings, your Norcold should be in LOCK OUT(n or NO/CO)
4. I believe your temp readings from your last post, but the refer should be locked out.
5. Based on your temp readings, it would indicate a blocked Cooling unit. Your temp readings are exactly what a blocked cooling unit would do. But, I do not believe you have a blocked Cooling Unit.
6. You need an LP pressure test to verify the LP pressure is correct (11.5 inches w/c).
7. You need to operate on 120 and see what happens. Doug

PS, since the refer was removed for the repair, it is possible when they reinstalled, they caused some type of rear ventilation blockage or damaged the upper cabinet that seals off the rear top cabinet of the refer. Being in a slide room, the ventilation is critical, but as I stated, the refer should be in lock out mode.

Doug,

1. Thanks for your input. I verified trailer is level using the trailer levels and using a level on the floor in front of the fridge. The trailer is in it's normal concrete pad parking spot in our back yard parking spot.

2. I have switched the refer to ac operation to determine if this is a gas issue since outside temp is 78 at 6:00 AM. I only have 15A electrical service so always run fridge on L.P. when I need the A/C to operate. Will operate refer on generator if I need to turn A/C back on when the sun starts heating things up

3. The control panel on our Norcold only has two LEDs so it can only indicate faults by lighting the LEDs or flashing. There are flashing green LED codes for temp sense failed operating in backup mode, ac heater failed and fault with refer controls. Not sure if the last code is the same as the NC lockout code you mentioned.

4. With respect to L.P. pressure, What kind of gauge is used for measuring that and where would I find one? The range burner looked normal when I bled the gas line after turning on the tank valve in preparation for turning the refer onvbut don't know if that is a good indication. I am assuming that the regulator would be the most likely cause. I believe I have a spare dual tank auto switchover unit I can substitute if the electric operation test shows much improved refer temps. Is there a possible issue if you open the tank valve to quickly?

5. I will check temps in an hour (switched to ac around 5:45 AM)

6. This morning at 5:30 still operating on LP the refer interior temp was 49.7 the lower refer vent inlet temp was 81 and the upper panel exhaust temp was 118 deg so lower ambient temps helped but not near enough.

If it locked out, it will blink but you could not run the refer or operate the controls. You would have to turn it OFF for 10 seconds and back on to remove the lock out. BUT, if it did lock out and you turned on and off and restarted, if you did not find and fix the problem, it would lock out the 2nd time and the board would not function at all with out a board reset. Doug

[dougrainer]

Ralph Cramden wrote:

dougrainer wrote:

goff1256 wrote:
Turn it off and get a technician these norcold refrigerators burned down motorhomes they have a heating element to help it defrost and they catch on fire this is very abnormal for a refrigerator not to cool down in the interior box when the freezer is down to zero this refrigerator has a problem find the technician turn it off before it burns down your house

ABSOLUTE NONSENSE. Where did you get this bs? Doug

They do NOT have a defrost Heating element
They do NOT catch on fire

Read it on the internet!

If you rely on the internet, your ignorance is excused:B Doug

[dclark1946]

dougrainer wrote:
1. You ARE level?
2. Your temps do not compute 0 in the freezer but only 60 in the refer?
3. Based on your temp readings, your Norcold should be in LOCK OUT(n or NO/CO)
4. I believe your temp readings from your last post, but the refer should be locked out.
5. Based on your temp readings, it would indicate a blocked Cooling unit. Your temp readings are exactly what a blocked cooling unit would do. But, I do not believe you have a blocked Cooling Unit.
6. You need an LP pressure test to verify the LP pressure is correct (11.5 inches w/c).
7. You need to operate on 120 and see what happens. Doug

PS, since the refer was removed for the repair, it is possible when they reinstalled, they caused some type of rear ventilation blockage or damaged the upper cabinet that seals off the rear top cabinet of the refer. Being in a slide room, the ventilation is critical, but as I stated, the refer should be in lock out mode.

Doug,

1. Thanks for your input. I verified trailer is level using the trailer levels and using a level on the floor in front of the fridge. The trailer is in it's normal concrete pad parking spot in our back yard parking spot.

2. I have switched the refer to ac operation to determine if this is a gas issue since outside temp is 78 at 6:00 AM. I only have 15A electrical service so always run fridge on L.P. when I need the A/C to operate. Will operate refer on generator if I need to turn A/C back on when the sun starts heating things up

3. The control panel on our Norcold only has two LEDs so it can only indicate faults by lighting the LEDs or flashing. There are flashing green LED codes for temp sense failed operating in backup mode, ac heater failed and fault with refer controls. Not sure if the last code is the same as the NC lockout code you mentioned.

4. With respect to L.P. pressure, What kind of gauge is used for measuring that and where would I find one? The range burner looked normal when I bled the gas line after turning on the tank valve in preparation for turning the refer onvbut don't know if that is a good indication. I am assuming that the regulator would be the most likely cause. I believe I have a spare dual tank auto switchover unit I can substitute if the electric operation test shows much improved refer temps. Is there a possible issue if you open the tank valve to quickly?

5. I will check temps in an hour (switched to ac around 5:45 AM)

6. This morning at 5:30 still operating on LP the refer interior temp was 49.7 the lower refer vent inlet temp was 81 and the upper panel exhaust temp was 118 deg so lower ambient temps helped but not near enough.

[Ralph_Cramden]

dougrainer wrote:

goff1256 wrote:
Turn it off and get a technician these norcold refrigerators burned down motorhomes they have a heating element to help it defrost and they catch on fire this is very abnormal for a refrigerator not to cool down in the interior box when the freezer is down to zero this refrigerator has a problem find the technician turn it off before it burns down your house

ABSOLUTE NONSENSE. Where did you get this bs? Doug

They do NOT have a defrost Heating element
They do NOT catch on fire

Read it on the internet!

[MySuncoastRV]

1. Try on alternate heat source. If using power switch to gas and vise versa. Recheck after several hours.
2. Remove the outside access cover and carefully feel the heat coil. It should be hot starting at the bottom and gradually going up. If you locate an abrupt change in coil temp it more than likely has leaked ammonia. Usually the smell of ammonia is very noticeable when you open the refrigerator door when this occurs.
3. You can also use compressed air to clean the chimney. If it's partially blocked by a mud dobber, this will give you the same symptom. I use shop air with an air gun that's specially fitted with a 2ft steel brake line that's slightly bent to slide up the chimney after removing the metal flame cover. I'm thinking about selling these custom made tools on my website.

[Lwiddis]

Try an interior battery fan. Cheap.

[dougrainer]

1. You ARE level?
2. Your temps do not compute 0 in the freezer but only 60 in the refer?
3. Based on your temp readings, your Norcold should be in LOCK OUT(n or NO/CO)
4. I believe your temp readings from your last post, but the refer should be locked out.
5. Based on your temp readings, it would indicate a blocked Cooling unit. Your temp readings are exactly what a blocked cooling unit would do. But, I do not believe you have a blocked Cooling Unit.
6. You need an LP pressure test to verify the LP pressure is correct (11.5 inches w/c).
7. You need to operate on 120 and see what happens. Doug

PS, since the refer was removed for the repair, it is possible when they reinstalled, they caused some type of rear ventilation blockage or damaged the upper cabinet that seals off the rear top cabinet of the refer. Being in a slide room, the ventilation is critical, but as I stated, the refer should be in lock out mode.

[dougrainer]

goff1256 wrote:
Turn it off and get a technician these norcold refrigerators burned down motorhomes they have a heating element to help it defrost and they catch on fire this is very abnormal for a refrigerator not to cool down in the interior box when the freezer is down to zero this refrigerator has a problem find the technician turn it off before it burns down your house

ABSOLUTE NONSENSE. Where did you get this bs? Doug

They do NOT have a defrost Heating element
They do NOT catch on fire

[dclark1946]

mike-s wrote:
How and where did you measure the interior temp? Is the fridge empty? Do you have an interior fan?

I have a wireless sensor sitting on the middle shelf in the middle of the shelf. I also have a glass of water with a digital temp probe and the two agree within o.5 deg. Not much food in there now except 6 soft drinks and 2 personal size bottles of water. We took out the egg carton, milk, some produce and some fresh fruit. I do have one of those battery operated inside fridge fans sitting on the bottom shelf.

Condenser fan exhaust temp at top exterior panel on the slide was 134 deg F with inlet air temp at lower fridge panel was 95 deg late afternoon.