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SKE4 - Resistive electric steam humidifier

Overview header Specisfications header 1
Steam Distribution
  • In-duct or in-space distribution systems
  • Multi-Steam SD/HD and S.A.M. systems available
  • SDU (Space Distribution Unit) for in-room distribution
Outdoor Unit
  • Fully insulated
  • Easy installation
  • Anti-freeze and overheat protection
Designed specifically for the SK4 series
  • One controller
  • One menu across humidifier types
  • Provides consistency and ease of use
Sensors and Controls
  • Higher energy conservation
  • Lower costs and higher values
  • Seamless integration and interoperability
  • Overview

  • Steam Distribution

  • Outdoor Unit

  • Integrated,
    Multi-Platform Controller

  • Humidity Sensors and Controls

SKE4 - Overview

The resistive heating elements of the SKE4 transform electrical energy into heat that boils the water, producing steam. The process allows mineral-free, odorless and sterile steam to be generated quickly with any type of water.

  • Environmentally friendly
  • No plastic cylinder to replace!
  • Permanent stainless steel evaporation chamber
  • Optimize the use of boiling water – no unnecessary drain!
SKE4 OVerview Models
SKE4 OVerview Brands


  • Capacities from 5-120 kg/hr
  • Separate and isolated plumbing, controls, and high-voltage sections
  • Remove the stainless steel evaporation chamber with ease, no tools required!
  • Patent-pending water level detection system using two independent sensor technologies
  • Drain water tempered to below 140°F (60°C)
  • Patented Anti-Foaming Energy Conservation (AFEC) System
  • Available with BACnet MS/TP or Modbus communication interface
  • Optional ethernet module for BACnet IP or Modbus IP, and Web services
  • Integrated scheduling system for unit operation, set points, and drain cycling
  • Now available with an OSHPD option – the SKE4 meets the requirements of OSHPD Special Seismic Certification Preapproval (OSP)

System Overview

SKE4 parts chart

In-Duct Distribution

For Multi-SteamTM SD/HD and S.A.M. in-duct distribution systems.

  • Efficient and economical, S.A.M. and S.A.M. E2 systems are suitable for installations where absorption distances are short (less than 5ft/1500mm) and/or low/restricted duct temperatures are present
  • Custom-made to the dimensions of the duct or AHU, the Multi‑Steam™ SD/HD systems are used at critical locations within the air handling systems where absorption distances are extremely short (less than 3ft/900mm) or where low air duct temperatures are present
  • For more information on our Steam Distribution Systems, please click here

Multi Steam





SDU (Space Distribution Unit)

  • Quiet operation
  • No condensation
  • Local or remote in-room steam distribution
  • 3 models available (SDU4-1, SDU4-2, and SDU4-3)
Space Distribution Unit

Operation in all Climates

  • Outdoor Unit capacities from 2.7-122 kg/hr
  • Fully insulated and constructed from heavy-duty steel
  • Stainless steel bottom drip pan
  • Zinc primer and polyurethane powder coating for resistance against scratches and corrosion on the exterior and interior surfaces
  • Built-in anti-freeze and overheat protection
  • Easy installation on a roof curb, stand or slab
  • Connection can be made from side or bottom of unit for flexibility in any configuration
Outdoor Unit

The SK Controller is configured specifically for your SKE4, SKG4 or SKS4 Humidifier.

  • User-friendly, menu-driven interface on a 128 x 64 LCD with 8 function buttons for faster configuration and operation
  • User rights management allows for menu to display only functions available to the category of user logged in
  • Quick Config menu allows for faster and easier installation, by displaying only the most commonly used functions and configurations
  • Integrated scheduling system for unit operation, set points, and drain cycling
  • In-field firmware upgradeable via SD card, USB or BACnet
  • Simple viewing and exporting of trending log and alarm log

Optional Features

  • The selectable BACnet MS/TP or Modbus communication interface allows access to over 75 objects/registers for integration with a BMS and IoT(Internet of Things)
  • Ethernet Module
    • Bacnet IP or Modbus IP
    • Web services make it possible to perform humidifier configurations, remote diagnostics and many more functions from any location
controller 2

An updated and highly accurate line of sensors and controls was developed and produced by Neptronic specifically for the new SK4 series.


  • Used to program the SK humidifiers
  • Icon-driven information and 1 line of text information
  • 4 wires between humidistat and SK
  • Programmable PID on humidity


  • BACnet MS/TP (model HROB20 only)
  • 4 analog and 2 dry contact outputs
  • 2 external sensor inputs
  • Alarm and low signal selector input
  • Independently configure PID on humidify & dehumidify ramps
  • Adjustable setpoint with auto reset from external sensor


  • SHS20 - High-limit setpoint dial (20 - 90% RH)
  • Built-in humidity sensor
  • 24Vac or 24Vdc
  • 1 dry contact output


  • HRC20 - Humidity setpoint dial (10 - 60% RH)
  • Built-in humidity sensor
  • 24Vac or 24Vdc
  • 1 dry contact output


  • Built-in temperature sensor
  • Plastic cover for wall mount installation
  • 2 analog outputs (0 - 10 Vdc)
  • High accuracy and stability


  • Built-in temperature and humidity sensor
  • 2 analog outputs (0-10 Vdc)
  • Status LED


  • Built-in temperature and humidity sensor
  • On/Off high limit humidistat with on-board setpoint adjustment
  • 2 analog outputs (0-10 Vdc)
  • Status and high limit LEDs
  • 1 dry contact output