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2021 nuCamp [email protected] 400 Boondock - Winterproofing instead of Winterizing

Primary components:

* Large pads: https://www.amazon.com/dp/B01MT9EUG9

* Small pads: https://www.amazon.com/dp/B01MUC7XI5

* Govee sensors: https://www.amazon.com/dp/B07R586J37

* 110v heating wire: https://www.amazon.com/dp/B00427COLA

Removing the cover:

The gray water tank:

and drain:

The fresh water tank (and in between):

Fresh water drain and level sensors (this space here is also where I added a Govee Bluetooth temperature monitor):

Large pads installed:

Two small pads on the gray tank— one on the exit pipe and one on the valve outside the frame:

One small pad on the fresh water tank low point (mostly because I had bought a three pack but glad I installed it as it is sufficient on its own most of the time):

Added foil tape:

The orange wire in the previous photo and the taped wire shown below was an additional measure/option to have 110v plug in option to keep everything warm when 110v is available instead of the 12v pads:

Foil bubble wrapped everything (twice, so 4 bubble layers):

Then came the actual insulation— R5(ish) around the entire frame plus sitting between the frame above the corrugated plastic bottom cover (admittedly did not get great pictures of this step):

And all back together again:

Other than the silver wrapping on the drain (and silver bubble visible covering the frame holes) it is impossible to tell anything was changed.  This was a two full day project (one wiring and one insulating) although if I were to have to do it again eliminating the trial-and-error portions it could be done in a day.

This enhancement was much easier than I expected after seeing other posts of the work people had to do in earlier year models to cold-proof their [email protected]  This 2021 [email protected] 400 has all the hoses/pipes up in the cabin except for the fresh water tank drain pipe.  The only things below the floor inside the frame are the two tanks and a bit wiring (mostly level sensor wires). 

I don’t have pictures of the wiring but I wired to an open (new) fuse on the electrical center to two switches: one for the large pads and one for the small pads so I can control them separately.  This ended up being a good move because it appears the large pads may have been mostly unnecessary (see temperature tests below).

(I have a separate post on my dry-toilet install which is why there’s no pad on the black water valve — and the black water tank itself is all above the floor in the cabin.)

I am using three Govee Bluetooth temperature sensors (https://www.amazon.com/dp/B07R586J37) to monitor cabin temperature (“in”), tongue box temperature (“out”), and a third one in the underbelly right by the level sensor wires of the fresh water tank behind the insulation (“under”).  Below is log data from over Christmas when it got into the teens and I had the fresh water tank 2/3 full (temperatures in Fahrenheit):

The above log was mostly a battery level test for myself (standard Boondock solar/battery setup) but the temperatures are relevant to those wondering how well this works, both parked and driving (the last entry).  

It maintained an underbelly temperature in the upper 40s even when it was 11 degrees out over night.  Even switching to just the 3 small pads, without the large tank pads on for several hours, the good insulation did not let the temperature drop.

Very happy with this setup and an quite comfortable taking it out into the cold, with water.