CASE STUDY: ECM vs. PSC Motors
Energy Efficiency: ECM vs. PSC Motors
Motors are one of the most important components in a vertical fan coil unit. It drives the fan, which provides all of the ventilation in a residential suite. Due to the regular use of the fan, it contributes a lot to vertical fan coil energy consumption. Updating motors can drastically improve fan coil energy efficiency, so it’s important to know what’s available to you.
Permanent Split Capacitor (PCS) Fan Coil Motors
Permanent split capacitor (PSC) motors have been used in vertical fan coil units since the 1970s and 1980s. They are a low-cost option that operate on alternating current.
PSC motors can not be programmed to adjust the rate of rotation. The speed does not vary, so the motor effectively turns on and off. Since the speed is constant, the energy use is as well. This means the motor consumes as much energy as it can every second it is on. Sometimes PSC motors fail to provide good ventilation when the static pressure becomes to high because they can not increase their speed and torque to account for an increase in pressure.
These motors also require an external capacitor to help them start & run because of their low power factor. The external capacitor can often fail which results in the motor not functioning as intended. The low power factor also means that PSC motors require more expensive wiring to accommodate the energy needed to run the motor.
Electronically Commutated Modulation (ECM) Motors
Electronically commutated modulation (ECM) motors are relatively new to the HVAC world in condos and apartments. While some developers started using them earlier, most have now adopted ECM motors in their fan coils. They have a higher initial cost and run on direct current.
They are an incredibly flexible motor. ECM motors can be programmed to control the rate of rotation or speed. Allowing for variable speeds means they can ramp up to deliver excellent ventilation when there is increased static pressure. It also results in less energy consumption when there isn’t a need to run at such a high speed. ECM motors also sound quieter and this is partially due to the fact that the speed builds up. It doesn’t go full blast right away.
ECM motors also run a lot cooler than PSC motors. This causes less wear and tear on the motor which means it has a much longer life expectancy.
Unilux RFC Uses ECM Fan Coil Motors
All Unilux RFC retrofit systems are equipped with ECM motors. This allows us to program motors to improve your comfort at home. We can reduce the motor noise, optimize the motor for your suite and reduce the energy the motor consumes.
One of the largest benefits of replacing your fan coil unit is the energy savings. You’ll see real energy savings thanks to ECM motors – the workhorse of your Unilux RFC.