Modine PTP250 Horizontal Power-Vented Natural Gas Unit Heater - 250,000 BTU, 115V, Aluminized Steel

250,000 BTU Commercial Unit Heater With 6-Inch Venting, 3,995 CFM, And 62-Foot Heat Throw. A Natural Gas Power Vented Industrial Heater For Large Warehouses, Factories, And Commercial Spaces

The Modine PTP250 (PTP250AS0111) is a 250,000 BTU commercial gas unit heater built for large commercial and industrial spaces that demand high-output heating with 6-inch power-vented exhaust. At 250,000 BTU input and 205,000 BTU output (82% efficiency), it pushes 3,995 CFM with a 47°F temperature rise, throws heat 62 feet from a maximum mounting height of 18 feet, and handles horizontal vent runs up to 100 feet.

The Modine PTP250 unit heater replaces the legacy Modine PDP250 with significant upgrades: a tubular heat exchanger with in-shot burners for more efficient combustion, a 409 stainless steel heat exchanger option for greenhouses and corrosive environments, in-cabinet controls protection that shields wiring and ignition components from dust and moisture, and a contractor convenience box with diagnostic LEDs. 

Quick Specs

• BTU Input: 250,000

• BTU Output: 205,000 (82% efficiency)

• Airflow: 3,995 CFM at 70°F

• Supply Voltage: 115V, 1-Phase, 60 Hz

• Vent Size: 6 inch

• Gas Connection: 3/4 inch

• Maximum Mounting Height: 18 ft

• Heat Throw: 62 ft at max mounting height

• Dimensions (D x W x H): 33.83 x 42.53 x 31.31 inches

• Weight: 265 lbs

Key Features

• 250,000 BTU with 3,995 CFM and 62-foot throw: This 250,000 BTU commercial gas unit heater delivers high-volume airflow across large open floor plans. The 62-foot heat throw from an 18-foot mounting height covers warehouses, factories, and industrial bays that smaller units cannot reach.

• 6-inch power-vented exhaust: The PTP250 uses a 6-inch vent pipe with a factory-installed power exhauster that handles horizontal runs up to 100 feet. This is the vent tier for large commercial buildings where the heater may be far from an exterior wall or roof penetration.

• 3/4-inch gas connection: Sized for the higher gas volume that 250,000 BTU requires. Ensures consistent fuel delivery at full-rated input without pressure drop across longer gas supply runs.

• Modern replacement for the PDP250: The PTP250 replaces Modine's legacy PDP series with a tubular heat exchanger and in-shot burners (the PDP uses a drum-style exchanger). This design delivers more consistent heat transfer and longer exchanger life. Modine rates the PTP as "Better" versus the PDP's "Good."

• 409 stainless steel heat exchanger available: Standard aluminized steel handles most commercial environments. The stainless option (PTP250SS0111) is rated for greenhouses, agricultural buildings, and spaces with corrosive atmospheres. Both carry a 10-year heat exchanger warranty.

• In-cabinet controls protection: Controls, power exhauster, and ignition components are housed inside the cabinet, shielded from airborne dust, moisture, and debris. The PDP does not offer this.

• Contractor convenience box: Built-in on/off toggle switch, green power indicator, yellow call-for-heat indicator, terminal board for low-voltage wiring, and supply conduit knockouts. Diagnostic LEDs speed up troubleshooting on-site.

• Low-profile horizontal design: Ceiling or wall mount in commercial spaces with limited overhead clearance. The 42.53-inch width fits standard joist bays.

• Converts to propane: Ships natural gas. Modine kit #55406 converts to LP. The same burner is used for both fuels.

• Cold climate rated: Starts reliably down to -40°F. ETL certified for commercial and industrial use in the US and Canada. CSA-B149.1 compliant.

Modine PTP250 Natural Gas Commercial Unit Heater Specifications

Available Options

Fuel Type:

• Natural Gas (standard)

• Propane (via field conversion kit #55406)

Ignition Type:

• Single-Stage, Direct Spark Ignition, 100% Shut-Off with Continuous Retry (standard)

• Two-Stage, Direct Spark Ignition (optional, fires at 100% and 50% of rated input)

Heat Exchanger Material:

• Tubular, Aluminized Steel (standard, this model: PTP250AS0111)

• Tubular, 409 Stainless Steel (optional, model: PTP250SS0111, rated for greenhouses and corrosive environments)

Fan Configuration:

• Propeller Fan (PTP series, this model)

• Centrifugal Blower Fan (BTP series, for ducted applications)

Performance Overview

The PTP250 delivers 3,995 CFM at a 47°F temperature rise with a 721 FPM outlet velocity, producing 205,000 BTU of usable heat output. From its 18-foot maximum mounting height, it throws heat 62 feet across the floor. The 6-inch power exhauster handles horizontal vent runs up to 100 feet, giving contractors flexibility in large buildings where exterior walls are far from the heating zone. 

As a natural gas power vented industrial heater rated at 250,000 BTU, the PTP250 replaces the Modine PDP250 with better combustion efficiency and protected controls. It is the 250,000 BTU commercial unit heater built for facilities that need 6-inch venting and long vent runs.

Why the PTP250 Replaces the PDP250

Modine designed the PTP series as the modern successor to the PDP. If your facility currently uses a PDP250 and it is due for replacement, the PTP250 is the direct upgrade. Here is what changed:

Same 250,000 BTU input, same 6-inch vent pipe, same gas connection. The PTP250 drops into a PDP250 install with improved internals and serviceability.

Included with the PTP250 Unit Heater

• Adjustable horizontal air deflector blades

• Factory-installed power exhauster (6-inch)

• Contractor convenience box (toggle switch, diagnostic LEDs, terminal board)

• Gas control step-down transformer (24V)

• Fan delay timer

• Auto-reset limit control

• Differential pressure switch (proof of venting)

• Installation and service manual

Not included (sold separately):

• Vent pipe and fittings (6-inch diameter required)

• Vent cap (Modine PN 5H0722850002 for PTP250-400)

• Thermostat (any standard 24V thermostat)

• LP conversion kit (Modine #55406)

• Gas supply piping and shutoff valve (3/4-inch)

• Deflector hoods (30, 60, and 90-degree available)

• Vibration isolation kit

• Two-point suspension kit

Applications

• Large warehouses and distribution centers (5,000 to 8,000+ sq ft)

• Manufacturing floors and factory bays

• Greenhouses and agricultural buildings (stainless steel heat exchanger recommended)

• Auto dealership service departments and fleet garages

• Aircraft hangars (minimum 10 ft above the highest wing or engine surface)

• Loading docks and freight terminals

• Fire stations and municipal equipment buildings

Installation Tips

• Commercial and industrial use only. The PTP series is ETL certified for commercial and industrial applications. It is not certified for residential use.

• 6-inch vent pipe required. The PTP250 requires a 6-inch vent pipe and a 3/4-inch gas connection. If you are upgrading from a 4-inch-vented unit, you will need a new vent pipe, a new vent cap (Modine PN 5H0722850002), and a 3/4-inch gas line. Plan for these infrastructure changes before ordering.

• Max 100-foot horizontal vent run. Each 90-degree elbow adds equivalent length. Minimum 3-foot vent run required. The 6-inch vent allows longer runs than the 4-inch models (50-70 ft max).

• Replacing a PDP250? The PTP250 uses the same 6-inch vent pipe, the same gas connection size, and fits the same mounting footprint. No vent or gas line changes needed when upgrading from PDP to PTP.

• LP kit is #55406. The same burner is used for both natural gas and propane.

• High altitude derating. For elevations above 2,000 feet, reduce ratings by 4% per 1,000 feet above sea level.

• Clearances: 6 inches on all sides (top, bottom, access, non-access). 18 inches at the rear. Minimum 7-foot install height from floor. In aircraft hangars, a minimum of 10 feet above the highest wing or engine surface.

Buy the Modine PTP250 Commercial Gas Unit Heater Online from Cleanflow

The PTP250 is the best 250,000 BTU commercial unit heater for facilities that have outgrown 4-inch-vented heaters and need serious coverage. With 3,995 CFM, a 62-foot throw from 18 feet, and 100-foot vent runs, it handles the large open spaces that drive warehouse and factory heating decisions. If you are replacing a PDP250, the PTP250 fits the same vent and gas infrastructure with upgraded internals. 

Cleanflow Utility Supply Company stocks the PTP250 gas unit heater with free shipping on orders over $199 CAD across Canada and the USA. As an authorized Modine supplier, Cleanflow backs every unit with manufacturer warranty support. Not the right fit? Cleanflow offers hassle-free returns and exchanges on all orders.

Frequently Asked Questions

What is the difference between the PTP250 and the PDP250?

The PTP250 is Modine's modern replacement for the legacy PDP250. Both are 250,000 BTU commercial gas unit heaters with 6-inch venting. The PTP250 upgrades to a tubular heat exchanger with in-shot burners (the PDP uses a drum-style exchanger), adds a stainless steel heat exchanger option, includes in-cabinet controls protection, and comes with a contractor convenience box with diagnostic LEDs. Modine rates the PTP as "Better" and the PDP as "Good." Same vent pipe, same gas connection, better internals.

Does the PTP250 require a 6-inch vent pipe?

Yes. The PTP250 uses a 6-inch vent pipe and a 3/4-inch gas connection. This is a step up from the smaller PTP models (150-200) that use a 4-inch vent and 1/2-inch gas. If you are installing fresh, plan for 6-inch vent materials. If you are replacing a PDP250, the existing 6-inch vent pipe works.

How does the Modine PTP250 compare to the Mr. Heater Big Maxx 250,000 BTU?

Both are 250,000 BTU commercial gas unit heaters. The Modine PTP250 features a tubular heat exchanger with in-shot burners, in-cabinet controls protection, a contractor convenience box with diagnostic LEDs, and a 10-year heat exchanger warranty (including greenhouse use). The PTP250 also offers a 409 stainless steel heat exchanger option. Both are power-vented and ETL certified. The PTP250 unit heater is designed, engineered, and assembled in the USA.

Will 250,000 BTU heat my warehouse?

At 250,000 BTU input (205,000 BTU output), the PTP250 handles approximately 5,000 to 8,000+ square feet, depending on insulation, ceiling height, and climate zone. The 62-foot heat throw from an 18-foot mounting height covers large open floor plans. For very large facilities, multiple units or a larger PTP model (300-400 MBH) may be needed.

Is the PTP250 unit heater rated for cold climates like Canada?

Yes. Starts at -40°F. ETL certified for commercial and industrial use in the US and Canada. CSA-B149.1 compliant. At 250,000 BTU, it provides substantial heating capacity for large commercial spaces in extreme cold. For elevations above 2,000 feet, derate by 4% per 1,000 feet.