Norcold 1200 won't cool

[racer0624]

My issue is a little different from other problems I've read about.
For the first 2.5 years reefer temp has maintained 37 set on 4 on either gas or ac. Over the last month of operation I've had to gradually increase the setting to 9 to maintain 40 in reefer and 18-20 in freezer. Performance is the same on gas or ac. I can hear the fan(s) running. Yesterday I added an additional 4" fan blowing up. This am it's still showing 40.
Does this sound like a cooling unit problem?
What else could be going on?

[racer0624]

My issue is a little different from other problems I've read about.
For the first 2.5 years reefer temp has maintained 37 set on 4 on either gas or ac. Over the last month of operation I've had to gradually increase the setting to 9 to maintain 40 in reefer and 18-20 in freezer. Performance is the same on gas or ac. I can hear the fan(s) running. Yesterday I added an additional 4" fan blowing up. This am it's still showing 40.
Does this sound like a cooling unit problem?
What else could be going on?

["007"]

It could be if you are getting good ventilation out of top vent with your fans running.
Check to see if something might be blocking vent opening.

[Ray,IN]

Hopefully the 1200lr service manual from Bryant RV will have some tips.

[RV Wizard]

Once you get the service manual, check the thermistor inside the fresh food section that is clipped on the the fins. There is a test of ohming out the thermistor to be sure it is good. You could also run the unit with the thermistor off the fin and see what results you get. If the unit is less than three years old and you have had it serviced during the first two years it is in warranty and I would not waste another day but get it looked at and documented that this is an issue you want covered. Good luck and keep us posted.

[racer0624]

Thanks for the suggestions. I've moved the thermister up to within 1/2 of the top of fin 2 per Norcold tech. I turned it off for 4 hrs. then back on per another board members' suggestion.(That helped) The thermister checks out ok. I'll check for fallen insulation tomorrow. The reefer now gets down to 30 in am climbing to 38 during the day. Freezer is at 14 this afternoon. I added an extra 4" fan outside that stays on. Temp setting is 7.

[racer0624]

Ray,
Thanks for the Bryant web site. The troubleshooting guide indicates that if the cooling coils are cool w/ a hot flue, the cooling unit is blocked and needs replacement. My coils are hot down low but gradually go from hot to warm to cool toward the upper section. Sounds kinda bad to me.
I have a mobile tech. coming out next week for a KVH issue and I'll get him to look at the Norcold while he's here.

["007"]

The coils will be cooler up top near your working cooling fans and your refer defrosts, cooling coils down during that period.
Your fans are working correctly?

[racer0624]

Yes, the fans are working and I've added an additional 4" fan blowing up.

["007"]

Heres a different installation manual and operating manual. Installation

Operational

I have same refer you have and the thermister for temp is 1 1/4" from the top of fin you say yours is 1/2" from top would be to high, most I have seen are about where mine is. Have found if space on back wall is provide on shelfs the cool air will circulate alot better in box to keep all items at cool temps.
With three fans operation there should be a steady air flow out your roof vent, your floor plan, refer on side wall not on a kitchen slide.

[Ray,IN]

Your vent stack fans should all be at the top of your unit, per manual. You do not want a fan blowing the heat away from the boiler tube/heating element area, just a steady up-draft is required.

[racer0624]

UPDATE on cooling problem.

Mobile tech. was here yesterday. He checked outside and found everything in order. Checking inside he found that the door gasket was torn. This is in the upper center of the right hand door where it has to seal over the hinged metal flap that's mounted to the left door and the black plate mounted to the box. Without the seal I had about a 1/2" X 1/2" open space letting cold air out. I rigged up a masking tape flap gasket that seems to work as the reefer is 31 and freezer is 5 this am. The tech also did the "dollar bill" test all around the box

I feel kinda dumb admitting that I spent too much time looking for a complicated and probably costly solution and never checked the door gasket.

Now I'll learn about gasket replacement.

["007"]

Sometimes the simplest things are what we should look for in the first place, they will stump us everytime.
Its good to hear you have it solved.

[RV Wizard]

Glad to hear is was simple and not so costly a problem. THanks for letting us know.