FAQs

Cambridge Engineering’s technical services specialists answer thousands of questions a year. Here we've collected some of the most frequently asked questions and their responses. If you can't find an answer to your question here, please contact your Cambridge Client Care Specialist for assistance.

What are 'direct gas-fired' heaters?

The burner fires directly in the air stream being heated rather than through a heat exchanger. This results in no wasted energy by these types of commercial heating units and 100% of available energy is delivered to the heated space because no flue or heat exchanger is required. 

What are HTHV heaters and what are their benefits?

High Temperature Heating and Ventilation (HTHV) heaters have a discharge temperature of greater than 150°F and a temperature rise of greater than 140°F.

The High Temperature (HT) discharge provides the maximum Btu per CFM, delivering more usable heat and less outside air to the space. 

Are all direct gas-fired air heaters alike?

NO, selecting the wrong direct gas-fired heating solutions can result in higher installation costs and higher operating costs.

Isn't a Btu a Btu when comparing different gas-fired heaters?

For Blow-Thru and draw-thru heating solutions with the same input capacity, a Blow-Thru™ heater delivers: 
  • More useable heat to the space
  • Less outside air to the space

How can heating 100% fresh air with Cambridge® heaters be efficient?

All heating systems must heat outside air entering the building via natural infiltration. Cambridge commercial heating units manage infiltration by supplying more Btu per cfm than other heating systems. Additionally, with Cambridge® heaters there is no flue loss as with other indirect-fired equipment.

Do direct gas-fired heaters create humidity and condensation problems?

No, actual building studies show that Cambridge direct gas-fired heaters can help solve humidity problems, not cause them.

What is the benefit of the S-Series and SA-Series Blow-Thru® design?

These commercial heating units attain 160°F discharge temperature. The Blow-Thru design also extends component life by mounting all critical parts in a cooler environment that is out of the hot air stream.

How does Cambridge get that much heat out of such a small S-Series HTHV Heater?

Our proprietary Blow-Thru design achieves 160°F temperature rise/discharge temperature and requires less space between the burner and blower.

What's the big deal about 160°F discharge temperature?

It is the industry's highest rating for this type of space heating equipment and allows us to deliver the maximum amount of heat with the minimum amount of outside air. The maximum 160°F discharge temperature rating is crucial because it translates into lower horsepower motors, less outside air and reduced energy costs.

Will 160°F discharge air stratify?

Due to our high velocity discharge air, we are able to drive the heat to the floor resulting in a rapid mixing with surrounding air. Floor to ceiling variation typically does not exceed 3° F to 7° F. Our Building Study Program has confirmed this with real data at existing Cambridge installations.

How does Cambridge get even temperature distribution?

By utilizing a combination of discharge velocity, discharge volume, air displacement and heater location.

Will Cambridge HTHV heaters blow hot air directly on people?

No, not directly. Cambridge heating solutions mix high volumes of ambient air which rapidly cools the high discharge air temperatures. Also, directional elbows can be redirected to adjust airflow.

Why doesn't Cambridge recirculate existing building air?

The Cambridge design with high temperature rise/discharge and intermittent operation, delivers the maximum useable heat without the need for re-circulation. This reduces the potential build-up of contaminated building air. Therefore, the non-recirculating Cambridge® S-Series Space Heater is both safer and more energy efficient than "80/20" recirculation type systems.

How can Cambridge S-Series HTHV Heaters be competitive against conventional unit heaters?

Simply compare the total installed cost of both heating systems:
• Equipment cost
• Equipment installation
• Gas piping
• Electrical wiring
Or compare operation costs:
• Want to know how to conserve energy as well as lower your heating costs? There's a 20% to 50% energy savings per year with Cambridge

How does Cambridge compare to indirect gas-fired Air Turnover (Air
Rotation) heating systems?

If you are still using indirect gas-fired recirculation heating solutions it is time to reconsider your options. Cambridge heaters are up to 70% more energy efficient, have a lower first installed cost and can
eliminate stratification problems associated with air rotation units used in warehouses with high ceilings.

What is the Cambridge Warranty?

The quality of the warranty and the company that stands behind it are what is really important. Our unit warranty is 2 years. The S-Series & M-Series stainless steel burners and ITH-Series emitter tube heat exchangers all carry a 5-year warranty.

Does Cambridge offer factory design assistance?

Yes - Cambridge takes the time to learn how to conserve energy in your building, specifically. Take advantage of our 50 years experience calculating heat loads and let us help design the most effective and energy efficient heating system for your building. Our proprietary Cal-Q-Heat® Program has become an industry standard for heat load calculations associated with warehouses, distribution centers, manufacturing plants, aircraft hangars, indoor recreational facilities, automobile service areas and other large commercial/industrial buildings.

The Cal-Q-Heat® form can be downloaded from our website, filled out and faxed or emailed to Cambridge or your local representative.

Click Here to download Cal-Q-Heat® PDF file.

Are Cambridge heaters recommended for LEED/Green buildings projects?

Yes - Cambridge Engineering is an Energy Star Partner, an active member of the U.S. Green Building Council (USGBC) and Cambridge heaters are compliant with ASHRAE Standard 90.1-2004, a requirement for all LEED buildings.

What is infrared radiant heating and how does it save energy?

Infrared radiant heaters work like the sun’s rays that heat the earth. Radiant energy from overhead infrared heaters is absorbed by the building’s floor that warms up and then releases its stored heat to raise the building’s ambient air temperature. Infrared heaters provide additional warming and spot heating for people and objects that directly absorb their radiant energy. Infrared radiant tube heaters use less energy to keep people comfortable compared to unit heaters and other types of indirect gas-fired space heaters.

What makes a good gas-fired infrared radiant heater?

Energy efficiency, performance, reliability, safety, fast installation and low maintenance are the hallmarks of a good infrared heater. These attributes are a function of heater design and using high quality components. It starts with the reflector’s efficiency. All Cambridge ITH-Series infrared radiant tube heaters have the industry’s best 99% efficient reflector to maximize the amount of radiant energy that reaches the floor.

Are Blow-Thru Space Heaters more energy efficient than Infrared Radiant Heaters?

Only Cambridge offers both Blow-Thru® commercial heating units and Infrared Radiant Heaters, the two most widely accepted energy efficient technologies for heating commercial and industrial buildings with open spaces. Comparison building studies and energy modeling show Cambridge Blow-Thru Space Heaters are more effective in reducing total energy costs for large insulated buildings and offer the added benefit of improving indoor air quality. Cambridge ITH-Series Infrared Heaters can be a cost effective way to provide focused energy efficient heat for spot heating applications in large buildings. Combination heating systems using infrared radiant heaters with larger capacity direct gas-fired Blow-Thru space heaters or make-up air units can be an energy efficient, cost effective solution for many buildings. Factory trained Cambridge sales engineers will help you design the best, lowest total cost heating system for your application.