3 Cold Weather Tips for a Diesel RV

I’m shivering like a mobster in a tax collector’s office.

It’s 21 degrees in Austin and dropping to 16 degrees tonight! Ok, ok, I get it. All you South Dakota folks and Canadians out there are just snickering at us. But hey, anytime you have to open the refrigerator to heat the house (or the RV), it’s too darn cold!

So here’s the story. Brittany and I bought our brand “new to us” RV on January 2nd. On the 3rd, we took it to an outdoor storage facility and parked it. Our intentions were to clean and prep it for full-timing by February 22nd when our lease expires.

It was a good plan. A solid plan. One that worked with our timeline. What could go wrong?

Then came the cold weather report. Immediately I started getting texts and messages from quite a few people with cold weather tips for a diesel RV.

Typical texts went something like this:

“Looks like a very hard freeze Monday night. I suggest you wrap the faucets and make sure the pipes are drained well. May even want to leave the faucets turned on to prevent valves from breaking. I’d hate for you to incur a costly repair due to the cold.”

Yikes! Of course we hadn’t thought of this or planned for it. But it tossed us into a whirlwind of information gathering, wisdom seeking and Internet surfing.

Cold Weather Tips for a Diesel RV

Here are 3 cold weather tips for a diesel RV that we gathered from our research.

1. Protect Your Pipes

Pipes burst. This sucks and they are really expensive to fix. So to prevent this…

If you aren’t going to be using the RV:

• Drain all the water from your pipes.
• Blow out the pipes with an air compressor.
• Wrap all faucets for extra insulation.
• Open the valves on all faucet fixtures.
• Shut off the valve to the water heater.
• Cover the water pump with an electric heating pad.
• Run a space heater inside the unit.
• Open the cabinet doors anywhere there are pipes.

This seemed incredibly complicated to us newbies and, like first-time parents, we wanted to be extra careful with our baby. We didn’t have power at our storage unit, so we couldn’t do some of these things that sounded really important.

We talked with a few experts. They said the easiest way to protect the unit if we didn’t have power was to take our RV out and plug it in somewhere.

So with four days’ ownership of the rig, we were off to a State Park. Nothing like jumping in head first.

Now, if you are actively using the RV or have power:

• Fill your fresh water tank and disconnect from the water source. (The hose is more likely to freeze than the tanks.)
• Use your coach heater early in the day, before it gets extremely cold, and keep all doors and windows closed.
• Run a space heater. Be mindful that they guzzle electricity. Ours is 1500 Watts and draws 12.5 amps.
• Open all cabinets where pipes are exposed.
• Drip all faucets at night. Read: drip (not trickle).
• If you have a large RV like we do, close any doors that separate spaces. Run the space heater in the room you are in and the coach heater in the other half of the rig. Close all vents in the room you’re in if the system is ducted. That way, all of the heat from the heater that’s running will keep the other room from getting too cold.

2. Protect Your Fuel Tanks, Fuel Lines and Fuel Filter

Diesel starts to gel and can solidify when it gets really cold. Not a good thing. Here’s why gelling happens:

• Diesel contains paraffin wax. When the temps hit freezing, the wax crystalizes.
• When the temperature hits 15 degrees the wax solidifies, the diesel gels and clogs the tank, lines and fuel filter.

Diesel stabilizer is a product you can buy and add to your tank. In effect, the stabilizer will prevent the diesel from gelling.

We’ve heard that old school folks will use kerosene. What the what? We’re definitely not old school, so not going there. But hey, if you’ve got those kind of RV chops, our hats are off to you.

3. Timing is Everything When Starting a Cold Diesel Engine

Diesel engines don’t like to start cold. And they can be finicky.

• Diesel engines take a ton of power to crank up, due to air compression ratios. This takes a lot of battery power.
• Diesel rigs generally have larger batteries with larger battery cables and heavy duty starters.
• Batteries generally don’t do well in cold weather. They lose power.
• Gas engines use a spark to ignite fuel that is already in a cylinder. Diesels don’t work this way. Instead, diesel engines heat air via compression and then inject fuel into the heated air, which starts the diesel burning instantly.
• Glow plugs are little mini red-hot heaters in diesel engines which only activate for a short moment. If that moment is lost, you lose the benefit of the glow plug.
• On most big diesel rigs, you’ll have a light on the dash that says “Wait to Start” or “Glow Plug.” Pay attention to it. You want to start up the engine the moment this light goes out on your dashboard.
• Timing is everything. As soon as the glow plugs heat and the light goes out, crank that baby over. If you miss your opportunity, wait and let the system recycle.
• Also, if you have an engine block heater, make sure that it’s turned on and leave it on. It’s basically like an electric warmer for the engine block. A great thing to have, but no good if you don’t use it.

So there you have it! 3 cold weather tips for a diesel RV, and we’re only on the first trip of our adventure.

I’d like to thank the irv2 forums, Steve DiRocco, Mark Richardson, Truckers Report, Speed Guide and every other person and site we gleaned this info from!

Got any other cold weather tips for a diesel RV? Comment below. We’re just learning ourselves and would love to learn more!

-Eric