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Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 300,000 BTU, Model# MHU300

Item# 103066
"Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 300,000 BTU, Model# MHU300"
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Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 300,000 BTU, Model# MHU300

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Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 300,000 BTU, Model# MHU300

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$2299.99

  • Shipping: 

    Available now

    Heavy/large item. Lift gate service available.

  • Store Pickup: 

    Out of stock at Fredericksburg VA

  • 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, 300,000 BTU, Model# MHU300
  • Thermostat For Mr. Heater Garage Heaters
Price for all two:

$2324.98

Frequently Bought Together

  • Description

  • Key Specs

  • Reviews

  • Q & A

  • Accessories

  • Warranty

  • Compare

Product Summary

This Mr. Heater Big Maxx™ Natural Gas High-Output Commercial Unit Heater is quiet and vented for easily heating a large 10,000 sq. ft. building. The low-profile design requires only 1in. clearance from the ceiling and delivers 300,000 BTU output. Easily installs using 3/8-16 threaded rods (sold separately). CSA certified. Works with Thermostat Item# 173641 (sold separately).

What's Included

    (1) Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater -- 300,000 BTU, Model# MHU300

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# 5261120 (sold separately)
  • Physical appearance of the MHU300 may vary from what is shown, but will fit all required venting

Key Specs

AttributeSpecification

item#

103066

Brand

Mr. Heater

Manufacturer's Warranty

3 year limited warranty

Ship Weight

245.0 LB

Heat Output

300,000 Btu/hour

Heat Type

Forced Air

Heating Capability

10,000 ft²
AttributeSpecification

Blower Included

Yes

Blower CFM

4,507 cfm

Thermostat Included

No

Volts

120

Product Weight

227 lb

Dimensions L x W x H (in.)

41.3 x 28.7 x 24.8

Reviews

Questions & Answers

3 Reviews This action will navigate to reviews.

Questions

1–10 of 11 Questions  
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  1. How much propane does this burn in an hour?

    1 answer

    1. Model MHU300 is designed to run on natural gas, not propane. At its 300,000 BTU/hr rating, the heater will consume about 3 therms per hour, roughly 290–300 cubic feet of natural gas per hour, which is approximately 8.3 cubic meters per hour.

      Helpful?

  2. Do you have to vent if converted to LP?

    1 answer

    1. This heater will still need to be vented if converted to LP.

      Helpful?

  3. I need the BTU input Rating for my gas company 

    1 answer

    1. The BTU input is 300,000 BTU per hour.

      Helpful?

  4. How do I get a propane kit for this heater?

    1 answer

    1. The propane conversion kit for this heater is part #F260171. This is available through the manufacturer.

      Helpful?

  5. can this unit be direct vented out the wall

    1 answer

    1. This can be vented through the wall or ceiling.

      Helpful?

  6. where is this made

    1 answer

    1. The heater is manufactured in Italy.

      Helpful?

  7. Gas company is asking for the load in cfh for this unit

    1 answer

    1. This measurement would be 120 CFH for propane and 286 CFH for natural gas.

      Helpful?

  8. What natural gas pressure is needed to operate this furnace ?

    1 answer

    1. This will require a supply pressure of 7 to 20 W.C. for natural gas. Propane use will require a supply pressure of 11 to 20 W.C.

      Helpful?

  9. What is an appropriate propane tank size to purchase for this product

    1 answer

    1. The heater will require a 100 pound tank or larger to operate.

      Helpful?

  10. How long is warranty on heat exchanger

    1 answer

    1. The heat exchanger in this unit has a 10-year warranty from the manufacturer.

      Helpful?

Accessories We Recommend

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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

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Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 300,000 BTU, Model# MHU300
5.0 out of 5 stars. 3 reviews

Mr. Heater Big Maxx Natural Gas High-Output Commercial Unit Heater, 300,000 BTU, Model# MHU300

Item # 103066

$2299.99