It will only take about 24 hours of below-freezing temperatures (lower than 32 degrees Fahrenheit) for the pipes to freeze in your RV. Since the average trip lasts a great deal longer than that, you should definitely take action ahead of time.
Insulation is key to keeping an RV warm in the winter. Insulate windows with plastic on both the outside and the inside. Then use thermal drapes, especially on any north-facing windows, or use quilted or polar fleece material; tack the material to the walls with velcro if possible to prevent drafts.
As an example, the -50°F antifreeze has a freeze point of +20°F while the -100°F antifreeze has a freeze point of about -20°F. However, as the temperature drops the solution begins to solidify and expand, putting pressure on pipes that can lead to damage.
If your unit is low on refrigerant that can cause the unit to freeze up too. If the freezing is new and all the other variables are the same you may have a refrigerant leak.
Your air conditioner might take anywhere from an hour to more than a day to completely defrost. It's important to catch it early to prevent further damage to your unit—and, of course, so you're without cool air for the shortest amount of time possible.
To put it simply, an RV air conditioner can run for as long as it is connected to a source of power. If your camper is connected to residential shore power or an RV park power hookup, your AC will have no problem running all day and night. The same holds true if your source of power is a generator.
Most RVers simply drain the fresh water tank and bypass it. Should I put RV antifreeze in my black tank? The same advice applies to your black and gray tanks—there's no harm in adding it to either.
Camper pipes can start to freeze at 0°C (32°F). If your camper isn't warm enough or the pipes aren't covered properly, they can freeze even if it's just a bit colder than usual outside. Remember, every camper is different, so it's good to check yours as it gets cold.
Lower Freezing Point
Coolant with a 50/50 mixture has a freezing point of -35 degrees Fahrenheit. Further, a 70/30 mixture of antifreeze and water drops the freezing point lower to -84 degrees Fahrenheit.
Tanks that are exposed to outside temperatures need some kind of insulation to keep them from freezing. Prolonged temperatures below freezing will eventually freeze a tank, either preventing you from dumping or preventing you from getting the fresh water you need.
Can pipes freeze in one night? As surprising as it might sounds, HVAC expert Josh Rudin says, 'Water pipes with cold water in them experiencing freezing temperatures in the evening can absolutely freeze and burst all in one evening.
Heat the RV's interior
The warmer your RV is as a whole, the less likely your pipes are to freeze. Adjusting the interior temperature of the RV to keep it consistently warm will help the pipes stay warm as well.
The most precise answer we can give you is when the temperatures outside hit between -20 degrees and -30 degrees Fahrenheit. It is extremely difficult to bode well in an RV in this climate.
Water pipes burst because the water inside them expands as it gets close to freezing, and this causes an increase in pressure inside the pipe. When the pressure gets too high for the pipe to contain, it ruptures. This expansion phenomenon seems natural, but interestingly, it is a chemical anomaly.
The key element to RV winterization is preventing your water pipes and lines from freezing or bursting in the winter months. If you live in an area where your RV will encounter temperatures near or below freezing for more than 24 hours, chances are you'll need to winterize your rig.
Install a heating blanket over the frozen tank. Place a portable propane heater under the RV to thaw both tanks and pipes. Apply RV skirting to trap heat underneath and block cold air. Use RV antifreeze in your wastewater tanks and drain lines to prevent further freezing and assist in thawing.
Add Tank Insulation
If you don't want your water to freeze during winter, make sure to insulate your tank properly. A good way to do this is by using an insulating material that covers the tank on all sides including the top. This will prevent heat from escaping and keep the tank warm enough so that it doesn't freeze.
ADD ANTIFREEZE
Move on to the next faucet and the next until you've hit all faucets throughout your RV. Also make sure you do this with your showers, both inside and out. Flush the toilet until you see antifreeze, and then pour a cup of antifreeze down each drain (including the toilet).
Cleaning your black water holding tank is best done when you're fully hooked up and have both a water and sewer connection. Avoid using bleach or antifreeze for your deep clean, as both of these can dry out rubber seals and ultimately ruin your sewage system.
To answer your question directly windshield washer fluid is good to -20 degrees and is less than 1/2 the price of RV antifreeze.
The condensed humidity or moisture can actually freeze on the evaporator coil, limiting the coil's ability to chill and expel the cooled air back into the room. This makes your system work in overdrive to keep the inside of your RV cool, which causes ice build-up.
RV air conditioners are notorious for being the largest power consumers in modern RVs. When running they can draw between 700 watts (for a 10,000 BTU unit) all the way up to 1,500 watts (for a 15,000 BTU unit). In fact, at startup they can draw more than double that amount of power.