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Three Season Trailer to Four Season Trailer

TECMike
Explorer
Explorer
We have a small Sunnybrook three season trailer which we enjoyed tremendously over the years. However, it is a three season trailer, with no insulation or covering underneath for the tanks and pipes.

Would appreciate hearing from folks who have insulated the tanks and bottom of their three season trailers, thus turning it into a four season trailer that can be used in freezing weather.

Thanks in advance!
Mike
19 REPLIES 19

Old-Biscuit
Explorer III
Explorer III
We have a 2007 NUWA 5th wheel that is rated as 4 season
We FTd in it for 7 yrs.
Waste tanks/fresh water tank are enclosed, underbelly is insulated and it does have a Furnace Heat duct down into the tank/valve/piping area

We also have 3 Attic Vents ....front/mid/rear roof areas

We have spent time in Very Cold Temps (-19*F) , Snow (2+ feet overnight) Ice/Sleet ---stayed roasty toasty and NO freezing issues with tanks/lines

Have spent time in High Temps.....110*F+ and stayed nice and cool

Yes some MFGs use '4 Season' as a marketing ploy.
Some actually are 4 season


Need to 'insulate' the tanks/valves/piping and not with Batt Insulation
Need to provide a heat source----duct from furnace works especially when you also have return air ducting back to furnace (airflow circulation)
Enclosed Underbelly...fully sealed ---cracks/crooks/nannies

Upgrade you propane cylinders to dual 30# cylinders

Then it is up to how well the walls/ceiling/floor and slideouts have been insulated
Is it time for your medication or mine?


2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
US NAVY------USS Decatur DDG31

There is a lot more to consider for a 4 season trailer than just dealing with the underbelly.

I was FT for 2 Alberta winters in my 3 season TT, and although an enclosed heated underbelly would have helped, there were a lot of other issues too.

In the minus 30s C, I literally had frost building up on the inside walls in some places. I had to throw a lot of heat at it to keep it liveable. I went through a lot of 30 pounders. Gets expensive.

Water lines that run inside the trailer are typically in the back of closed cabinets. It was a full time fight to keep my water running.
I had to leave cabinet doors open and run electric heaters aimed inside to thaw frozen pipes.

Dump time was no picnic either. I had to leave a radiant heater under my dump pipes for hours just so I could pull the gate valves and empty the tanks.

Another consideration was my propane tanks. In minus 30 temps the furnace ran a lot and the flow would reduce to a slow trickle. A heating pad between the tanks helped a lot.

The windows were caked with ice. Had to block various outside hatches from cold air entering. Had to cover a few windows with foam to try to keep heat in.

The fridge packed it in, too cold, and after many little fixes like a light bulb in the back (Thanks Don for that one) I wound up buying a small bar fridge to hold me over until spring when I pulled the fridge and got it going again.

But!! It was a blast! I enjoyed the challenge of being FT in freezing Alberta winters! Great memories! And a few stories to go with it... :B
2007 GMC 3500 dually ext. cab 4X4 LBZ Dmax/Allison - 2007 Pacific Coachworks Tango 306RLSS
RV Rebuild Website - Site launched Aug 22, 2021 - www.rv-rebuild.com

Sjm9911
Explorer
Explorer
Agreed, tbh, i would never consider a trailer for 4 seasons, unless winter was in the south.
2012 kz spree 220 ks
2020 Silverado 2500
Equalizer ( because i have it)
Formerly a pup owner.

afidel
Explorer II
Explorer II
I don't have a 4 seasons trailer, but if that was a requirement for me I would do my research very carefully. There are a few manufacturers who have actually taken the time, effort, and money to fully test their designs using a cold testing facility, but the vast, vast majority just add a sealed underbelly and a pipe off the furnace and throw a 4 seasons label on the trailer.
2019 Dutchman Kodiak 293RLSL
2015 GMC 1500 Sierra 4x4 5.3 3.42 full bed
Equalizer 10k WDH

Lwiddis
Explorer II
Explorer II
Insulation and enclosing are good but adding furnace ducting with the other two is better.
Winnebago 2101DS TT & 2022 Chevy Silverado 1500 LTZ Z71, WindyNation 300 watt solar-Lossigy 200 AH Lithium battery. Prefer boondocking, USFS, COE, BLM, NPS, TVA, state camps. Bicyclist. 14 yr. Army -11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad