M-D Building Products 64386 9-Foot Pipe Heating Cable with Thermostat

I used this per the instructions on a short piece of "rigid plastic pipe" for my outside well pump house. When my water stopped pumping I discovered this heating tape had burnt to a crisp the plastic pipe and nearly burnt my pump house down. I'm grateful I caught it in time. Instead of a very expensive and dangerous situation, I only have to replace the pipe and a $125 filter. I'll be contacting the company directly. NOT RECOMMENDED ON PLASTIC PIPES.

I used this product for two seasons, the first being Nov. 2015. It failed during the cold spell we had Jan. 2018. It worked well until then. I would say it's okay, but to be safe if you have a really cold spell and you're living in a RV best open your grey water valve a bit and let your water trickle some to be safe. The lines in our RV are fine. The hose froze even though it was insulated along with this product. Frankly, I don't know of a better option, just not sure this is the best product for my application. Abviously, it's only used during the winter months when temps are expected to be freezing. So, durability seems to be an issue.

The thermostat (knob located at the end of the cable) MUST be attached to the piping that is exposed to the cold; otherwise, thermostat won't heat up. Thermostat senses cold, then heats up. Cable heated up immediately when I attached the thermostat end to the cold pipe; HOWEVER, it is less than 0 degrees outside and the outside wall the plumbing is located on in the crawl space is so cold, the water pipes are still frozen despite being warmed somewhat by the heating cable. The crawl space walls are lined with fiberglass insulation. I attached the heating cable to the water pipes with zip ties.

So far so good. I have only had this installed for a few weeks, but wanted to post since I think they may be either shipping cables that are slightly different or maybe they have switched to a newer model. In reading the reviews some reviews report that the lighted plug is on all the time and some report that the light comes on when the cable is actually heating. On the cable I received this year (2016) the light is ALWAYS on and seems only to indicate that the circuit is complete and the cable has power. In order to test my cable I held a bag of ice against the thermostat and was able to hear it kick on and get warm. I'd recommend doing this test before you install it to make sure you didn't receive a dud cable. It's much easier to test before installing rather than finding out you have a problem later and having to rip it out and return it. I plan to test it at least annually by icing the thermostat.UPDATE - it has been a year since I purchased and installed this cable. Before winter set in I climbed back in my crawlspace and removed the zipties that I used to mount the thermostat so I could test it with a bag of ice. Sure enough, once it got cool enough I heard a slight audible click and the cable warmed up. I reinstalled the thermostat with zipties and climbed back out. I'll do it again every year but so far so good.UPDATE - just did my annual test (11/2020) and my cable is still working flawlessly. That being said, my cable is exactly like the one pictured here (orange on plug side, heat shrink tubing on a T shaped thermostat, black cable on the heating side). I have read reviews and seen online that they are now selling a purple flat cable type of heat cable and I have no experience with that one.

The Amazon photo for this product shows the cable spiraled around the pipe. The product description touts "easy wrap-around installation." The description also says the product has a light that shows if the thermostat is working. To make sure the product could be spiraled, or a least installed on a pipe that has a bend in it, I set up a chat session with the vendor. She contacted another party and gave me the message that the product could indeed be spiraled and/or placed on a 90 degree bend in a pipe, just as long as the cable did not cross over itself. NONE of this turned to match with the instructions in the product that was sent. The instructions specifically state that spiraling the product will create fire hazard. There is no light to indicate if the thermostat is working. Instead there are instructions to place a bag of ice on the thermostat, plug the cable in and see if the cable gets warm. There is a built-in power indicator light in the plug that does nothing to show if the thermostat itself is working and is redundant to my power cord that shows there is a properly grounded power source providing power. Do not buy this product. It cannot be used as advertised

I'm not sure how to review heating cables. I installed it as directed and we've had the lowest temperatures in almost 20 years. I've had no freezing problems on an outside, exposed water line. I guess the cable did it's job. I covered the wrapped cable with foam insulation tubing and then used wire ties to secure the insulation. I also covered the shutoff valve with a foam enclosure that is sold in hardware stores and places like Lowes for a couple of dollars.A couple of years ago, during a playoff football game, I heard water running and ended up doing the repair with a trouble light in sub freezing temperatures. It was then that I decided to apply a heating cable. The one available from my local hardware store lasted for a few years and then failed. This one is much better quality.

First cold snap after the install... the thermostat didn’t trip, the heat trace never came on, and the pipes and pump froze solid. No water for me until I rigged up a space heater to warm the pump house up.BUT!!!That cute little light inside the plug worked! One star for that cute little light inside the plug.