80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace
SKU MGM80SE045A3A
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Description
80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace
What's in the Box
Here's what you'll receive with your order
80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas F...
As described
Key Specifications
120V
Voltage
44,000BTU
Heating Capacity
80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace — Model Details
What this specific model is sized for, how it installs, how it performs, and what it costs to run.
Room & Space Coverage — 44 BTU
The 80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace delivers 44 BTU of cooling and heating capacity (3-ton class), sized for spaces up to 450 sq ft in standard 8-ft ceiling rooms with average insulation. At this capacity the unit targets small rooms, nurseries, tiny homes, enclosed porches, and dedicated zones that need precise temperature control without oversizing — oversized units short-cycle, which hurts humidity control and shortens compressor life.
Efficiency & Operating Cost
On the gas side the unit achieves 80% AFUE, meaning 80¢ of every fuel dollar becomes usable heat — the rest exits through the flue.
Power & Electrical Requirements
Power requirement: 120V 1-phase 60Hz (standard US 120V household outlet). Minimum circuit ampacity is 6.8A with a maximum overcurrent protection of 15A. Wire the outdoor unit with 14 AWG copper on a dedicated 15A double-pole breaker (or single-pole at 120V), with a disconnect within sight of the condenser per NEC 440.14.
Install Difficulty — Professional Install
This is a professionally-installed condenser that requires a licensed HVAC technician with EPA 608 certification. The tech will pull a vacuum on the line set to 500 microns, pressure-test with nitrogen, release the factory charge, and commission per MrCool's startup procedure. Budget 1 full day for install on a single-zone system.
Sound Level & Comfort Features
The indoor blower offers 5 fan speeds plus auto mode, letting you trade airflow for quiet operation in bedrooms while running louder in living areas.
What's in the Box & Compatibility
Ships as a Gas Furnace.
Product Details
When harsh winter weather strikes, nothing compares to the warmth and safety a powerful reliable gas furnace can provide. While furnace heating technology has been around for decades, not all systems are created equally. Some are definitely better than others. One of the best on the market is the MRCOOL single stage, 80% AFUE gas furnace. This system can be installed upflow or horizontal, and is designed to operate for decades, provide powerful heating capability, and best of all, keep your heating bill affordable at the same time. It does the latter via its 80% AFUE energy efficiency rating. That mark of quality ensures 80% of every dollar you spend on heating fuel gets turned into real, effective heat for your home.
Specifications
| Heating Capacity | 44 BTU |
| Voltage | 120 V |
| Tonnage | 3 Ton |
| Airflow | 1230 CFM |
| Phase | 1 |
| Country of Origin | Mexico |
Features
- Removable floor base for bottom return air
- Easily removable slide out blower design
- Left or right utility connections
- Zero step horizontal conversion
- Aluminized steel inshot burners for smooth ignition
- Multi-speed high efficiency (constant torque) blower motor
- AHRI Certified
- Aluminized steel tapered crimped non-welded clam shell heat exchanger design
- Heating efficiency of 80% AFUE
- Registered 10-year parts warranty
Frequently Asked Questions
Everything you need to know about this product
What size room will the 80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace cool?
Do I need a licensed HVAC installer?
What electrical circuit do I need for installation?
How fast does HVACZAR ship this unit?
What if it arrives damaged or I change my mind?
What is the warranty on the 80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace?
How long does shipping take?
What size room does 44 BTU cover?
Do you offer returns?
How can I pay?
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Ships Nationwide — Shop by State
We deliver the 80% AFUE 3 Ton 45,000 BTU Upflow/Horizontal 5-Speed Gas Furnace to all 50 states via FedEx, UPS, and truck freight. Each state page lists local rebate programs and utility incentives.





