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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 80,000 BTU, Model# MHU80NG

Item# 27465
"Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 80,000 BTU, Model# MHU80NG"
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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 80,000 BTU, Model# MHU80NG

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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 80,000 BTU, Model# MHU80NG

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$599.99

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  • Power exhaust allows for vertical or horizontal venting
  • Designed for right or left side piping, electrical and flue connections by simply rotating 180°
  • Tubular heat exchanger and spark ignition
  • 6 Amp draw
  • Horizontal venting kit, Item# 29794, and vertical venting kit sold separately

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  • Description

  • Key Specs

  • Reviews

  • Q & A

  • Accessories

  • Warranty

  • Compare

Product Summary

This Mr. Heater Big Maxx™ Natural Gas Garage/Workshop Unit Heater is quiet and vented for easily heating a 2- to 3-car garage. The low-profile design requires only 1in. clearance from the ceiling (two angle brackets are included). Big Maxx features power exhaust for vertical or horizontal venting. Use right or left side piping, electrical and flue connections by simply rotating 180°. Big Maxx includes an aluminum tubular heat exchanger for maximum efficiency and longer life. Handy extras include spark ignition with a self-diagnostic control module and easy outside access to the thermostat and AC terminals. Works with Thermostat sold separately, Item# 173,641. Note: Installation requires an 8ft. clearance from the floor and will not pass code with less than 8ft.

What's Included

    (1) Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, Model# MHU80NG, (1) LP conversion kit

Downloads

Product Manual

Features + Benefits

  • Power exhaust allows for vertical or horizontal venting
  • Designed for right or left side piping, electrical and flue connections by simply rotating 180°
  • Tubular heat exchanger and spark ignition
  • 6 Amp draw
  • Horizontal venting kit, Item# 29794, and vertical venting kit sold separately
  • Thermostat sold separately -- Item# 173641
  • Includes LP conversion kit
  • Note: Due to BTU loss through exhaust gases, heater runs at approx. 81% operating efficiency
  • Note: Installation requires an 8ft. clearance from the floor and will not pass code with less than 8ft.
  • Note: Check local codes and ordinances for further approved installation and usage

Key Specs

AttributeSpecification

item#

27465

Brand

Mr. Heater

Manufacturer's Warranty

3 year limited warranty

Ship Weight

88.0 LB

Heat Output

80,000 Btu/hour

Heat Type

Forced Air

Heating Capability

2,000 ft²
AttributeSpecification

Blower Included

Yes

Blower CFM

950 cfm

Thermostat Included

No

Volts

120

Product Weight

88.0000 lb

Dimensions L x W x H (in.)

30.31 x 22.04 x 27.55 in

Reviews

Questions & Answers

584 Reviews This action will navigate to reviews.

Questions

1–10 of 128 Questions  
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  1. Is the 80,000 BTU input or output?

    1. This heater has a 64,000 BTU output.

      Helpful?

    2. page 2 of the owners manual PDF states 80k btu input, 64k btu output.

      Helpful?

    3. Per the manual it's 80K BTU input with an 80% efficiency so output is 64K BTU.

      Helpful?

    4. The owners manual says this unit is 80,000 btu input, and 64,000 btu output

      Helpful?

  2. Where is the exhaust port? Top? Side? Back?

    1. Back

      Helpful?

    2. Back. And its 4 inch.

      Helpful?

    3. The exhaust port is located on the back of the heater.

      Helpful?

    4. It comes out the back.

      Helpful?

  3. Can fan be utilized by itself?

    Can the unit blow air as controlled from a thermostat? Such as heat: on/off via temp setting and air: auto/on?

    1. Yes, with the proper stat and wire it can be used in fan only.

      Helpful?

    2. Yes, it has a extra terminal to hook up to the thermostat for this, just as a normal residential unit does.

      Helpful?

    3. This heater could be used with the fan on and no heat provided you have a thermostat with a fan only option.

      Helpful?

  4. Can the Mr. heater (80,000 btu) model be vented horozontally using properly rated pvc pipe?

    1. No, can't use pvc pipe at all

      Helpful?

    2. This Mr. Heater Big Maxx Natural Gas Garage/Workshop Heater can only be vented horizontally using stainless steel. It cannot be vented using rated PVC pipe.

      Helpful?

    3. Thank you for your inquiry. No, it can only be vented horizontally with stainless steel.

      Helpful?

  5. What amp service is needed for this heater ?

    Looking at installing this heater in my 3 car garage and want to make sure I have the correct circuit protection. There is no in the heater instruction.

    1. 15 amp

      Helpful?

    2. The MHU units only need a 110 line to run the heater.

      Helpful?

    3. The amp draw for the blower motor at start-up will require a 15 Amp fuse as it will pull 13 to 14 amps.

      Helpful?

  6. Will this work with a Nest thermostat?

    1. Yes

      Helpful?

    2. The Nest thermostat will work with this Mr. Heater Big Maxx heater. Detailed instructions are provided in the owner's manual.

      Helpful?

  7. Do I need a Thermostat with it?

    1. This heater will operate with the on/off switch without a thermostat. If you want to leave the heater on and keep the area at a desired temperature, you will need to install a thermostat. Northern Tool offers item 173641.

      Helpful?

    2. This heater will operate with the on/off switch without a thermostat but if you want to leave the heater on and keep the area at a desired temperature, you will need to install a thermostat. Northern does carry one for this unit. See below.

      Helpful?

  8. how far of a run can the exhaust be

    I have a warehouse that is only open to the outside in the front. can the exhaust be ran say 75 feet horizontally?

    1. no, 25' max

      Helpful?

    2. The venting cannot be run 75 feet because the maximum allowance is only 25 feet of venting, and for every elbow used the maximum length must be lessened by 5 feet per each elbow.

      Helpful?

  9. Is this heater supposed to be hardwired?

    Or does it come pre-wired with a cord? If so how long is the cord?

    1. It should be hardwired in on a dedicated breaker with a disconnect switch close to the unit.

      Helpful?

    2. This unit must be hardwired. It cannot be plugged into an outlet.

      Helpful?

  10. Does this unit require and external gas pressure regulator

    1. Thank you for your inquiry. Yes, this unit requires and external gas regulator.

      Helpful?

    2. An external gas pressure regulator is required for this heater.

      Helpful?

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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.

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Mr. Heater Big Maxx Natural Gas Garage/Workshop Unit Heater, 80,000 BTU, Model# MHU80NG
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