Heating pad no longer getting hot after a week?

Factual Questions
1

I’ve been getting bad hand and forearm cramps at night. Probably because I’m lifting barbells again in the evening.

I bought a small 12x15" heating pad. Rolled it loosely into a tube and secured with two large rubber bands.

Slide my arm in for 15 mins and heating the muscle relaxes it and prevents the cramps. I do both arms.

It worked great the first 4 nights on medium. High gets too hot. There’s a little sweat on my forearm afterwards.

Now it’s barely getting warm on High? My arm didn’t even sweat last night.

I know if the heating element burned-out the pad wouldn’t work.

Is it unusual the pad still heats at about 50%?

I’m returning it to Walmart for replacement. I’m concerned the replacement will do the same thing after a few nights.

They only cost $16. But I can’t replace it every week.

2

Because you’ve rolled it up, perhaps there’s a sensor that cuts power to prevent damage to you or the pad?

3

I planned on changing strategy with the replacement pad. Reducing the time to 10 minutes and turning it off.

Wait 30 mins and then do the other arm.

Maybe I ran it too long and damaged something? It is just a cheap $16 heating pad.

I could try laying it flat on my arm. It might warm it some. But the underside of my arm wouldn’t get any heat.

4

A piece of shiny Mylar, as in a space blanket, under your arm might reflect enough IR to supply some heat underneath. But probably not as much as you’d like.

Or get one of these

5

That arm wrap is what I need.

Instead of trying to improvise with a flat pad.

I can feel the tightness in my hand and forearm a few minutes before the cramps begin.

Heat seems to relax the muscle before the cramps begin.

Ordering now.

6

Hard to know without actually examining it, but it is possible that the pad has two or more heater elements in it, and it implements lower setting by only turning fewer of them on, rather than adjusting the current in one single element? So if one element has failed, the other(s) may still work to provide lower settings.

I would experiment with a multimeter to try to see how the resistance reads on different settings. Though if it has a semiconductor control circuit, which is quite likely these days, that might not give a very clear answer.

Hopefully a replacement is unlikely to suffer early failure, unless the manufacturing process is VERY shoddy, or they just got a bad batch in…?

7

Glad to have been of service. :smiley:

8

Those cheapies don’t stand much abuse. I had one and left it on. When I came back my cats were on it. For maybe 10 minutes. It never heated right after that. I’m sure to put my new one off and away when I leave the room now.

9

Cats can suck the heat out of it.:cat:

10

I put my pad on the floor under my desk to keep my feet warm. The cats use it more than I do. The pads usually last at least a year. I don’t remember how much my current pad cost, but I don’t think it was that expensive. But probably not a real cheapie, either.

11

Have you received your heated arm wrap yet? We need a usage report.

12

It’s coming in this week. I’ll be cautious and keep it on low heat. I expect it will get hotter than the cheaper sunbeam pad.

13

Excellent, be sure to report

14

I bought this heating pad. It’s long enough to wrap a ankle, knee, arm or shoulder. The instructions offer advice on wrapping.

Several pads were USB. I was concerned they wouldn’t handle the current requirements. The pad I bought has a 12v transformer for power.

Works well so far. I use it on the lowest heat setting for 20 mins. It has a 2 hour auto shut off. I certainly wouldn’t want it on my arm that long! I assume the shut off is for fire safety in case someone didn’t turn it off.

We had a winter storm Sun night. It’s 5F now and this pad feels very good in my drafty house.

Link Hand Arm Heating Pad for Pain Relief, Large Heat Areas for Joints Pain Soreness,Heated Wrap for Wrist Ankle Elbow Knee and Leg,2 Hrs Auto-Off 3 Heat Settings,78.7 Extension Cord Black https://a.co/d/0jbqaEp

15

Great to hear you’ve found something that will work for you. Thanks for the report.