The ECM Modulator 4Z


The ECM Modulator 4Z package is for Zone systems.

No room for a bypass duct? Don't' worry, The ECM Modulator 4Z has you covered. This control accurately regulates duct pressure in zoned HVAC systems.

It also provides all the same Comfort, Efficiency, and indoor air quality benefits of the standard ECM Modulator 4 packages.

How it works

Like the ECM Modulator 4. The 4Z version modulates a true variable speed blower motor in response to delivered air temperature. However, it also monitors the delivered static pressure, and allows you to set a maximum duct pressure. When zones open and close the 4Z will sense the change in static pressure. If the pressure is below the limit you set, nothing is changed, and the system operates like normal. However, if only one zone is calling, the static pressure may increase to hit the limit. In this case the control will react by slightly reducing the blower speed until the maximum duct pressure in reached. It will then maintain that speed until either the pressure is reduced (by another zone calling) or until the end of the heating or cooling call. What this means for a zone system is that you no longer need to rely on a bypass or dump zone for pressure regulation. This saves you and the homeowner time and money while improving the overall performance and efficiency of the system.

One question we often get about the 4Z is how much the reduced blower speed will affect the duct temperature. The answer is not much. This is due to the fact that static pressure increases exponentially as the air flow increases. Therefore, only a small reduction in air flow is required to produce a large reduction in static pressure. So, while the temperature will be affected, it is not much different than it would be with a bypass. One thing to remember is that in bypass applications the conditioned air is being recirculated through the heating or cooling element. This recirculated air also increases or decreases the delivered air temperature.

Blower speed reduction

Small reductions in fan speed = big savings. The ECM Modulator provides impressive energy savings by intelligently adapting the fan speed to the temperature of the air being delivered to the home. This greatly reduces the average energy consumption during the times that ambient conditions do not require full speed operation. While many manufactures are starting to adopt variable speed systems, FanHandler is the only one that uses the delivered air temperature for speed control. This allows us to safely run the blower at much more efficient speeds.

Blower motor upgrade 
The ECM4 and 4Z packages allow you to upgrade systems with existing PSC or x-13 style motors, to use a high efficiency variable speed ECM. By upgrading these outdated systems with an ECM 4 or 4Z package, your customers can see energy savings of 30% or more. For more information check out our Energy Savings Page.

Other uses

Commercial Applications

The ECM Modulator controls have a 0-10V output that can be used with a frequency drive to control blowers of just about any size in large industrial or commercial applications.

ECM Modulators can be used for more than just air flow.

Circulating pumps, and modulating valves that have a 0-10V or PWM input can also be used with ECM Modulators to regulate flow in response to temperature changes. If you have an application where you want prices temperature control. let us know we can program the heating on cooling ramps to meet your specific needs.

Ventilation applications

The ECM Modulators have been used in a wide variety of ventilation systems to regulate everything from building pressures, to regulating ammonia levels in chicken farms. If you have ventilation system that requires precise control let us know. We are happy to adapt the control to your specific needs.

Fan coil applications

The ECM Modulators can take a 0-10V input from a thermostat to regulate the fan speed in response to the difference between the return air and the thermostats set point. This gives an economical way to upgrade fan coil units to be automatically adjusting.

The ECM Modulators are extremely versatile and have multiple auxiliary inputs and outputs that can be programmed for your application. So, whether you are trying to maintain a specific delta, regulate air flow, water flow, damper position or you have a new idea of your own you want to try out. Please let us know. We are here to help!


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Package Includes

  • The ECM 4Z Control

  • Optional top of the line ECM (1/3, 1/2 3/4 and 1 HP Available)

  • Temerature Sensor

  • Pressure tube and moutning plate

  • 120/240V power cable(with Motor)

  • Comunication cable

  • Instruction Booklet

  • FanHandler 5 Year Warranty and 60 day money back guarantee.

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