MRCOOL 80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace | MGM80SE045A3A
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MGM80SE045A3A
Reliable Warmth. Efficient Comfort. Trusted MRCOOL Performance.
Keep your home cozy during the coldest months with the MRCOOL 80% AFUE 3 Ton Gas Furnace (Model: MGM80SE045A3A). Designed for upflow or horizontal installation, this single-stage gas furnace offers consistent heating with an energy-efficient 80% AFUE rating—meaning 80 cents of every dollar spent on fuel is converted into heat.
Ideal for homeowners looking for reliable performance and easy maintenance, this furnace features a multi-speed ECM blower motor, a slide-out blower assembly, and rotatable draft inducer for flexible venting.
⚠️ Note: Not available for sale or installation in California due to state energy regulations.
🔧 Key Features:
-
80% AFUE Efficiency
Converts 80% of fuel into heat to maximize comfort and energy savings. -
3 Ton / 45,000 BTU Heating Capacity
Ideal for medium to larger homes or zones needing dependable, even heat distribution. -
Upflow/Horizontal Installation
Versatile configuration with removable floor base for bottom return applications. -
Quiet, Consistent Comfort
High-efficiency 5-speed ECM blower motor ensures even airflow and whisper-quiet operation. -
Durable Internal Components
Includes aluminized steel inshot burners and a non-welded clamshell heat exchanger for long-lasting performance. -
Maintenance-Friendly Design
Easy-access slide-out blower simplifies cleaning and servicing. -
Flexible Connections
Left or right utility hookups plus rotatable draft inducer for adaptable venting. -
Certified for Safety and Efficiency
AHRI and CSA certified, ensuring dependable operation that meets national standards. -
Warranty Protection
Comes with a 10-year parts warranty when registered and installed by a licensed professional.
🧰 Technical Specifications:
-
Model: MGM80SE045A3A
-
AFUE Rating: 80%
-
BTU Input: 44,000 | BTU Output: 35,200
-
CFM: 1230
-
Tonnage: 3 Ton
-
Blower Motor Type: ECM, 5-Speed
-
Electrical: 120V, 60Hz, Single Phase, 15A Max
-
Gas Type: Natural Gas (LP kit available)
-
Ignition: Silicon Nitride Ignitor
-
Heat Exchanger: Tapered, Non-Welded Clamshell – Aluminized Steel
-
Vent Connector: 4"
-
Dimensions: 14.5"W x 28.375"D x 33"H
-
Weight: 111 lbs
-
Restricted States: Not for sale in California
PRODUCT SPECIFICATIONS:
| Product Dimensions | 14 1/2'W x 28 3/8'D x 33'H |
| Product Weight | 111 lbs |
| Unit Type | Gas Furnace |
| AFUE | 80% |
| CFM | 1230 |
| Tonnage | 3 |
| Heating Capacity | 44,000 BTU |
| Fuel Type | Natural Gas |
| BTU Input | 44,000 |
| BTU Output | 35,200 |
| Voltage |
Requires a minimum of 120V/60HZ/15A |
| Phase | 1 |
| Cycle | 60 |
| Stage | Single |
| Max Fuse Breaker | 15 |
| Min Circuit Ampacity | 6.8 |
| Color | Gray |
| Full Load | 6.8 |
| Number of Burners | 4 |
| Gas Connection Size | 0.5 |
| Blower Motor Type | ECM |
| Blower Motor HP | 1/2 |
| Blower Motor Speeds | 5 Speed |
| Blower Motor RPM | 535-1230 |
| Heat Exchanger Type | Aluminized steel |
| Ignition Type | Silicon Nitride Ignitor |
| Vent Connector | 4 inch |
| LP Kit Available | Yes |
| Certifications | CSA AHRI |
| Warranty |
Registered 10 Year Parts Warranty |
| Restricted States | Yes (California) |
Overview
| Manufacturer warranty | 5 Year Parts Warranty |
|---|
Performance
| Stage | Single |
|---|
Efficiency
| AFUE | 80% |
|---|
Electrical
| Voltage | 120 V |
|---|---|
| Phase | 1 |
| Frequency | 60 Hz |
| Maximum fuse or breaker | 15 A |
| Minimum circuit ampacity | 6.8 A |
Airflow
| Airflow | 1230 CFM |
|---|
Physical
| Depth | 28.38 in |
|---|---|
| Height | 33.00 in |
| Width | 14.50 in |
| Weight | 111.00 lb |
Rated 4.7 / 5 Stars
4700+ Verified Reviews
Comfort That Speaks for Itself
See why homeowners and pros alike trust MRCOOL DIY systems to deliver comfort, savings, and easy installation.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.
I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!
Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency
Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.
I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.
Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.
Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!
I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.