Joe417 wrote:
My experience with the Fridge Defend has not been a positive one and I always level the rig. It may work fine on a Norcold or Dometic system but does work for me on a Dutch Aire cooling unit with a Norcold control board.
What we experienced with the Fridge defend is that when it is cutting on and off (I think it is about a 20 minute cycle) it did not maintain adequate cooling. As set by the manufacturer, it cycled on and off even when level and not moving.
I put in a Dutch Aire cooling unit and a Fridge Defend last year. The fridge works great as long as I don't turn on the Fridge Defend. When I do, it turns the system off and on causing the system to go above 45 degrees. I texted back and forth with the manufacturer/creator of the Fridge Defend and was told that the Dutch Aire does run at a higher temp than others. He didn't give me any info on what to put the settings on for the Dutch Aire unit. His final statement was that the cooling unit is bad.
While in my drive way and perfectly level, I was able to change some of the setting on the Fridge Defend and get it to run longer without cycling on and off. But when the truck is on the road it didn't work for me at all. I have to assume that it isn't compatible with the Dutch Aire.
Turning the Fridge Defend off, I have now run the fridge for months and it works great, better than the original Norcold. So for me, the Fridge Defend was a complete waste of money.
Again, it may work correctly on Norcold and Dometic systems.
When googling Dutch Aire cooling unit I see that this is the same as the Amish cooling units (which seem to operate very well...I installed one in one of my RVs). From the Fridge Defend videos, it looks like the 1st high temp shutoff occurs slightly above the normal operating temperature of a Dometic/Norcold cooling unit (~180*C). If the normal operating boiler temp of the Dutch Aire/Amish cooling unit is higher for some reason (...even just 5-10*C higher) then it seems like it would trigger the Fridge Defend temp sensor and cycle the fridge off. Obviously, if the cooling unit cannot stay on at it's normal operating temperature uninterrupted then cooling performance would be heavily impacted.
I would guess the Fridge Defend is designed such that you can adjust those temperature settings for detecting high temp (ie. If out of level by more than 3%/6%) so that your Dutch Aire cooling unit is allowed to operate normally (and only shut it off if the temps get higher). From their videos, it looks like normal boiler operation is around 180*C and Danger Zone temps are at ~225*C. The default setting on the Fridge Defend might be somewhere around 185*C. If you could adjust that to 190*C or even 200*C it seems like it should operate correctly with your cooling unit. I'm not an expert, but that seems logical.
-Chris
