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Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 250,000 BTU, Model# MHU250

Item# 103065
"Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 250,000 BTU, Model# MHU250"
Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 250,000 BTU, Model# MHU250

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Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 250,000 BTU, Model# MHU250

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$1999.99

  • Shipping: 

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    Heavy/large item. Lift gate service available.

  • Store Pickup: 

    Not Available
  • Requires only 1in. clearance from ceiling with threaded rods (sold separately)
  • Spark Ignition with self diagnostic control module
  • 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
  • Ships as Natural Gas unit

See full description

Complete Your Solution

  • Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 250,000 BTU, Model# MHU250
  • Thermostat For Mr. Heater Garage Heaters
Price for all two:

$2024.98

Frequently Bought Together

  • Description

  • Key Specs

  • Reviews

  • Q & A

  • Accessories

  • Warranty

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Product Summary

This Mr. Heater Big Maxx™ Natural Gas High-Output Commercial Unit Heater is quiet and vented for easily heating a large 8400 sq. ft. building. The low-profile design requires only 1in. clearance from the ceiling and delivers 250,000 BTU output. Easily installs using 3/8-16 threaded rods (sold separately). CSA certified. Check local codes and ordinances for approved installation and usage. Works with Thermostat Item# 173641 (sold separately).

What's Included

    (1) Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater -- 250,000 BTU, Model# MHU250

Downloads

Product Manual

Features + Benefits

  • Requires only 1in. clearance from ceiling with threaded rods (sold separately)
  • Spark Ignition with self diagnostic control module
  • 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
  • Ships as Natural Gas unit
  • Easy external access for thermostat connections and AC terminals
  • Compatible with WiFi/Digital thermostats (not included)
  • Power exhaust with 6in. flue allows for vertical or horizontal venting (Category 1 Vertical and Category 3 Horizontal venting, kits sold separately)
  • Max mounting height of 18ft. from floor to bottom of heater (18in. clearance from side, rear, and corner walls) * 1/2in. gas connection
  • Thermostat sold separately -- Item# 173641
  • Check local codes and ordinances for approved installation and usage -- See product manual for venting and electrical supply requirements
  • Can be converted to LP using Item# 5261103 (sold separately)
  • Physical appearance of the MHU250 may vary from what is shown, but will fit all required venting

Key Specs

AttributeSpecification

item#

103065

Brand

Mr. Heater

Manufacturer's Warranty

3 year limited warranty

Ship Weight

195.0 LB

Heat Output

250,000 Btu/hour

Heat Type

Forced Air

Heating Capability

8,400 ft²
AttributeSpecification

Needs Direct Venting

Yes

Blower Included

Yes

Blower CFM

3,435 cfm

Thermostat Included

No

Volts

120

Product Weight

180 lb

Dimensions L x W x H (in.)

41.3 x 28.7 x 24.8

Reviews

Questions & Answers

11 Reviews This action will navigate to reviews.

Questions

1–10 of 14 Questions  
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  1. Any idea on fuel consumption for this unit? When switched to LP?

    1 answer

    1. The Big Maxx heater will use approximately 1 pound of propane per hour when operating at full capacity.

      Helpful?

  2. How many amps does it take to run this heater and can it be converted to propane 

    1 answer

    1. This heater is equipped with a 3 amp fuse. The propane conversion kit, part #MHF260170, is available through our sister company, Jacks Small Engines. Please visit www.JacksSmallEngines.com for pricing and availability.

      Helpful?

  3. what is the gas pressures requirements on inlet of heater?( what do we need to reduce natural gas pressure to for this unit?)

    1 answer

    1. The propane inlet pressure should be 7" water column (W.C). The natural gas inlet pressure should be 11" water column (W.C).

      Helpful?

  4. Does it require a line volt or low volt thermostat?

    1 answer

    1. This heater can be used with either a 24V low Voltage or Millivolt thermostat.

      Helpful?

  5. Can it be put on a stand

    1 answer

    1. This heater cannot be put on a stand. It is designed to be mounted with the proper clearances. Please reference the product manual underneath the product summary for more information on mounting/clearances.

      Helpful?

  6. Can’t this heater be converted to propane 

    1 answer

    1. The heater can be used with propane or natural gas.

      Helpful?

  7. Does this come with any mounting hardware? If not, what type of hanging brackets are recommended?

    1 answer

    1. The heater would include the mounting brackets.

      Helpful?

  8. How large of a uninsulated will this heat

    1 answer

    1. For an uninsulated building, the 250,000 BTU heater would heat up to approximately 6,250 square feet.

      Helpful?

  9. Would this be safe for a wood working shop that has sawdust?

    1 answer

    1. This is not an explosion proof heater. This heater may not be used in a Class 1 or Class 2 Explosive Environment. A wood working shop would be considered a Class 2 Explosive Environment as the sawdust has the potential to become flammable or ignitable.

      Helpful?

  10. Can you vent this unit to attic(above the steel ceiling) in a post frame building? Does it need to go out thru the roof?

    1 answer

    1. This can be vented through the wall or roof, and may only be vented outdoors. The vent kits items 104400 and 104401 are available to order.

      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

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 High-Output Commercial Unit Heater, 250,000 BTU, Model# MHU250
4.5 out of 5 stars. 11 reviews

Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 250,000 BTU, Model# MHU250

Item # 103065

$1999.99