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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 125,000 BTU, Model# MHU125NG

Item# 57328
"Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 125,000 BTU, Model# MHU125NG"
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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 125,000 BTU, Model# MHU125NG

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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 125,000 BTU, Model# MHU125NG

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$999.99

  • Shipping: 

    Free shipping (lower 48 states) - Available now

    Heavy/large item. Lift gate service available.

  • Store Pickup: 

    Not Available
  • Requires only 1" clearance from ceiling with 2 included angle brackets
  • Power exhaust allows for vertical or horizontal venting
  • Designed for right or left side piping, electrical and flue connections by simply rotating 180°
  • Aluminum tubular heat exchanger for maximum efficiency and longer life
  • Spark ignition with self-diagnostic control module

See full description

Complete Your Solution

  • Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 125,000 BTU, Model# MHU125NG
  • Thermostat For Mr. Heater Garage Heaters
  • DuraVent Vent Unit Heater Kit, 4in. Horizontal, Model# 4UHK-KVNT
  • Mr. Heater 225,000 BTU, 2-Stage Regulator, Model# F273863
Price for all four:

$1497.96

Frequently Bought Together

  • Description

  • Key Specs

  • Reviews

  • Q & A

  • Accessories

  • Warranty

  • Compare

Product Summary

This Big Maxx™ Natural Gas Garage/Workshop Unit Heater is designed for residential and commercial use, easily heating a 2- to 3-car garage. Built-in electric high velocity fan pulls cool air into the rear of the heater and over a heat exchanger, forcing hot air into the surrounding area. Item may come in Dark Gray or Tan. Works with Thermostat Item# 173641 (sold separately). Note: Installation requires an 8ft. clearance from the floor and will not pass code with less than 8ft.

What's Included

    (1) Big Maxx Natural Gas Garage/Workshop Unit Heater

Downloads

Product Manual

Features + Benefits

  • Requires only 1" clearance from ceiling with 2 included angle brackets
  • Power exhaust allows for vertical or horizontal venting
  • Designed for right or left side piping, electrical and flue connections by simply rotating 180°
  • Aluminum tubular heat exchanger for maximum efficiency and longer life
  • Spark ignition with self-diagnostic control module
  • Easy outside access to thermostat and AC terminals
  • Requires 115 Volt AC power
  • Includes LP conversion kit
  • 4" flue for both horizontal and vertical venting; venting kit required (not included)
  • Thermostat, Item# 173641, sold separately
  • Note: Installation requires an 8ft. clearance from the floor and will not pass code with less than 8ft.

Key Specs

AttributeSpecification

item#

57328

Brand

Mr. Heater

Manufacturer's Warranty

3 year limited warranty

Ship Weight

112.0 LB

Heat Output

125,000 Btu/hour

Heat Type

Forced Air

Heating Capability

4,167 ft²
AttributeSpecification

Needs Direct Venting

Yes

Blower Included

Yes

Blower CFM

1,475 cfm

Thermostat Included

No

Product Weight

89.1000 lb

Dimensions L x W x H (in.)

25.0 x 26.58 x 25.67 in

Reviews

Questions & Answers

114 Reviews This action will navigate to reviews.

Questions

1–10 of 52 Questions  
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  1. whats the efficiency percnetage of gas

    whats the efficiency percnetage

    1. It is an 80% efficiency unit which means you loose 20% through the vent exhaust. This is actually really good for this type of unit. The older units would loose 60% which means you loose more than your heating.

      Helpful?

    2. This Big Maxx natural gas heater has an 80% efficiency rating.

      Helpful?

  2. any info on the running dB?

    1. This unit is quiet. Due to lack of industry standards on decibel ratings, the manufacturer does not have a rating.

      Helpful?

    2. I am not sure of the dB's but this unit is quiet. I was very pleased how quiet it was.

      Helpful?

  3. Is there a LP Conversion Kit

    1. Yes, there is. I converted mine to LP and it was easy. You had to switch out the orifices and the spring inside the regulator/valve. There is good directions in the manual included with your unit.

      Helpful?

    2. The LP conversion kit is included with this heater.

      Helpful?

  4. Is this product suitable for installation/use in a damp location? (Car Wash with no direct water contact, but definitely humid. Need to replace a a 22 year old Dayton.

    1 answer

    1. The heater is not designed or approved to be installed in a damp or wet location.

      Helpful?

  5. Do I need a regulator with naturalgas

    1 answer

    1. A low pressure regulator is required for natural gas.

      Helpful?

  6. can this unit be set on its bottom on a wood deck 10ft from the floor

    1 answer

    1. This heater cannot operate sitting on a wood deck. It does minimally require 8 ft. of clearance at the bottom of the heater.

      Helpful?

  7. is this heater available for propane?

    1 answer

    1. This unit comes with a LP conversion kit.

      Helpful?

  8. Is this CSA certified?

    1 answer

    1. The heater is CSA International design certified. The installation must conform with local building codes or in the absence of locals codes with the current CSA B 149.1 (natural gas and propane installation code). All electrical wiring and grounding for the unit must comply with the Canadian Electrical Code CSA C22.1.

      Helpful?

  9. Will the universal Mr heater vertical vent kit f102849 fit ?

    1 answer

    1. The 6" vent kit, model F102849 would not work with this garage heater. It would use the 4" vertical kit, model 4GVKNT, item #28795.

      Helpful?

  10. What size Allthread is needed to hang this unit?

    1 answer

    1. The hanging bracket would have 1/2" NPT threads.

      Helpful?

Accessories We Recommend

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See All Thermostats
Thermostat For Mr. Heater Garage Heaters
3.5 out of 5 stars. 91 reviews

Thermostat For Mr. Heater Garage Heaters

Item # 173641

$24.99
See All Venting
DuraVent Vent Unit Heater Kit, 4in. Horizontal, Model# 4UHK-KVNT
4.4 out of 5 stars. 39 reviews

DuraVent Vent Unit Heater Kit, 4in. Horizontal, Model# 4UHK-KVNT

Item # 29794

$429.99
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Mr. Heater 225,000 BTU, 2-Stage Regulator, Model# F273863
4.8 out of 5 stars. 40 reviews

Mr. Heater 225,000 BTU, 2-Stage Regulator, Model# F273863

Item # 25819

$42.99

Warranty

Manufacturer's Warranty

3 year limited warranty

Extend Your Warranty Coverage with a Northern Protection Plan (NPP)

Repair Plan — 1 Year

A Northern Protection Plan is available after adding the product to your shopping cart.

Recently Viewed Items

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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 125,000 BTU, Model# MHU125NG
4.8 out of 5 stars. 114 reviews

Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 125,000 BTU, Model# MHU125NG

Item # 57328

$999.99