Direct Fired Heaters
Direct fired heaters are similar to a gas barbecue grill or your gas stove top. With propane or natural gas heating, units force air directly through the flame to heat the air.
Benefits to using direct fired heaters include:
- Efficiency – Direct fired heaters convert 100% of the fuel being used to direct heat which lowers fuel consumption and operating Costs
- Easy to Transport – Direct fired heaters are fairly simple pieces of equipment that can be moved to where heat is needed
- Powerful – High amounts of heat (BTU’s) are produced in smaller units when compared to indirect fire heaters
- Some units do not require electricity
- Lower rental costs – Direct Fired Heaters are less expensive
- Lower Maintenance Costs – Easier to maintain
- Built in thermostat – On most models a thermostat is used to control temperature
- Safe for unsupervised use – Multiple redundant safety features allow direct fire heaters to stay running without supervision. Priority Rentals heaters are CSA and UL rated.
Some drawbacks to using direct fired heaters are:
- Ventilation Required – The room must have some level of air exchange. Direct fired heaters cannot be used in a tightly sealed structure unless windows and doors can be opened for air exchange.
- Adds moisture and carbon monoxide into the air.
Indirect Fired Heaters
Indirect fired heaters are just like your home oil or gas burning furnace with a chimney. With propane or natural gas heating units, the flame is contained in a burn chamber which heats a “heat exchanger”. The cooler air passes over and around the heat exchanger, thus heating the air. You can learn more about indirect heaters and watch us install one in an older post.
Indirect fired heaters offer some positive points, like:
- 100% clean, dry air – The air being circulated never comes in direct contact with the flame.
- Built in thermostats – Almost all indirect fired heaters use a thermostat
- Can operate in tightly sealed spaces – Indirect fired heaters do not release carbon dioxide into the space.
Some negative aspects about indirect fired heaters are:
- Higher Cost – The rental cost is nearly quadruple that of direct fired
- Lower Efficiency – Fuel efficiency is usually close to 80%
- Electricity Required – Indirect fired heaters always need an electrical outlet
- Requires exhaust ventilation – You must either vent the exhaust outside or duct the hot air inside. This makes installing and removing indirect heaters cumbersome because of the set up and tear down of duct work.
- Hard to transport – Indirect fired heater units are much larger and less portable.
Direct and indirect fired heaters are used for specific applications. Generally, direct fired heaters are used on construction sites, outdoor applications, or warehouses. On the other hand, a work space that is tightly sealed and lacks a working heating system is an ideal setting for a indirect heater.
At Priority Rental, we offer a broad variety of direct and indirect fired heaters for rent or purchase. For a more general overview of the heaters we offer, visit our portable heaters page.