Heated blankets away from the bedroom

The missing number, and why it matters more here

On a mains blanket, a missing wattage is an inconvenience: you cannot work out the running cost, but the blanket works. On a 12 V blanket it is a functional gap. The question every buyer has is how long it will run off their battery before the battery is flat, and that question is arithmetic: watt-hours of battery divided by watts of blanket gives hours.

We checked all four 12 V products we track. None publishes a wattage. None publishes an amp draw. Camco's listing goes as far as claiming a low amperage draw to avoid draining your battery, which is precisely the claim that needs a number attached, and does not have one.

Camping: hookup or no hookup

The single question that decides which product you want.

• Campsite with mains hookup. Use an ordinary mains blanket. It is bigger, warmer, cheaper, and better documented. A 100 W blanket for eight hours is 0.8 kWh, which is nothing against a site's hookup allowance.
• No hookup, vehicle engine running or a decent power station. A 12 V blanket is the answer. Sealy names portable power stations explicitly as a supported use.
• No hookup, no vehicle, no power station. No heated blanket helps you. This is a sleeping-bag-rating problem, and no amount of shopping in this category solves it.

The full version, including how to think about a power station without a published wattage to work from, is on heated blankets for camping.

Cars and RVs

Different constraints from camping. The blanket is for passengers rather than sleepers, sessions are short, and the engine is often running so battery drain is not the issue it is at a campsite. The specs that matter here are cord length, because the point is usually to reach the back seat, and auto-shutoff, because a blanket left on in a parked car is exactly the scenario the timer exists for.

Sealy and Westinghouse both publish an 85-inch cord. Camco publishes 7 feet, which is 84 inches, and adds a 1-year warranty that neither of the others matches. Sealy publishes a 4-hour auto-off; the others do not state a duration. Full detail on 12V for cars and RVs.

Choosing for a specific person

Three groups come up often enough in search to deserve their own pages, and in each case the right pick is decided by a specification rather than by warmth: an older user needs a controller they can read and operate, which is a display-and-button question; someone with joint pain wants a published temperature range so they know what they are getting; and a memory-foam mattress changes where the heat can usefully go.

Those are heated blankets for older adults, for arthritis and joint pain, and on a memory foam mattress. The arthritis page in particular carries the same non-medical-advice line as everything in safety: we can tell you what the makers publish, and that is all.