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Portable Heating Thermostat With Piggyback Plug

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Portable Heating Thermostat With Piggyback Plug

Eventherm , TH-4-20 8PL

QC Supply Part #: 10920

Shipping: Standard

Availability: In Stock

A dependable and affordable way to maintain consistent temperatures.

Includes 8' Replaceable Cord.

This corrosion-resistant Portable Heating Thermostat can be used in all buildings. Simply plug the thermostat into an outlet and plug the heating equipment into the piggyback plug.


  • Watertight, Nema 4X rated
  • Stainless steel sensing coil
  • Calibration dial is adjustable
  • Designed to tolerate harsh environments, high humidity levels, corrosive elements
  • Used for heating
  • 1-year warranty
  • Differential: 2.5° F
  • UL listed
  • 40° F to 104° F
  • 20 Amp @ 110V; 16 Amp @ 240V
Manufacturer Part Number TH-4-20 8PL

Customer Reviews

Works great
Review by Tim on Nov 20, 2015

Workss great

Excellent product
Review by Mandowneast on Oct 24, 2015

Fast arrival and works as described

Works Well!
Review by Grizzly on Jan 17, 2015

Works well with electric heater that has bad thermostat!

The very best efficiency!
Review by Guy on Dec 27, 2014

The thermostat appears to be very accurate and performs with consistency. The area being heated is being maintained at a comfortable 72 degrees. I feel that by using this thermostat, I am saving money and energy over the control provided by the thermostat of the heater unit itself. The heater runs less often, but the temperature is maintained. I would recommend this unit to anyone seeking a means of maintaining a uniform temperature in a given space.

Great product & company.
Review by PT on Nov 21, 2013

The unit is packaged well & works as advertized. It is priced right & installs easily. Would highly recommend this product & company.

Dead-on accurate, super quality
Review by George on Nov 10, 2013

This is actually a waterproof unit but obviously with the power cord, the same isn't true. It's MUCH higher quality than the old-time remote bulb mechanical types--even the sensor is stainless steel. It's a fair amount of money but well worth it and, of course, QC is the quality place to buy it.

So Far So Good
Review by Home User on Nov 6, 2013

So far it does what I want it to do, at that is keep my greenhouse from going below 45 degrees.

Review by snake on Mar 24, 2013

not that accurate

Review by Bruce on Mar 9, 2013

Great product. I used one of these on each heattape circuit (20 AMP) on the incoming water lines and outgoing sewer line in my Condominium Association. Previously, the heattape circuits were turned on from November through April. Now they only come on when necessary. A big savings in electricity.

Review by coach seb on Feb 13, 2013

Works well and easy to install

Excellent product. Top rate dealer
Review by Dick on Jan 12, 2013

I am using this product presently in the cellar of a storage building where i store potatoes thru the winter. I am very pleased with this thermostat control as it keeps room at an even temperature. I also plan to use it in my greenhouse. I very much appreciated the rapid shipping by QC.

Review by Russ on Dec 26, 2012

Bought the thermostat to keep my boat engine from freezing up in the winter. So far so good. The unit seems to be very well made and I would highly recommend it to anyone looking for a quality device that will be used outdoors or in harsh environments.

Good Product
Review by Mike on Dec 1, 2012

I have a bathroom space heater with a bad thermostat. The manufacturer could not give me a replacement part. This product has allowed me to keep using my space heater with even better control than before! The manufacturer sent me a replacement heater since it was still under warranty, but I did not want to send the old heater to the landfill if I could still use it. The new heater is still in the box!

Great Unit!
Review by Alec on Apr 7, 2012

Nice quality unit. Accurate & east to install. Also it is the best priced in-line thermostat I could find.

sturdy and accurate
Review by ND farmer on Dec 18, 2011

Bought it to control an electric fireplace in the house so the elements aren't a concern for me but it is accurate, it holds the room at a constant as I set it. Simple to use, just plug it in. Long enough cord to get away from direct heat of the heater too.

This thermostat appears well made
Review by Jerry on Feb 18, 2010

I am using this product a area that is subject to high humidity to control a heater protecting a room from freezing.

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