From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Winter RVing
Date: Thu, 18 Oct 2001 04:13:16 -0400

LizWall wrote:

> Can anyone give me the scoop on camping in freezing weather?  We'd love to use
> it to go skiing and fishing this winter.

I love camping in cold weather and do so all winter long.  Nothing
nicer than waking to find one's self snowed in :-)

I've developed several techniques for cold weather camping for my
little Class C.  The plumbing is inside the heated compartment but
none of the tanks are.  I start out by dumping a gallon of
antifreeze into the holding tank.  This is primarily to keep the
valve from freezing.  I've never had the bulk of the tank do
anything more than form a thin skin of ice over the top of the
liquid, something that running a little hot water down the sink will
fix.

I fill my fresh water tank with hot water before we leave.  I've
found that this will carry me two days at least in weather in the
teens.  For longer and/or colder trips, I've rigged up a little
fitting that lets me pipe hot water back into the fresh water tank.
This started out as a short length of hose that would reach from the
sink faucet to the fresh water fill port.  I later hooked in a valve
between a hot water line and the fresh water vent line.  When this
valve is open, the pump circulates water between the fresh water
tank and the water heater.  Eventually the whole fresh water tank
would be heated to the water heater setpoint but I don't let it run
that long.  Running the pump for 15 minutes twice a day does the
trick in even the coldest weather.

My house batteries are in unconditioned space so their capacity
suffers from the cold weather.  I have a Cruising Equipment E-meter
with the battery thermister.  This meter computes the temperature
compensated amp-hours used and amp-hours remaining.  It lets me keep
track of my battery state so I can recharge in time. This E-meter is
probably the best $$$ I've spent on my rig.

To recharge I carry my cordless battery charger (on my web page).
This charger is capable of outputting 150 amps and will charge the
batteries in about 1.5 hours.  A byproduct is that the batteries are
nicely heated.  The heat stays in the battery for most of a day in
still air.  Any of the high capacity intelligent
converter/inverter/chargers and your generator will do the same
thing.  Being a cheapskate, I built my cordless battery charger for
a fraction of what one of these fancy converter/chargers cost.  And
having designed it myself, I made it operate exactly the way I
wanted it to.

When I'm staying in a CG with hookups, I use a Pelonis ceramic disc
heater that I've built in for most of my heat.  The propane heater
kicks in for real cold weather but it doesn't run that much.  I like
the ceramic disc (as opposed to the PTC thermister heaters made by
the same company) because it is completely self-regulating and
cannot get hot enough to set fire to any nearby materials.  The PTC
thermister heaters work on a similar principle but the actual
thermister is small and heats aluminum fins.  The heater has to get
hotter to produce the same heat, hot enough to be dangerous if the
heater is completely blocked.  Space is at a premium in my rig so
the possibility of the heater getting blocked by clothes, shoes, etc
is great.

About the only other bit of advice is make sure your propane tanks
are full.  I have an 80 pound DOT tank on my rig.  I also have a wet
leg (liquid withdrawal) setup on my 500 gallon tank at the
restaurant with which I can fill the MH tank (you can get this setup
from your propane vendor.)  I fill up before every cold weather
trip.  One reason is the obvious - I don't want to encounter bad
weather, get stranded for days and run out of heat.  Another reason
is as important.  If your tanks are low, there is little surface
area to transfer heat into the liquid propane to vaporize it.
Therefore a low tank is more likely to freeze up and be unable to
supply sufficient propane for your heaters.  A full tank transfers
ambient heat over most of the tank's surface.  It may frost but it
won't get cold enough to quit functioning.

From: John De Armond
Newsgroups: rec.outdoors.rv-travel,alt.rv
Subject: Re: 'proper' winterization
Message-ID: <9ha6qukl0nrgo36ffabd8epe9k1b29vbfp@4ax.com>
Date: Tue, 08 Oct 2002 15:03:45 -0400

On Tue, 08 Oct 2002 08:13:23 -0400, "Christopher S. Dargue"
<cdargue@bitstream.com> wrote:

>Is there a preferred, or 'better' method to winterize waterlines in a
>camper? My assumption is there's 2 options:
>
>1) Anti-freeze in the water lines.
>
>2) Blow the lines out with a compressor.
>
>The only 'con' I can think of is using the anti-freeze it takes alot of
>flushing in the spring to remove the anti-freeze form the lines.

The biggest "con" and the reason I wouldn't dream of using the pink stuff, is
that once you winterize you then have an excuse not to use your rig through
the winter.  I use my rig almost every weekend through the winter so my
winterization involves opening the low point valves, draining the fresh water
tank and blowing the lines.

The problem people have with blowing the lines is almost always related to the
volume of air available.  Those little shraeder valve adapters just won't cut
it.  I made up a rig involving a high volume pressure regulator and a male
garden hose fitting that lets me push max volume of air at 40 psi from my
large stationary compressor.  Search google for the details.

I like to dry camp in very cold weather.  I've worked up a couple of tricks.
First off, I put a gallon or two of pink stuff in the holding tank to keep it
from freezing.  This works without the power a tank heater would require.
Second, I've made up some plumbing and a valve that lets me run water from the
water heater back into the fresh water tank.  This lets me use the water
heater to heat the water in the fresh water tank.  simply open the valve, turn
on the pump and wait a little while.  I find that if I fill my fresh water
tank with hot water from the water tap at the start of the trip, the tank will
stay above freezing for a day.  Then once or twice a day bring the temperature
in the fresh water tank up to 100-120 degrees.

I've stayed the better part of a week that way, snowed in on top of a
mountain, loving every minute of it. Toward the end I WAS melting snow to
refill my water tank and WAS making yellow snow as it worked its way back out
but that was part of the fun.  Never a single freeze problem.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: 'proper' winterization
Message-ID: <0bebqug4mi8idqbc7cu929c1sru7neagtn@4ax.com>
Date: Thu, 10 Oct 2002 13:34:34 -0400

On 09 Oct 2002 22:22:47 GMT, rvnnow@aol.com (RVnNOW) wrote:

>>>  I made up a rig involving a high volume pressure regulator and a male
>>>garden hose fitting that lets me push max volume of air at 40 psi from my
>>>large stationary compressor.
>>
>
>Keep in mind that Neon is in Cleveland Tennessee. He doesn't know what real
>winter is.

Got down to 6 last year. Twas a record.  I have the photo of the digital
thermometer.  That close enough to winter?

Our fake engineering experts to the contrary, if one pushes sufficient volume
through the plumbing the air will be DRY in a minute or two.  That's good
enough regardless of the temperature.  A shraeder adapter and a 12 volt air
compressor won't do it.  My setup will.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Winter Is Comming, Winterize Early
Date: Thu, 14 Oct 2004 15:45:38 -0400
Message-ID: <j0ltm09tg8vgrgoh0sudok5d5dmj84fvjk@4ax.com>

On Thu, 14 Oct 2004 13:24:43 -0400, "Kevin Gale" <kevint1@nhwoods.net>
wrote:

>The trick I use is an old one. I just put a drop light with an incandescent
>bulb in the compartment with the pump and fill. I say incandescent since so
>many people now use high efficiency fluorescents, and in this case you want
>the inefficiency which shows up as heat!
>
>For my unit a 100 watt bulb works down to single digits Fahrenheit, haven't
>tested below that.

What that means is that your rig is set up to operate to single digit
temperature.

100 watts is only 341 BTU/hr.  That is a tiny, insignificant amount of
heat that really doesn't do anything to help.

An experience with my mountain cabin's wellhouse opened my eyes (and made
me do the math).  Following conventional wisdom, we'd always left a 300
watt bulb on in the wellhouse.  In addition to the heat tape, of course.

One year I forgot to check the house and we went all winter with a burned
out bulb.  No problems.  the heat tape was what worked.

If I had an  unheated space in my RV, I'd install a conventional small
portable heater along with a thermostat that I could set to, say, 40 or 45
deg.  The whole setup would probably use less power than a light bulb
because it would run only when needed.  Plus it would actually protect
from freezing.

All my plumbing is inside conditioned spaces so all I do is open the
appropriate cabinet doors to make sure warm air gets to the pipes.  Only
my tank is in the open.  To address that problem, I've installed a valve
that routes hot water back to the fresh water tank.  I have one of those
el-cheapo indoor/outdoor thermometers installed with the sensing element
down in the water tank.

When I see that the tank is nearing freezing I simply open the valve and
allow the pump to circulate water between the heater and tank, heating the
whole inventory.  I let the water get up to the 90-100 deg range which is
good to keep the tank from freezing for about a day even in the worst
weather we see around here.

I've been using this system for about 3 years now and it has worked
perfectly.  I'm thinking about adding a little controller and solenoid
valve to make the system automatic.

For my wastewater tank (I only have one combined black/grey tank) after I
dump, I pour in a gallon of RV antifreeze.  This settles down in the valve
and discharge piping and protects it from freezing.

Excrement freezes at a lower temperature than pure water so it has to get
pretty cold to freeze.  If the tank does freeze, all I do is run several
gallons of hot water into the tank a little while before dumping.  I can
see thru the toilet into the tank and can see that this completely thaws
the tank.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Winterization logic/Pink stuff (why?)
Date: Sun, 21 Nov 2004 22:24:08 -0500
Message-ID: <dmm2q05fbejffj80faiqn79lvo93h92673@4ax.com>

On Sun, 21 Nov 2004 05:36:38 -0500, "Steve Wolf" <news@w8iz.com> wrote:

>In preparation for a camping trip, I took about five minutes flushing the
>pink stuff out of my pump.  The remaining lines had been simply drained.  I
>was up and running in seven or eight minutes.
>
>It might make more sense for you folks to figure out where water is pooling
>in your systems and install drains at those locations.  It beats the heck
>out of filling the pipes with pink.  I suppose if you are laid up all winter
>it is easier to just fill the system than engineer it properly.  If you are
>camping all winter, the pink fill would be significantly more trouble.
>
>Steve
>www.wolfswords.com under the motorhome and winter camping link
>

Right you are.  I get a kick out of these annual winterization arguments.
If they spent half as much time making their systems right as they do
arguing...

Itasca was nice enough to put low point drains in my rig.  I drain the
fresh water tank, let the pump pull enough air to quit gurgling and then
blow out the lines with air.  Not one of those tire valve adapters they
sell at the RV store.  A setup I made that supplies high volume air at 40
psi to the city water inlet.  I let that blow until the gurgling stops,
indicating that ALL the water is gone.  A gallon of pink stuff down the
toilet to protect the dump valve from freezing and I'm done.  I'd be
shocked if the process took even 10 minutes.

When I'm ready to go camping next, I fill the tank, close the low point
drains and let the pump prime.  No flushing, no futzing around trying to
get the taste of the antifreeze out of the system.  Just fill and go.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Winterization logic/Pink stuff (why?)
Date: Sun, 21 Nov 2004 22:57:52 -0500
Message-ID: <poo2q0566tpchiakv49j4fsbm0urrbdhok@4ax.com>

On Sun, 21 Nov 2004 21:36:56 GMT, "Ed" <edgar88@FIXatt.net> wrote:


>Maybe not in this thread but in the past one poster did state that he let
>his tanks freeze and never had a problem.

Probably me.  I let my blackwater tank freeze when I'm camping.  I can see
the ice through the toilet.  However.  I don't just arbitrarily let it
freeze.  After each dump in the winter I pour in enough pink stuff to fill
the dump valve and the short pipe leading to it.  All the plumbing is
inside in conditioned spaces.  Nothing except the tank itself and the dump
valve are exposed to the cold.

I've been doing this for years without any problems at all.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Best space heater for winter?
Date: Sun, 25 Sep 2005 03:29:25 -0400
Message-ID: <20kcj1luh5s6agq3dnk8i189f6ao3sm8hc@4ax.com>

On Sun, 25 Sep 2005 00:31:32 -0400, "Steve Wolf" <news@w8iz.com>
wrote:


>You might consider the way Winnebago sets up their motorhomes.  First, both
>ahead of and after the pump are three way valves that allow you to
>(effectively) take the pump out of the system.  You can run antifreeze only
>through the pump.  Next, there are valves at the lowest point in the system
>that allows proper drainage.  There are no low points.  You antifreeze the
>pump, open the valves, drain the water, and walk away.  It takes about 15
>minutes.

As you probably know, Itasca is Winny's upscale line so no surprise
that mine has all that hardware too.  I don't use it normally because
I hate fooling with the pink stuff and I want the rig ready to roll on
a moment's notice.  When it's very cold out, I keep the fresh water
tank drained.  When I'm ready to go, I fill the tank with hot water
and away we go. That holds me for the first 24 hours.  I already have
food and clothes in the rig so the ET from deciding to go to pulling
out is probably 15 minutes.  I'd hate to have to double that by having
to flush the pink sh*t out of the pump.

>I added a valve to the hot water tank to allow it to dump overboard.  I have
>an electric element where the other valve had been.

I broke down last year and got a new direct ignition/electric water
heater.  Designed that way from the factory, the unit uses a standard
screw-in water heater element rather than a Hott Rod type affair. Very
nice.  This one didn't have a drain cock but does have an anode at the
bottom of the tank so I installed a street Tee, inserted the anode
into the straight part of the tee and a ball valve on the side leg.
Now I can drain it fast.

I normally leave the electric element on in cold weather to prevent
freezing.  With the old heater, I put a ball valve in place of the
radiator drain cock on the bottom and drilled and tapped the side of
the safety valve below the seat on top for a small ball valve for air
bleed.  With both valves open, the tank would drain in under 5
minutes.  I'm probably going to have to do the safety valve mod to the
new one too, as it doesn't drain well at all unless the safety is held
open.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Best space heater for winter?
Date: Mon, 26 Sep 2005 03:23:45 -0400
Message-ID: <ha8fj15s78d3s8a10ue394b1r807dg0172@4ax.com>

On Sun, 25 Sep 2005 09:19:21 -0700, Pegleg <chap2003@hotmail.com>
wrote:

>On 25 Sep 2005 06:39:41 -0700, "CMaster" <TerryBullard@TerryBullard.com>
>wrote:
>The radiant
>>heaters or for that matter any space heater will keep you warm but they
>>will not prevent a freeze up here in Ferndale. The NE wind freezes you
>>up sideways through the walls even if you have all your access doors
>>open and it's a +70 inside.
>
>Something is very contradictory here...if it is 70° inside there will be
>no freeze up except possibly holding tanks/valves which can be protected
>with the pink stuff.  You seem a bit prone to exaggeration Terry!

No, not at all.  In that kind of weather, the room can be at 70
degrees while the walls inside cabinets are far below freezing.  water
tubing in contact with those walls and floors will freeze.  It doesn't
take 70 below either.  Single digit weather is more than enough for
many rigs.

Since my rig's frame is made of aluminum (very thermally conductive),
one of the first things I did to get ready for cold weather camping
was to lift the water tubing away from the frame and insulate it with
that black foam water line insulation.

I have seen frost on the exposed frame bulkheads in my rig and I've
never had the opportunity to camp in below zero weather.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Best space heater for winter?
Date: Tue, 27 Sep 2005 14:11:02 -0400
Message-ID: <en1jj1l79hmbtdhlkcfd9004m3lidagsvt@4ax.com>

On Tue, 27 Sep 2005 08:41:47 -0700, "Ben Hogland"
<benhogland@hotmail.com> wrote:


>This entire thread about wind-chill is all very interesting but whether
>or not wind-chill is important to an RVer is really the question. If you
>are trying to maintain a certain temp above freezing inside the RV and
>around the pipes, the answer is yes. The amount of energy required to
>maintain a temp above freezing will be more if the wind-chill outside
>is -50 vs 31. This is, of course, if the real temp is below freezing but
>even when above freezing, if you are trying to maintain, say, 70 degrees
>inside the RV, the lower the wind-chill, the more energy needed to
>maintain the heat inside.

The answer to that is no, it doesn't.  Wind chill is strictly an
attempt to quantify the product of temperature and wind velocity.

In a decently insulated RV, the outside skin will be essentially at
the outside temperature or a few degrees above.  Wind blowing across a
surface at ambient temperature has no effect or in the case of the
skin being a little warmer in still air, not enough to matter.

Glass is another matter.  Moving air across glass will make some
difference.  If one has proper window coverings in place, the
difference will be small.

If your RV has defects that allow air infiltration then if the wind
blows in the right (wrong?) direction then it will matter but that's
too specific a situation to generalize.

There are some other minor considerations such as the water heater. If
it isn't on and the wind is blowing just right, there might be an
added amount of cold air circulation through the flame tube.  Of no
consequence to the comfort level, at least until the water heater
freezes and one can't take a shower!

In my case, with a well insulated rig and thanks to Mr Handy Foam in a
can, no air infiltration to speak of, all the wind does is gently rock
me to sleep.  I've camped in blizzards on top of local mountains where
the snow has been blowing horizontal and still been warm and
comfortable inside the rig.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Best space heater for winter?
Date: Tue, 27 Sep 2005 14:19:26 -0400
Message-ID: <313jj196n15h907ueot7bjbkt2inbifkt5@4ax.com>

On Tue, 27 Sep 2005 15:09:20 GMT, zeromedic@go.com (zero) wrote:


>To be absolutely accurate, relative humidity Does affect wind chill.

To be absolutely accurate, humidity has no effect on Wind Chill
(notice the capital letters, as Wind Chill is the proper name given to
the model of perceived cold developed by the NWS) as was noted in an
NWS quote earlier in this thread.

>But generally, most people who are concerned about wind chill factor only
>care when the numbers are the numbers are  below 20F, and mostly
>concerned when the number is minus anything F.
>
>At these temperatures, the difference between 100% Rh and 0%  Rh is
>almost nil as far as perceived (human skin) temperature feels.

Based on notes in my journal that I've kept over the last several
years because I'm interested in this topic, humidity DOES indeed have
a large effect on perceived cold - but only under still conditions.  I
can be in mid-20s weather in my shirt sleeves and be comfortable when
the humidity is high, such as immediately after fresh snow.  At the
same temperature and low humidity I need a rather hefty jacket to be
comfortable.

Once the air starts moving, humidity has little to no effect on my
comfort.  The NWS has noticed the same thing.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Flushing Water System
Date: Tue, 18 Sep 2007 01:14:26 -0400
Message-ID: <v4nue398r765ua5pj2u0ivdf5uj08t5t8m@4ax.com>

On Mon, 17 Sep 2007 22:31:57 -0500, "Advocate54" <llafrin@hotmail.com> wrote:


>"Okie" <okie7597@yahoo.com> wrote in message
>news:1190078920.884951.226890@n39g2000hsh.googlegroups.com...
>>I am inspecting a used trailer for possible purchase.  I was told the
>> water system had been "winterized" and today, when I opened the drain
>> valve, out came ethylene glycol.  My question is, will any amount of
>> flushing make this water system safe?
>>
>If it is indeed ethylene glycol in the water tank, I wouldn't buy the rig.
>He has poisoned the system.

Oh bullshit!  EG does no harm and washes out easily.  Besides it isn't toxic per se.
Before you think you know more than me, go look it up.  It is the metabolite of EG,
methanol, that is toxic.  What EG that isn't metabolized is excreted in the urine.
That's why the standard treatment for EG ingestion is ethanol.  That's right, booze.
They get you really drunk on IV ethanol.  The body preferentially metabolizes ethanol
and that gives the kidneys time to excrete the EG before it gets metabolized into
methanol.

What that means is that traces of EG are perfectly harmless. It's not itself toxic
and it doesn't accumulate. Some gets excreted and some gets metabolized.  There must
be a certain concentration of methanol in the blood to do harm and that requires a
pretty good dose of PG.  The body routinely and daily handles small quantities of
methanol.  Any fermented product has a certain amount of methanol in it.  Just the
way yeast works.  If you drink then you drink some methanol.

If the system really does have EG in it (probably not, probably the more usual RV
propylene glycol) then all that is necessary is to flush the system.  BFD.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: used travel trailer for winter use
Date: Sat, 29 Oct 2005 01:41:31 -0400
Message-ID: <1v06m1leli6929bfj6e0dnp5fl8dvr92fn@4ax.com>

On Sat, 29 Oct 2005 00:21:13 GMT, Diane <diane@baywing.net> wrote:

>Hi BILL P. and Just Dog.
>
>Thank you for your suggestions. We never said it would be easy and we
>don't expect it to be.
>
>I will pass along the idea of a contractor's trailer rather than the
>travel trailer - we are actually looking at renting a contractor's
>office trailer - no plumbling just heated and lighted space for extra
>work room.

I'd forget the contractor's trailer.  I've spent way too many cold
days in one of those things!

>
>I think she thought the travel trailer would be of more use in the long
>run. Also one of the reasons for the non-5th wheel. Since we don't own a
>truck and will be leasing one we thought the 5th wheel would complicate
>things. The last time I looked (10 years ago) there were various types
>of 5th wheel hitches, but the tow-behind model was more standard from
>truck to trunk.

I agree.

As you're learning, there are a number of folks here who've never
attempted doing what you're going to do but they have advice anyway.
Unfortunately you have to do some heavy filtering.

I noticed that Steve Wolf jumped in under another subject line.  Among
those who post here frequently, it seems that he and I are among the
only ones who actually camp in the winter.  My area here in the
Tennessee mountains gets down into the single digits.  Steve's in
Ohio, below zero.  We both camp all winter long, have a ball and have
no problems.

Steve has a good web site and I've posted extensively on my
techniques.  You might want to google on my name (neon_john) and
"winter".

Since you have power and will be in a fixed location, you have many
advantages over those of us who actually go out in the woods to camp.

First off, you can just about prevent any freezing problems with
proper heat tracing.  Heat tape the fresh water coming in and the
sewer going out.  Insulate over the heat tape.  I HIGHLY recommend
spending the extra money on the industrial type self-regulating tape.
This consists of a semi-conductive plastic that varies its heat output
according to the temperature at each point on the tape.  This kind of
tape won't develop hotspots and damage plastic plumbing.  This is
especially important when tracing empty piping such as the sewer
piping.  Omega Engineering, Watlow and a few other companies will help
you with the application engineering.

You can get adhesive mounted silicone heater pads from Omega
Engineering, Watlow and others.  Apply suitable wattage heaters to the
bottom of the tanks.  Install a wind skirt to keep out moving air and
optionally, apply some styrofoam sheeting against the tanks.  Get the
kind of heater pad that is self-regulating so that you don't have to
worry about overheating.

Even though I use antifreeze as protection for my black water tank, I
don't recommend it in your situation.  You're going to be in one spot
for a long time.  You won't want the hassles of constantly maintaining
the antifreeze concentration.  You want the head and sinks to work
without thought just like they do at home.

You'll not want to leave the dump valve open, for crud and stuff will
build up in the tank.  You'll want to fill the tank and dump it when
full.  An electrically operated dump valve that can be operated from
the warm area is VERY nice.

If the hot and cold water plumbing lays on the floor or is against the
outside wall (most are), get some foam pipe insulation from the
hardware store, lift up the tubing and encase it in insulation.  If it
remains in contact with a cold surface, it will freeze via conduction
even if the ambient is above freezing.

I leave my cabinet doors open in very cold weather so that heat can
circulate to keep the plumbing warm.  If the doors being open will get
in your way, cut some vent holes in the cabinet and install a fan (a
muffin fan will do) to circulate air within closes spaces.

Bring in additional wiring over and above the 30 amp service the RV
comes with.  Bring in at least 50 amp, 240 volts.  You can bring that
in through a vent or a hole drilled in the floor or something and
leave outlet boxes laying on the floor.  These are to hook electric
heaters to.  Electric heat is much easier to deal with in a remote
location than propane if you have reliable power.  Remove the extra
wiring when you don't need it.

I'd have a 250 gallon propane tank set on site if you can't wire in
the electric heat.  Even with the electric heat, I'd have at least a
couple of 100 lb tanks, more if you can afford them.  A blizzard with
the power off is not the time to need a tank refill.  Most propane
companies will supply the tanks without charge if you have them filled
a specified number of times a year.  You will :-)

If you're bunking several people, make sure the water heater is large
enough and has a sufficiently powerful electric element in addition to
the gas heat.  In really cold weather you might want to disable the
gas and pack the outside spaces of the heater with fiberglass
insulation to cut down on heat loss and speed the recovery.

A heater that comes from the factory with an electric element uses a
standard water heater element.  You can change that out from a 120
volt element to a 240 volt element and heat water 4X as fast.
Important when several dirty and cold people are waiting on the
shower!

Make sure you get a full kitchen with oven.  Some RVs are now being
equipped with convection microwaves and no ovens.  Frankly, they don't
do so hot for real baking.  As you probably know, the colder it gets,
the more hearty food you'll crave and there's nothing like baked food
to satisfy that itch.

A tabletop electric oven is also recommended.  When you have to have
the RV pent up tight in very cold weather, the gas oven will kick out
enough moisture to make everything drippy.  The electric oven will be
a little slower but at least everything won't get soggy.

The lightly insulated walls will collect condensation from your
breath, bathing and cooking.  If your bunk is up against the wall like
most are, the moisture will dampen your linens.  My solution to that
is to tack up a quilted moving pad against the wall so that it
separates my linens from the wall.   The pad is both absorbent and
insulating.

Whether I went with a bunkhouse model would depend on how much waking
time I'd expect to spend in the thing.  If you think you'll be stuck
in there for days at a time by weather, then I'd not do it.  The
bunkhouse models tend to have very little other furniture so that
you'd end up spending your time in your bunk.  Cabin fever develops
rapidly under those conditions.  You, of course, need to think down
the road past just this winter.

I can't recommend a specific brand of trailer because I'm a motorhome
guy.  If I were in your shoes, I'd search for an RV dealer located in
one of the cold areas, say, Minnesota, ring him up and ask for his
advice.  I do know that there are all-weather rigs made where the
plumbing and so on is in heated spaces but I don't know any brands.

Lastly, unless there is a program requirement to buy new, look at
used.  RVs tend to dump half their value when they roll off the lot.
You can stretch your budget much farther and maybe even buy a second
unit to avoid the sardine can effect by buying used.

John