Click here to view a capacitor start motor circuit diagram for starting a single phase motor.
Do ecm motors have capacitors.
Although electronically commutated motors ecms are specified in efficient buildings and energy efficiency programs provide incentives for their installation i only had a cursory understanding of the difference between this technology and traditional shaded pole or permanent split capacitor type motors.
What makes ecms more efficient.
To learn more read our article all about ecm motors.
The first thing to know is that an ecm motor is brushless dc motor.
I believe you have an x13 blower motor in your air handler.
On that type of motor it is usually the module on the end of the motor that goes bad.
These motors are quickly outpacing other common motors as they are now dropping in price and can be used in hundreds of different applications.
When the blower runs is it loud.
In marginal systems with higher than design static pressures for example a 5 in.
However not all ecm motors run at variable speeds and selection depends heavily upon application specifications.
During a motor s start up a switch connects a capacitor and a special starting coil to the.
Welcome to the forums.
An ecm motor is some times referred to an a variable speed motor.
Permanent split capacitor or psc motors are small inexpensive and popularized ac motors.
Most traditional dc motors require brushes to provide power to the motor rotor spinning part.
Tesp rated furnace with ecm on a 8 in.
Tesp system the motor still may be able to maintain airflow close to design.
Ecm motors do not utilize capacitors external to the motor.
So if the ecm is for the indoor unit the blower motor then you most likely have undersized duct work for the size of unit.
Also read about the speed torque characteristics of these motors along with its different types.
Ecms in hvac systems.
By zureks own work cc by sa 3 0 https commons.
Usually but not always it is a thermistor inside the module that fails.
A capacitor connected to a separate coil on the motor creates an alternating electric current ahead of the main phase by 90 degrees.
I would have hoped that the installation was done correctly based on duct work capability.
The initial cost of an ecm can be high but is typically balanced by overall energy savings in the long run.
In residential and light commercial hvac we have seen ecm variable speed x13 motors for years primarily in blower motors but sometimes even in condenser fan motors.
But in the truest sense all it trying to do is maintain a programmed cfm.
When considering an ecm for application in an hvac system there are several factors to keep in mind.
When a furnace or air handler with an ecm is installed on a good duct coil and filtration system with static pressures within proper design parameters it can perform flawlessly.
Starting capacitor and switch.
Here are two links to threads that discuss the issue.
Learn how a capacitor start induction run motor is capable of producing twice as much torque of a split phase motor.
It is actually a relatively easy repair.
