Description
MHI MTA925 Process Air/Gas Heater (4kW). This is a one-atmosphere sealed system for heating various non-combustible gases.
Dimensions are about 18″ long and 5.5″ in diameter.
Exit: Threaded exit nozzle 2″ NPT Male.
Inlet: Threaded inlet nozzle 1/2″ NPT Male.
When selecting a flowmeter please indicate the type of gas in the remarks column.
Continuous Hot Air/Gas Discharge up to 925°C (Nominal for Air with 60C input and maximum power).
The maximum temperature limit is 950°C. Maximum power varies with socket voltage. Please see below.
Flow Rate and Temperature: At 4KW power Air or Nitrogen: Typically ~ 6.5 SCFM for 925C for Air. About 10 SCFM for CO2.
Maximum Power: 4 kW Total Power (Nominal @ 240V). This is the power at 240 V supply conditions. If the supply is 208 V please note you will only obtain a maximum of ~3.3 KW.
For 230 V the power draw will be ~3.9 KW.
Stainless Steel Shell Construction. ~1 Atmosphere use only.
Built-In “K” Type Process Thermocouple
Plug-In Design. Use 208/220/230 or 240V. 50/60Hz. Wiring to unit provided (wall connection plug is local scope)
Ready to Use. This Airtorch® is for use only for non-combustible gases and non-reacting gases like Air, Nitrogen, Argon, and mixtures of non-reacting gases. Input gas should not exceed ~60C.
Unit is sold only for non-combustible, non-pressurized, and non-ignitable/non-reactive gases and mixtures.
If using for steam or steam mixture please indicate in the remarks column during check out. Only dry noncondensing input steam-gas are allowed.
The Optional Mixer Nozzle provides gas inlets at the Airtorch® exit. Optional Mixer Nozzle (see picture). Three-way input. The nozzle is insulated with insulation for 1400C.
Full Power and Flow Controller Options Available
Independent Power and Flow Control Available (optional).
BPAN-O-PLUS models have temperature and over-temperature control. Choose UL or cUL for the Canada option for BPAN if required.
For MTA models when the inlet flow is pressure-driven, the flow rate is often pre-set by an appropriate SCFM flow meter.
The minimum flow rate should be maintained. MHI BPAN-O-PLUS power controllers can be used to set temperature and/or power.
- * Please note that mass flow meters are recommended when operating above 900C. Float gas type gas flow meters if used must be used with the float valve indicator that is accurate in the 7 -16 SCFM for operations close to the maximum rated temperature. Float gas meters are not as accurate ass mass flow meters.
- * Please note that the shipping price is an estimate and normally quoted only for US shipping. Your acknowledgment may contain an amended shipping price that reflects a more accurate price for the shipping.
- Model: MHI Model# MTA925-04
Temperature: 925°C Maximum Continuous (Minimum airflow to be maintained). Temperature measured by internal TC before nozzle exit. Exit temperatures are highly dependent on the application and use conditions.
Thermocouple: Built-in K-type thermocouple. Can be linked for external display (TC-READ) or full control (BPAN Control Panel).
Element Installation: Factory installed. Heating elements can only be serviced at MHI approved location, where applicable. Please contact your MHI sales representative for service program and details.
Wiring Requirements: 240 Volt, single-phase @ 50/60Hz, 18 Amp Max current. May be used with 208V or 230V or 220V input. Maximum power will vary with line voltage.
Power Consumption: 4 kW (Nominal @ 240V). Slightly lower power and temperature for 220V.
Frequency: 50/60 Hz
Air-Source: Via compressed air source or compressed gas source (e.g. Nitrogen / Argon). Approximately ~6.5 SCFM is the minimum airflow (compressed air) required when operating the device at full power to achieve maximum temperatures. A compressed air source is not included and is within the user’s scope. Please contact MHI for assistance.
- Gas Source: User Scope. Not to exceed 60°C at the inlet.
Inlet: 1/2″ NPT Male. Inlet gas not to exceed 60°C
Outlet: 2” NPT Male
Optional:
Power Control: Optional: MHI BPAN™ or BPAN-O-PLUS-220 Control Panel. Single Phase Controller. Includes on-off switch, thermocouple readout, and PID controller. Advanced phase angle fired SCR with soft start and current limiting features integrated for device protection and control. BPAN -O-PLUS-220 has an over-temperature controller. Display: Either BPAN-O-PLUS Control Panel or Not included. The built-in thermocouple can be linked for external display on optional product TCREAD basic display. Optional: 3 ½ LCD display switchable between °C and °F
Flow Control: Optional: FLM flow meter for basic flow control of pressure flow. Setting range suitable for 4kW. Please indicate Gas in the remarks column. SCFM readings.
Controls: Can I use my own? Generally not an issue if you have experience. Please ensure that you have over temperature cut off and soft start features like the BPAN-O-PLUS offers. This is particularly important when using close to the maximum rated temperatures. Please note that sealed units cannot be repaired if a burn out occurs. There is no warranty on the heaters when used with non-MHI controls or if control features are disabled.
With the BPAN-O-PLUS a cUL or UL option is also offered.

BPAN-UL
Efficiency. Flow chart to consider https://mhi-inc.com/airtorch-design-graphs/. It is a general guidance chart not specific to your device. Also there could be small variations of the nominal resistance or air flow provided by flow meters (even mass flow meters).
Can I use it in a hot enclosure? The temperature of the outside cannot be more than 80°C
MHI Airtorch™
L.S. Distinguished Senior Tech at National Laboratory, USA
You are the Best! Thank you very much for your support.
R.S. Ohio
“We purchased the 10kW Airtorch™ to perform rapid cycling tests to qualify our product for a new customer. We have secured the contract and the Airtorch™ is still going strong for 2 years. We are now using it for new development projects.”
See use picture
J.M. of Morgan Tool
“Using the LTA as the primary heat source for my customer’s tool turned out to be a wise decision. It’s robust for continuous use in a shop floor environment.”
C.A., UK (International)
I am very satisfied with the Airtorch™; we operate it everyday between 1100 and 1200°C for our experiments.
EL, National Lab, USA
“I really like the LTA … very much. They are incredible! As per my calculation, we are seeing (very high) efficiency…”
Nate M, Utah
“We added the 15kw Airtorch to our existing Gas Tunnel Kiln to improve uniformity and overall drying time. It was cheaper than buying a new kiln”
Paul F, Pennsylvania
“We’ve used the Airtorch™ as a pre-heater for our application. It works well, we bought two…”
Ron J, Ohio
Finally, a product for die heating that really meets our needs!”
Tim D, Ohio
“Airtorch™ is a great concept, it works well for my unique applications…”
Ken F, Tennessee
“This hot air device offers great versatility, its the device I’ve been waiting for…”
Jim V, Michigan
“This device will save us money.”