O.E.M. parts vs. Aftermarket or Universal parts: What’s the difference?

O.E.M. stands for Original Equipment Manufacturer, which basically means if you order a part that is O.E.M., it will be a direct factory replacement part straight from your equipment’s manufacturing factory warehouse. Sometimes O.E.M. is the only option available for replacing a part, depending on how special the part may be. For instance, let’s say you are wanting to replace a condenser fan motor for your outdoor condensing or heat pump unit. In some cases, the motors will be designed with an odd RPM or be an ECM motor, otherwise known as an Electronically Controlled Motor. These are cases where you can’t just go with an aftermarket or universal part. You would have to go with the O.E.M. which will always be much more expensive than an aftermarket part.  But then again, there are a lot of times when using an aftermarket is perfectly fine. It all just depends on the particular unit you have.

So then what’s the real difference? Well, there are certain specifications that need to be matched up depending which part you are looking to replace. As long as there is nothing really special to that part’s inner workings, finding an aftermarket replacement is fairly easy. Part numbers in a situation like this will ultimately be your best friend.

For instance: For these types of parts if a part number is not available, the important points are…

Blower motors or condenser fan motors:  

1.       HP or horsepower

2.       RPM

3.       Voltage

4.       Phase

5.       Positioning and mounting

6.       Rotation

7.       Diameter

Fan Blades:

1.       Number of blades

2.       Hub size

3.       Rotation looking at the hub side

4.       Pitch degree of the blades

Contactors:

1.       Amps

2.       Voltage

3.       Coil voltage

4.       Number of poles

Gas Valves:

1.       These are a bit tricky. The best suggestion here would be to get the part numbers from the valve itself. As an example, let’s say you have a Carrier furnace. Carrier does not actually make the gas valve that’s in there. The part is actually manufactured by a number of different manufacturers. So let’s pretend this one was made by White-Rodgers. There will be 2 part numbers on the valve, the Carrier number which might look like EF32CE233, and the White-Rodgers number which might look like 32C14-285. If you look for the Carrier number, you are looking for the O.E.M. which will always be more expensive. If you search under the White-Rodgers number, at this point you are looking for the aftermarket part. As you see, both numbers reference to the same part, just depending what part number you search for will determine how much the part will cost. Same part, different part numbers. All in all if you go with the O.E.M. you are really just paying for a name.

The rule above can be used in almost every case when looking for a replacement part. And as explained before, there is no difference between O.E.M. and aftermarket parts aside from the cost and paying for a name. All that is needed to find the aftermarket is to search for the actual part manufacturer’s part number to bypass that O.E.M. pricing. Now that you are armed with the proper information to locate the parts needed, you will save yourself a lot of time and money in the future when tending to your HVAC parts needs.