JavaScript seems to be disabled in your browser. You should have JavaScript enabled in your browser to utilize the functionality of the website

Skip to Navigation Skip to Content

What You Can Expect:

The most in-stock parts on the planet — all OEM, all the time
Cool technology to make finding and buying parts a breeze, including Serial Number Lookup, PartSPIN® and Smart Manuals, found on partstown.com and our industry-leading mobile app
An exceptional customer experience from the team you know and trust with every email, live chat, text and phone call, provided by a friendly and knowledgeable team
Later hours than anyone else — offering support and shipping all in-stock orders until 9PM ET

Real OEM HVAC Parts Are In This Spring! SHOP NOW

find parts
find manuals

Find Foodservice Equipment Parts

Lennox Y9878 MF 3MDC4 3 TO 4 RHEEM REDUCER

How to get it fast to 43215?

Ship It!

Out of Stock, backorders usually ship in 23-25 days.

Promotional Price:

52.14 $ My Price: $ 52.14

Add to cart

more Purchase Options for Shipping
1-Hour Pickup!

Quantity Available:

Pickup hours: Mon - Fri
My Price:

Add to cart

more pickup options

See Local Inventory
Same Day Delivery!
Our same-day delivery window is now closed. Orders placed at this time will be delivered on the next business day. The Delivery Fee is not refundable if the order is canceled after the driver is in route to pick up the order.

Quantity Available:
My Price:

Add to cart

Card Label

Billing Address

First Name

Last Name

Address Line

Apt or Suite Number

City

Country/Region

State/Province

Zip/Postal Code

Something went wrong. Please try again.

Quantity Available:

0

Quantity Available:

0

Manufacturer:

Lennox

Manufacturer #:

Y9878

Parts Town #:

LENY9878

Units:

Each

Fits Models:

View Models List

Lennox Y9878 Genuine OEM Replacement Part

MF 3MDC4 3 TO 4 RHEEM REDUCER

Required fields.

Card Label

Expiration Date

Billing Address

First Name

Last Name

Address Line

Apt or Suite Number

City

Country/Region

State/Province

Zip/Postal Code

Fits Models
Specs

Length:

1 in / 2.54 cm
Width:

1 in / 2.54 cm
Height:

1 in / 2.54 cm
Weight:

Not Available

HVAC Parts Are Here!

Take Parts Town on the Go!

Find the parts you need to fix equipment!

HVAC Parts Are Here!

Take Parts Town on the Go!

Find the parts you need to fix equipment!

Find Foodservice Equipment Parts

Lennox Y9878 MF 3MDC4 3 TO 4 RHEEM REDUCER

How to get it fast to 43215?

Lennox Y9878 Genuine OEM Replacement Part

New Customers?

Find Foodservice Equipment Parts

Lennox Y9878 MF 3MDC4 3 TO 4 RHEEM REDUCER

How to get it fast to 43215?

Ship It!

Lennox Y9878 Genuine OEM Replacement Part