Heated Mattress Pad

JRscooby wrote:

JKJavelin wrote:
. The only negative is it heats slower than an electric blanket.

This may or may not be true. And if true, may or may not be a issue. I know that in my truck, my camper, or house, it has never been a issue for me. AFAIK, the real difference is you use one over, the other under you. Somebody told me heat goes up.

Hot/heated air does indeed go up.

Radiant heat radiates up, down, sideways ... wherever the surface(s) of the source(s) are pointing.

The hot wires in either a mattress pad or an electric blanket shoot out their radiant heat all around the wires up, down, sideways, etc.. I know ... as I've used electric blankets on top of me for decades, and they in fact do warm me just fine when lying under the bottom side of the blanket. ;)

P.S. Now - for the real challenge - how many of us RV'ers use electric mattress pads or blankets when camping without hookups?

Phil,

I've been using electric blankets for some years without hookups.

Since the late 1980's we have been using either an electric mattress pad or a heated blanket in all our RV's when not on connected to shorepower. Makes zero difference to us or many others as we and most others also had/have a very capable inverter and an adequate number of batteries/amps to suppkly the DC power needed by the inverter.

Never once have we drawn the batteries below 50% charge yet in any month of the year. If you have large enough wire size going from the vehicle to the RV batteries/converter charger, the alternator output will recharge the batteries fast. Too small of a wire size (gauge) acts as a choke and the recharge takes many to very many hours to recharge them. Can't stress that strong enough! Also having a 1000 watt + generator and a 25-40 amp battery charger will do the job well enough too.

Some use solar but you still need enough amps output from adequate sunshine hours to be able to recharge adequately. Clouds blocking the sun and trees/leaves blocking the sun are a big issue in the eastern half of the USA as trees are almost everywhere and especially in popular CG's, state forests, national forests, national parks, etc.

An electric mattress pad or blanket doesn't draw that much current and it only draws current when heat is actually called for. We usually see 25% to 30% of an hour.

I have used electric blankets or mattress pads for many years when needed, just not with an inflated air mattress

If we were to start using a heated blanket or mattress pad on our RV trips, we'd skip the efficiency loss of an inverter and plug them directly into a 12 volt recepticle coming from the coach batteries ... as can be done with these:
https://www.12volt-travel.com/12-volt-electric-blankets-c-90.html

Over many years I have tried out various 12v appliances
From bottle warmers to instant water heaters, to defroster / heaters

Fans and radios and tv worked
Everything that produced heat was a big Flop

I know there are travel blankets and such things
And some people have had good experience with them
But not me
I'll stick with 120vac items on an inverter
They use more power and there is conversion losses
But they do the job

MrWizard wrote:
Over many years I have tried out various 12v appliances
From bottle warmers to instant water heaters, to defroster / heaters

Fans and radios and tv worked
Everything that produced heat was a big Flop

I know there are travel blankets and such things
And some people have had good experience with them
But not me
I'll stick with 120vac items on an inverter
They use more power and there is conversion losses
But they do the job

As I understand it, an electric blanket consumes around 80 watts. This equates to only around 7 amps at 12 volts (when it's "on" ... but they cycle continuously, so AH draw averages less). What this means is that a 12 volt electric blanket (and mattress pad) should work far better than the 12 volt appliances you are referring to that require far greater 12 volt currents in an attempt to match the wattages of similar 120V AC powered household appliances.

A 12 volt powered electric blanket/mattress pad should functiton as good in an RV as a 40-50 watt TV functions in an RV. Inverter losses would thus be eliminated when using them night after night in an RV for comfortable drycamp sleeping so as to be able to maintain lower coach interior air temperatures ... and thus saving overall energy.

But you have to have 12v wiring going to the use area that will maintain the voltage needed at the amps needed
And many of these products only supply the stated heat level
When the engine is running and the alternator is supplying 13+ volts
What might be practical in a van
Is not so useful in a larger RV, like my 36ft rear bedroom class A
The amount of heat desired/needed various with the individual
I sometimes use a heat pad on my back before going to sleep
But again this is my home, not for my weekend use to play in the snow

The problem with 12 volt, which MrWizard has nibbled around is often voltage drop.

The "power" drops by the square of the voltage.

13.6 x 13.6 =~ 185

11.9 x 11.9 =~142

That's approximately a 23% drop in power. So now the effective wattage has dropped a heck of a lot. 80 watts x 77% =~ 62 watts.

The higher the wattage on the device the worst the results become, as the voltage drop is larger and larger.

That said, I've had good luck with a 12 volt 7 amp electric blanket. It is "old school" and doesn't have a timer on it to shut it off.

I have now moved to a mattress pad (from Aldi's) as they were being sold for just $65 USD last year. I love it--but wish I did not have to run the inverter.

Many hopes for a wonderful 2020 to all.

we’ve been on the road for just over a week now and we love the heated mattress pad! my side is at ‘4’, hers us at ‘6’. i have it between the bottom sheet and another mattress pad. we don’t feel the wires...very comfortable. a big thumbs up! :B