FanmasterJuly 18, 2023

Should You Use Direct Fired Or Indirect Fired Diesel Space Heaters?

When it comes to heating large spaces or outdoor areas, diesel space heaters are a popular choice due to their efficiency and reliability. However, selecting the right type of diesel space heater is crucial to meet your specific heating needs.

Let’s explore the differences between direct-fired and indirect-fired diesel space heaters, helping you make an informed decision for your heating requirements.

Direct-Fired Diesel Space Heaters

Direct-fired diesel space heaters are designed to deliver heat directly into the desired area. They operate by burning diesel fuel within a combustion chamber, generating hot air that is then distributed through a fan. These heaters are commonly used in well-ventilated spaces such as construction sites, warehouses, or outdoor events.

Benefits Of Direct-Fired Diesel Space Heaters


These heaters are more fuel-efficient compared to their indirect-fired counterparts since there is no heat loss through heat exchangers.


Direct-fired heaters are often compact and lightweight, making them easily transportable between different locations.

Fanmaster Direct Fired Diesel Heater

Fanmaster Direct Fired Diesel Heater



Direct-fired heaters require adequate ventilation due to the combustion process, ensuring proper airflow and preventing the build-up of potentially harmful emissions.

Moisture And Dust

Since direct-fired heaters introduce outdoor air directly into the heated space, they may bring in moisture and dust, which can be a concern in certain applications.

Indirect-Fired Diesel Space Heaters

Indirect-fired diesel space heaters work differently from direct-fired heaters. They employ a heat exchanger to separate the combustion process from the heated air. The heater burns diesel fuel in a separate combustion chamber, and the resulting heat is transferred to clean, dry air that is circulated within the target area.

Benefits Of Indirect-Fired Diesel Space Heaters

Fanmaster Indirect Diesel Heater

Fanmaster Indirect Diesel Heater

Clean And Dry Air

Indirect-fired heaters provide clean, dry heat without introducing combustion by-products, moisture, or exhaust fumes into the heated space.


These heaters can be used in various settings, including construction sites, warehouses, tents, and temporary structures, as they do not require external ventilation.


Heat-Up Time

Indirect-fired heaters may have a slightly longer heat-up time compared to direct-fired heaters since the heat is transferred through a heat exchanger.


Indirect-fired heaters may have slightly lower fuel efficiency due to heat loss through the heat exchanger. However, this can be mitigated by using high-efficiency models.

Choosing The Right Diesel Space Heater For Your Needs

Consider the environment, ventilation, and air quality when assessing the specific heating requirements. Determine if portability is necessary and evaluate efficiency based on expected runtime and fuel consumption.

Prioritise safety by complying with regulations and addressing specific concerns. These considerations will guide you in selecting the right diesel space heater.

Get in touch with Fanmaster to learn more.

Should You Use Direct Fired Or Indirect Fired Diesel Space Heaters? / Fanmaster