Norcold Fridge compressor cycling frequently?

[RanchoVectra]

Did a search on refrigerators but didn't see that anyone posted a question like this. In our 05 Vectra we have a 4 door Norcold model 1201LRIM which is keeping good temp.

However I noticed last night that it appears the compressor is cycling for 5 sec about every minute - ie, I hear a fan start up (most noticeably outside the coach, but you can also hear it inside) and then pretty quickly shut off. Smetimes the cycling seems to increase to every 30 sec, and the fan noise is even shorter.

I never noticed this before, but it can't be good (can it?). Outside temps are ranging from low 50's to mid-90's, but the coach interior is pretty much a constant 80 degrees. Thoughts?

[RanchoVectra]

Did a search on refrigerators but didn't see that anyone posted a question like this. In our 05 Vectra we have a 4 door Norcold model 1201LRIM which is keeping good temp.

However I noticed last night that it appears the compressor is cycling for 5 sec about every minute - ie, I hear a fan start up (most noticeably outside the coach, but you can also hear it inside) and then pretty quickly shut off. Smetimes the cycling seems to increase to every 30 sec, and the fan noise is even shorter.

I never noticed this before, but it can't be good (can it?). Outside temps are ranging from low 50's to mid-90's, but the coach interior is pretty much a constant 80 degrees. Thoughts?

[vicsryd]

There is no compressor in these ammonia/hydrogen based units. I believe what you are hearing is a fan that moves air through the ducting past the heat exchanger that cools the gas. The fan comes on when there isn't enough air movement by convection alone and the temp goes past a pre-determined value (I have no idea what the temp is). I have noticed mine has shorter cycles at lower ambient temps.

I see you have the 40AD floor plan. That means your upper vent is on the side of the coach instead of the roof (like mine). It may be your doesn't cool by convection as well as a roof mounted vent and so the fan is needed more often??

One thing you might want to consider doing (at your own risk) is to climb up on a ladder and take out the upper vent grate to make sure then vent is clear and the ducting is square and free flowing. I remember John Canfield having a problem in this area that cause premature failure of his 1201LRIM. Apparently when the fridge was installed at the factory they crushed part of the upper ducting and partially blocked the air flow.

["007"]

I have same fridge the cycle of fan noise is good it will keep your box temps where they should be below 40* alot of people had problems last year with defective thermal switch for fans at the top of your refer. One other thing to check in your top vent is to look for a deflector of metal or plastic to force the hot air out when fans are on for heat to get out from top and not get caught in roof area of slide. Some have added deflector in themselves or had dealer do if it didn't have one.

[NoMoreAZ]

Fans (plural) on top of absorber coils turn on at 130 Deg F and off at 115. If you have a side mount top vent, yes air is harder to move out. When does this happen, when sun is on side of coach ehere frig is?

["007"]

Welcome NoMoreAZ to irv2
Thanks for your post on the subject and it does get hot in AZ.
Enjoy the forums and do post often.

[John_Canfield]

If your freezer is about 0 to 10 degrees and the refrig is between 30 and 40, then you are in good shape. The fans will cycle off and on as others have mentioned as they need to.

You do have thermometers in your freezer and fridge, don't you?

[RanchoVectra]

Thanks for the tips, everyone! Yup, I have thermometers, and they are within the ranges - guess last night was the first time I had been quiet enough to hear the fan cycle.

Thanks again!

[SCVJeff]

Although it is rather interesting that they're short-cycling like this, especially at night. As mentioned above there is a hystersys of 20 degrees built into prevent this. If anything, that should give you several minutes minimum runtime before shutdown.