Mr. Heater MH400FAVT 400,000 BTU

Last updated: October 30, 2026

Mr. Heater MH400FAVT 400,000 BTU
3.1/5#12 of 18 in forced air propane heaters
3.1

For large construction sites, barns and warehouses that need heat on an industrial scale from a bank of 100 lb tanks. Use it only with plenty of fresh air.

  • 250,000 to 400,000 BTUHeat output
  • Job sites and garagesUse
  • None publishedSafety listing
  • 1 yearWarranty
Check price at Amazon$665.84

Price checked October 30, 2026. As an Amazon Associate we earn from qualifying purchases.

Pros
  • 400,000 BTU, enough for a 10,000 sq ft building by Mr. Heater’s figure
  • Holds a set temperature on its thermostat
  • Turns down to 250,000 BTU
  • Hose and regulator included
Cons
  • Needs at least two 100 lb propane tanks
  • No safety listing, flame-out or tip-over shutoff named on the product page
  • Heavy at 56 lb and costs over $650
  • Not indoor-safe by Mr. Heater’s own spec: job sites and ventilated work buildings only

How it scores

The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its type. How we rank explains each one.

Specifications

Model numberMH400FAVT (F272425)
Heating
Heat output250,000 to 400,000 BTU
TypeForced air
UseJob sites and garages
Heats up to10,000 sq ft
ThermostatYes
FanYes
Fuel and power
FuelBulk tank
Hose includedYes
IgnitionElectric
Power needed120 V outlet
Safety
Safety listingNone published
Build
Dimensions21.9 x 38.6 x 14.8 in
Weight56.4 lb
Warranty1 year
Released2010-01

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