Noisy Norcold fridge - model Nr751bb 2018 TAB 400

crowsnest

Our Norcold fridge is pretty loud but maybe that’s just par for the course. How often should the compressor be running? It goes on even if the door has been closed for a long time. 

(Title edited for search purposes,  Moderator)

Mickerly

Model of trailer and model of refrigerator makes a big difference. Could we have a little more to go on?

crowsnest

2018 T@b 400. Nor old model Nr751bb

crowsnest

Typo: Norco not nor old

Tabaz

Not sure if this will address your issue, but give it a read:
https://tab-rv.vanillacommunity.com/discussion/2635/noisy-norcold/p1

johnfconway

Oops, sorry I missed that it is 2-way frig! The link above seemed to involve mostly 3-ways.

Interestingly, we recently replaced 5 ceiling fans with AC-->DC motors. Motors are absolutely silent. Depending on blade design, you do hear air being "cut" at speeds 5 and 6. Also have AC-->DC tabletop Vornado fan we use in T@B 400. It too is very quiet. Begs the question; how hard did Norcold have to work to find a noisy DC fan to cool a Danfoss compressor?

Please ignore what's below:

Suggest you get bluetooth thermometer. Put it in 3-way refrigerator and monitor with minimal opening/closing. Unless all your camping is at very high elevation or northerly latitude, you will find it's an abject health hazard. Replacing it with an efficient 2-way will solve the noise issue. Our Isotherm is whisper quiet and has never exceeded 41 degrees F when ambient was 100 degrees plus and trailer in partial shade.

crowsnest

Ours is a two way fridge 

crowsnest

It’s not running all the time but when it does it’s a bit loud especially noticeable at night 

MuttonChops

There is a 2018 Post in another RV Forum noting the nr751bb extra fan is noisy.
There is a fan mounted on rear of Fridge to help cool the compressor.  You might pull the Fridge out and check the Fan is well attached, not damaged, etc.

Other Forum Post
. . . upgrade it to the newer NR751BB Danfoss powered unit.
. . .
4) New one is NOISY! 95% of the noise is from the cooling fan which runs whenever the compressor is running.Pull the plug on the fan and it is very quiet. Old one is much quieter but a little noisier then the new one with fan disconnected. Maybe get a quieter aftermarket fan?

Mickerly

The NR751 has a Danfoss compressor. We have it's little brother in our 2018 320CS. I added some sound absorbing material behind the unit to make it less bothersome trying to sleep. If it's like mine, there is one layer of bubble rap behind the refrigerator from the factory. Carpet pad works well.

There are 4 screws side ways into the cabinet frame that hold it in. The recommendation to pull it out and check the fan is a really good idea. Make sure the fan turns freely and clean it with a tooth brush. When it's clean, dust free, and spins fine it should be as quiet as it gets.

Do not operate the refrigerator with the fan disconnected. There will be no cooling airflow to remove the heat from the refrigerator.

Let me guess, first you get the fan noise. Then the gurgling sound (the compressor). The fan stops in a few minutes, but the gurgling continues a couple minutes more.  ; )