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  • Electro Industries Warmflo Select Series 2 - Plenum Heater - EM-WU204D5-SL2

    - 20 kW - 68,000 BTU - 4 Stage - UpFlow 15 inches Wide

    Product ID • EMWU204D5S00

    Available in Stock: 0

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The Electro WarmFlo Select Electric Plenum Heater EM-WU204D5-SL2 is an add-on to an existing Oil, Propane or Natural Gas Furnace or Two Stage Heat Pumps. If you want to connect to 1 or 2 Stage Air Conditoner - then look at our WarmFlo Select SL1 Series Plenum Heaters.

These Plenum heaters modulate the heating elements for precise temperature control.

The Electro Electric Plenum Heater EM-WU204S8-SL1 allows you to use electric heating inconjuction with your furnace or switch to just electricity if the cost of Oil, Propane or Natural Gas get's too high.

The WarmFlo Electric Plenum Heater EM-WU204D5-SL2 enhances overall heating system comfort, performance, and efficiency. Whether you are combining a gas or oil fired furnace or adding an air source heat pump, WarmFlo can maximize your heating system’s performance by monitoring outdoor and warm air plenum temperatures. Complete all-inclusive controls make installation and setup easy. Using our dual energy selector makes switching energy types as easy as a “flip of the switch”.

This WarmFlo Select Electric Plenum Heater EM-WU204D5-SL2 can be used in conjunction with a double stage heat pump. This unit is compatible with single or multi-stage gas or oil furnaces with or without variable speed blowers. This Electric Plenum Heater includes automatic dual fuel control, with manual override switch. A conventional 4-wire thermostat must be used when installing with a heat pump. This unit will not work with a heat pump thermostat.


When used with heat pump and gas/ oil furnace:
Overcomes heat pump “cold air syndrome”
Adjustable minimum warm air temperature
Proportional control - outlet temperature ramps up with decrease in outdoor temperature
Provides a control technology for utilizing the high efficiencies of a heat pump down to at
least 0 Degrees F
Generally provides $400+ annual operating savings compared to dual fuel HP installations

When used with a gas/oil furnace:
Full electric element modulation with target temperature output
Simplified system control wiring
Built-in over-temperature protection
Air conditioning compatible
Optional outdoor sensing
Full kW demand - does not come on unless required by outdoor temperature

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Manuals & Docs

Technical Specs

Electro industries Warmflo Plenum Heater - EM-WU204D5-SL2 Techs and Specs

  • Flow Direction
    UpFlow 15 Inches
  • Modulating
  • Heating Elements
  • Stages
    4 with Element Modulation
  • Volts
  • Amps
    21 - 21 - 21 -21
  • Circuit Breakers
    60 - 60
  • Heating Capacity (BTU)
  • Heating Capacity (Kw)
    20 kw
  • Minimum Air Flow
  • Size - Height
    11 1/8 Inches
  • Size - Width
    16 1/2 Inches
  • Size - Depth
    27 Inches
  • Weight
    32 Pounds
  • Parts Warranty (Years)
  • Heating Element Warranty

Electro industries Warmflo Plenum Heater EM-WU204D5-SL2 Features

  • Smart controller, fully automatic
  • Outdoor and warm air temperature sensing
  • Electric element modulation, increased comfort and uniform heating
  • Electric element modulation, minimum resistant element usage
  • One room thermostat, entire system
  • Controls and reacts with heat pump, tempers output for comfort and total season heating
  • Controls and interacts with any gas/oil furnace, single or staging burner
  • Applicable to single and ECM variable speed furnace blowers
  • Installer setup switch, selects heat pump or non-HP, etc.

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