KB2407-ECO Heater is Heating Things Up

King Electrical Is Heating Things Up – KB2407-ECO Heater

In August of last year, the TBB crew worked on converting my old screened in porch to a new workshop space. The crew finished the exterior framing, sheathing, windows, and clapboards in two weekends. Rob, Mike D. and I worked to insulate and drywall the interiors during the months of September and October.

Approaching the winter, we discussed several ideas about how to heat the new space. We considered wood stoves, pellet heaters and even a small propane furnace under the structure. The final solution that made the most sense was to find a high-capacity electric space heater.

King Electrical Manufacturing – KB2407-ECO Heater

My new workshop is about 310 sq. ft. with a 10’ high ceiling. For this sized workshop, I determined that a 7 KW heater would work well. I wanted a fast recovery time for when I heat the space from a cold start to working temperatures in the mornings. The King Electrical KB2407-ECO heater from King-Electric fit my requirements to a tee.

Important Features

The KB2407-ECO is a 25,600 BTU / 7KW heater. It has a number of important features:

  • Smart ECO2S Energy-Saving Design
  • 2-Stage Heating: Automatically Uses Lowest Wattage Needed
  • Remote Control Included & Wall Holder
  • Summer Fan Only & Timer Modes
  • Built-In Fan Delay To Dissipate Heat
  • High Mass Steel Fin Heat Exchanger
  • Patented Smart Limit Protection®
  • Permanent Lubricated Unit Bearing Motor
  • Universal Wall/Ceiling Bracket Included
  • Proudly Made in the USA
  • 5-Year Warranty
  • Review Additional Product Information at www.King-Electric.com

Heater Performance, Observations and Tests

The King ECO2S KB series unit heaters, as a group, offer unparalleled performance, energy efficiency and user control. I was particularly impressed with the innovative built-in electronic thermostat and the companion remote control. I mounted my remote control right next to the entrance door of the shop.

Two Cycle Heating

My KB2407-ECO offers energy efficient 2-stage heating, with an Eco mode that automatically uses the lowest wattage needed to heat the room. I conducted a test and I found that when I tasked the heater to heat my workshop by 20 degrees, the heater pulled a consistent 28.7 amps until the thermostat was within two degrees of the target temperature. Then the heater cycles in a two stage mode between 28.7 and 16.2 amps to reach the desired temperature and keep it at that setting. I copied my 20 degree test results in the following graph where the reader can see these amperage readings.

In addition to the two stage cycle, I noticed the heater has an integrated fan-only and timer modes that will be a nice feature in off-season usage.

Heating Element

The KB2407-ECO has spiral steel heating elements and a high CFM 5 blade fan that ensures even air distribution. King designed the unit to produce cooler heating element operation to prolong the life of the heater. The metal-sheathed heating element is copper brazed with spiral fins then molded into a coil configuration. This combination produces the heat transfer while eliminating the potential for hot spots by positioning the element in the maximum airflow stream.

For heaters, like mine, over 5kW in capacity, King Electrical designed the dual the line voltage control to operate a set of contactors to switch its dual cycle heating loads. Anyone in the space will notice the clicking of these contactors. After the first day in the shop, I found that I got used to the frequency and timing of the contactors and I now ignore it as white background noise.

My KB2407 has a dynamically balanced fan blade, and it is extremely quiet for this type of fan. I measured the average sound level at 59.8 db at a distance of 4 feet. I expect with its high quality design and features, the KB2407 heater will provide years of trouble-free service and keep my heating bills to a minimum.

KB2407 Installation Was a Breeze

I used the King Electrical website to size the heater and to size the electrical service for it. For my 7.7 KW heater, the Pro Tip section of their website showed the following electrical circuit information:

I checked this with my Master Electrician and he verified that because the National Electrical Code views heater loads as continuous, the circuit must be down-rated by 20%. As you can see, King Electrical has incorporated the NEC requirement in its electrical table. That is why the table shows my 40-amp breaker for a 32 amp continuous load.

Wiring to the Heater

I wired my heater with #8/2 BX cable, backed up with a 40 amp 2-pole breaker. The circuit panel is about 30 feet away from the heater location.

I took a time-lapse video of the installation so that I could see how long the installation process took.

The longest part of the installation process was to install the BX cable from the panel breaker to the heater location. This took 28 minutes.

Hanging the Heater

Once the electric cable was through the wall in the workshop, It took less than five minutes to attach the wall/ceiling bracket and hang the heater on the wall. Initially, I hung the heater at a low elevation because I wanted to have it heating the space while I finished up the high portion of the wall. Then, I planned to move the heater to its final height. The picture, below, shows the final location of the heater on the newly finished upper wall.

The KD2407-ECO heater has an access door for the final wiring connections. I opened the access door with a single screw.  The access door remains on the heater in an open position because it has a continuous hinge at the front of the heater.

The final electrical connections took only a few minutes to complete.

Not including the wiring run, I completed the heater installation and connections in under ten minutes. The folks at King Electric make a product that well thought out and is easy to install.

After I completed the upper portion of the wall, I relocated the heater to its final location – right below the ceiling. Then I removed the heater and temporarily supported it while I relocated the bracket. After that I simply re-hung the heater. Since it only weighs 28 lbs. ,I had no trouble repositioning and attaching the heater onto its bracket.

How’d It Heat Up?

From experience, I know that the ECO heater can heat my shop at a rate of 1 degree F per minute. To get this data, I had to figure out a way to log amperage readings for approximately 15-minutes, so I used the Fluke a3001 FC Wireless iFlex AC Current Clamp Kit. Read about how accurate this heater is.

Final Thoughts

In conclusion, I am extremely pleased with the KB2407-ECO heater. I had an easy time installing it because the King Electric Manufacturing product is well designed and developed with installation in mind.

The only suggestion I would make is to have the contactors sound insulated as some visitors to the shop notice the clicking noise.

I highly recommend purchasing a KB2704-ECO heater, or any of the King Electric products that match your needs.




About the author

Stan Durlacher

Stan has been involved with Design and Construction in the commercial industry since 1975. He is currently the President of Design and Construction for a major St Petersburg, FL developer. Before that, he was a Project Executive for a prominent Boston Construction Manager, building high-rise apartment and office buildings. One of the hallmarks of his career has been innovative problem-solving. As Assistant Secretary of Transportation for the Commonwealth of Massachusetts, Stan was instrumental in bringing the hydro mill slurry wall machinery and technology to Boston in the 1990s for use on the Central Artery Third Harbor Tunnel Project. Stan has been an avid woodworker since college and brings an innovative point of view to this field. Before Florida, he owned an 1886 farmhouse near Concord, Mass, and his skills and time were never idle for long. His barn and attached spaces serve as his ever-expanding workshop. Stan is a self-avowed tool hound. In 2013, Stan decided to design and build his own CNC router. This machine has become a centerpiece of his woodworking and craft focus. Stan will share many of the ways that this innovative technology has solved many current problems and how CNC will begin to impact the woodworking and home renovation businesses.

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  1. […] recently installed a King Electrical ECO KB2407-ECO electric space heater in my workshop. It is a great piece of equipment. ECO rates my heater for 30 amps and I wanted to […]

  2. kyle hollingsworth

    How would you have the contactors sound insulated? Thanku!

    1. Stan Durlacher

      Hi Kyle. Thanks for the question. After running the ECO Heater for a while, I got used to the contactors opening and closing.
      I personally would not try to retrofit the inside of the heater with sound insulation for safety reasons.
      A more appropriate mitigation might be to put acoustical panels or attenuation materials around (Not too close to) the heater to deaden the sound.
      As this type heater is used in shop/industrial settings, I would advise anyone wanting to purchase the ECO Heater to be aware that there will be noticeable contactor noise.
      Thanks again for the question.

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