Duluth Forge FDF400T-ZC-R Gas Fireplace Insert

What you get

The Duluth Forge FDF400T-ZC-R Gas Fireplace Insert is a gas insert that its maker rates at 32,000 BTU per hour and says heats up to 1,500 square feet.

Treat the 1,500 square feet as the maker's best case for an open, reasonably insulated space, and check it against your room before choosing.

At full fire it burns about 31 cubic feet of natural gas or about 0.35 gallons of propane an hour (its 32,000 BTU/h divided by EIA's heat content for each fuel).

As a vented unit it sends its exhaust outside through the vent system its manual lists, so it leaves room air alone; the vent route has to suit the house.

Fuel, per the listing: dual fuel. Never connect a gas heater to a fuel it isn't set for.

Also on the listing: overall dimensions of 15 in (D) x 29 in (W) x 29 in (H) and ceramic construction.

The figures, from the maker

Each figure is the maker's or the listing's own, with its source marked. A figure the maker doesn't give is shown as not stated.

Model number	FDF400T-ZC-R	Retailer
Power	Gas Powered	Retailer
Dimensions (seller)	15"D x 29"W x 29"H	Retailer
Material	Ceramic	Retailer
Mounting / installation	Built In	Retailer
Heat output (maker)	32,000 BTU/h	Retailer
Features (seller)	Adjustable Thermostat	Retailer
Model name	FDF400T-ZC-R	Retailer
Heats up to (maker)	1,500 sq ft	Retailer
Venting	Ventless	Retailer
Fuel	dual fuel	Retailer
Thermostat	Thermostat	Retailer

Is it the right heater for the room?

Pick it when

Clean-venting room heat
Homes with gas or propane

Pass on it when

Homes without a vent route
Homes without gas or propane

Where it wins, where it gives ground

Wins

32,000 BTU/h
Exhaust vented outside
dual fuel

Gives ground

Needs a vent route
Needs a gas line

Know before you install

Figures are the maker's own and are rated in the maker's conditions. Installation, venting, chimney, gas and electrical work follow the manual and local code, carried out by a qualified installer.

Heaters to weigh against it

Duluth Forge FNF300T Gas Fireplace InsertHeats up to 1,350 sq ft.

Duluth Forge FLF300T Gas Fireplace InsertHeats up to 1,350 sq ft.

ProCom PCS150T Gas Fireplace InsertHeats up to 800 sq ft.

Other gas stoves, fireplaces and inserts in the same heat range

Every gas stoves, fireplaces and inserts on one chart · All Duluth Forge models listed

Buying this model

The button opens this exact model's listing. Prices and stock change, and installation parts are usually sold separately; check the box contents and the manual's venting list before you order.

Prices change often; the button shows today's price.

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Questions about this model

How much gas does the Duluth Forge FDF400T-ZC-R Gas Fireplace Insert use?

At full fire, about 31 cubic feet of natural gas or about 0.35 gallons of propane an hour, from its 32,000 BTU/h rating and EIA's heat contents; lower settings use less.

Does the Duluth Forge FDF400T-ZC-R Gas Fireplace Insert need a vent or chimney?

Yes: it vents outside through the system its manual lists.

Bottom line

Pick it for clean-venting room heat.