OEM vs. Aftermarket Appliance Parts in Rental Units

For rental units, use OEM vs. aftermarket appliance parts by risk. A good aftermarket part is fine for gaskets, knobs, shelves, racks, drain pumps and many heating elements and igniters. Anything that controls gas, guards against fire or overheating, or runs the appliance's logic (gas valves, safety thermostats, door locks, control boards) should be OEM. The deciding question is what happens in the apartment if the part fails.

What the two terms mean

OEM (original equipment manufacturer) parts are made by, or for, the appliance's manufacturer and carry its part number. They're what the appliance shipped with, or the manufacturer's updated replacement.

Aftermarket parts are made by someone else to fit the same appliance. Some come from the same factories that supply the brand. Others are copies built to a price. Sellers sometimes call them "OEM-equivalent" or "fits [brand]", and the packaging rarely tells you which kind you're holding. Quality varies a lot. Two gaskets with the same listing photo can fit very differently.

There's a third category worth naming: used or salvaged parts pulled from scrapped appliances. They are genuine, but with unknown hours on them and usually no return. For a rental we treat them as a last resort for an NLA (no longer available) part, never a default.

Why aftermarket is tempting

Price is the obvious reason. An aftermarket gasket or drain pump often costs noticeably less than the branded one.

Availability is the less obvious one. When the OEM part is backordered, an aftermarket version may be on a shelf today. For a refrigerator in an occupied unit, that difference is days of tenant downtime. (Our note on why parts get backordered explains how those delays work.)

Neither reason matters if the part fails early or does something unsafe. A part you buy twice costs more than one you buy once. A cheap part that brings the technician back in two months costs a second service call, another access window and another tenant complaint.

OEM vs. aftermarket appliance parts, part by part

The split follows the consequence of failure. If the part fails and the worst outcome is that the appliance stops working, a reputable aftermarket part is a reasonable choice. If the worst outcome is gas, fire, flooding or an electrical fault, buy OEM.

A note on igniters, because they're the part people get wrong most often. On many gas ovens, the igniter isn't just a spark source. It warms up and draws current through the gas safety valve, and the valve only opens once that current is high enough. A weak igniter, new or old, can glow orange and still not open the valve, or open it late. That's why "it glows but won't light" is a common complaint, and why a bargain igniter that's slightly out of spec just recreates the fault.

Water parts deserve more weight in multifamily buildings than in houses. Here's why. A failed inlet valve in a single-family home is one wet kitchen. In a walk-up it's the ceiling of the unit below, a second tenant, and sometimes an insurance claim.

What it means for the appliance warranty

Using aftermarket parts doesn't automatically void a manufacturer's warranty in the US. The FTC's Businessperson's Guide to Federal Warranty Law explains that, under the Magnuson-Moss Warranty Act, a warrantor generally can't make coverage conditional on using its own brand of parts or service, unless it provides them free or has an FTC waiver. The same guide says a warrantor can refuse to cover damage caused by parts or service it didn't provide.

In practice, that second sentence is the one that matters. If an aftermarket valve leaks and ruins a control board, the manufacturer can decline the board. And while the appliance is still under its original warranty, most covered repairs go through the manufacturer's authorized servicer anyway, who will use OEM parts. (This is general information, not legal advice.)

Our note on using appliance warranties in rental buildings covers registration, records and authorized-servicer rules in more detail.

How to find out which one your vendor used

Ask before the work, and check the invoice after. Neither is awkward. It's a normal question. A good vendor will tell you without being pushed.

1. Ask what the vendor's default is. Some use OEM for everything; some use aftermarket unless you ask otherwise. Either can be fine if they say which.
2. Ask for the part number on every invoice. An OEM part number can be looked up against the model. "Replaced valve" with no number tells you nothing.
3. Ask them to mark OEM or aftermarket on the quote. You can approve the aftermarket gasket and require OEM on the gas valve in the same job.
4. Ask for a photo of the new part in its packaging, or of the old part next to the new one. It costs the technician seconds.
5. Ask what happens if the part fails. That answer tells you how confident they are in the part and who pays for the second trip.

Vague invoices and parts with no numbers are worth paying attention to on their own. Our note on red flags in an appliance repair vendor covers what else to look for in your records.

A quick example

Say a dishwasher in 3F won't drain, and the technician finds a failed drain pump. The OEM pump is backordered for two weeks; a well-known aftermarket pump for that model is in stock locally. That's an easy call: approve the aftermarket pump, note it on the unit record, and the tenant has a working dishwasher this week.

Now say the same visit turns up a weeping water inlet valve. Different answer. Wait for the OEM valve, or at least have the water supply to the dishwasher shut off until it arrives. A slow drip on the kitchen floor is a nuisance. Behind a cabinet, unnoticed for a month, it's a ceiling repair downstairs.

A simple policy you can give vendors

If you manage more than a few buildings, write the rule down once instead of deciding each job. Something like this works:

"OEM required for gas components, control boards, door locks and switches, water valves and any safety or overheat device. Aftermarket acceptable for gaskets, knobs, shelves, racks, drain pumps and heating elements of matching rating. All invoices to list part numbers and mark OEM or aftermarket."

Put it in the vendor onboarding packet and on your work orders. It saves the back-and-forth on every quote, and it means the cheaper part goes in only where a failure is an inconvenience rather than a hazard.

Settle the part choice at the quote

The part choice comes up at the quote, so that's where to settle it. Tell your vendor your policy up front, and ask them to flag any job where the OEM part is backordered and an aftermarket one is in stock, so you can make the call with the tenant's wait in mind.

When you open a work order with us, every repair is quoted for your approval before work starts. If you want OEM-only on certain parts, say so in the request so the quote reflects it.