Electrowarmth 12 volt mattress heater

[Ned5555]

I’ve only seen members mention this type of product in passing, so figured it deserved a more thorough write-up for people looking for heating solutions this winter.

For background, our van is a 2014 Sprinter with penthouse. It was designed for 3-season camping in moderate climates, so there is no coach heat or air conditioning. As an all-electric system, it does have the extra 4D battery bringing the total capacity to 400 amp hours. While a 110 volt ceramic heater helps while docked at a campground, I had been looking for ways to take advantage of the big battery bank to help stay warm while boondocking.

There are a bevy of 12 volt heated blanket options available online and at truck stops. However they seem to vary in quality and most have a safety timer of just an hour or two before shutting off. That’s hardly ideal for sleeping through the night.

During the search I came across the Electrowarmth mattress pad heater. It’s marketed as a “bunk warmer” for truckers with a list price of more than $100 – putting it at the top edge of the market. But their design makes sense. Since heat rises, you want the heating element under you instead of a blanket on top of you that dissipates heat into the air.



The pad only comes in a Twin 36’’x60’’ size, which you can see easily fits on the penthouse mattress. It’s generous for one person, but isn't very roomy for two. Additionally, the coils don’t run to the outer edge, so most heat radiates near the center of the product.



The instructions warn this is not an instant heater – don’t think it’s faulty because you’re not toasty in five minutes. Instead it’s a very gradual build, and works even better if you can turn it on 30 or 60 minutes before bedtime. I set the thermostat to “7” while making up the bed and the blankets were luxuriously warm when I came back from the campfire. A “3” setting was perfect overnight with temperatures the 40s. The penthouse bed stayed warm but never uncomfortably hot.



Power usage is noticeable, but far lower than any type of space heater. The pad has a generous 12v power cord, which I ran to the outlet downstairs. The maximum draw appears to be 7 amps, though runs much lower once warmed up. After that night in the 40s with the fridge also running, the Magnum meter showed my battery bank dropping from 99% to 87%. I imagine the toll would be worse in colder weather – when the pad runs extra hard and battery performance is degraded.

Overall I think the heated mattress pad is a solid addition for cold weather camping, especially if you have no other built-in heat source. The Electrowarmth is American-made with a 1 year warranty, designed for people who have no choice but to sleep in their vehicles.