The Hotline Newsletter

Summer 2004

Cambridge Space Heaters versus Unit Heaters

It's hard to compare a Cambridge S-Series Space Heater to other types of heaters. The technology is so unique that there is really "Nothing Else Like It" for heating commercial and industrial buildings.

High Efficiency Cambridge Space Heaters

Most contractors, engineers, facility managers and building owners are familiar with gas-fired unit heaters so we are often asked the following questions:

How do you compare to unit heaters?
Answer: How big is your building?
Cambridge S-Series Heaters offer lower total cost, improved indoor air quality and more balanced temperatures throughout the building for space heating applications that require multiple unit heaters installed around the perimeter of a building. In other words, if your space heating application is over 10,000 sq. ft. or requires more than four unit heaters, you should give us a call.

Is Cambridge space heating technology more energy efficient?
Answer: Yes.
Indirect gas-fired unit heaters typically are only 60% to 75% seasonally efficient. Higher fuel bills result from the energy loss that escapes up the flue and from wasted heat that rises to the ceiling. Cambridge direct gas-fired space heaters, with no flue or heat exchanger, deliver 100% of BTUs to the heated space. They can reduce energy costs by 30% to 50%. That translates into significant annual cost savings as shown in the comparative building study.

What about installation costs?
Answer: You would be surprised.
One powerful Cambridge Space heater often replaces 4 to 10 unit heaters. This will dramatically reduce installation costs.

Are buildings with high ceilings a problem?
Answer: No.
Unit heaters with propeller fans have a very low velocity air throw and must be mounted near the floor to be effective. One rule-of-thumb is that unit heaters can lose 2% efficiency for every foot of mounting height over 15 feet. However, the high velocity discharge air of Cambridge Blow-Thru® space heaters make them an ideal choice for high bay manufacturing and warehouse facilities where heaters are mounted 25 to 50 feet above the floor.

Can Cambridge heaters solve my negative building air and indoor air quality problems?
Answer: Yes.
Most unit heaters provide no building ventilation with fresh outside air. They just re-heat and re-circulate contaminated indoor air. When an exhaust system is used, the building is starved for make-up air (MUA). This creates a constant path of cold air drafts when dock doors open or renders the exhaust system ineffective when the building is closed up tight. Indoor air quality (IAQ) problems can then occur in negative pressure buildings and flue gas can back draft into the facility. Replacing the unit heaters with Cambridge non-recirculating, direct gas-fired space heaters can help solve all these problems and even reduce operating costs.

Are there other advantages of using Cambridge Space Heaters?
Answer: Yes.
Low hanging unit heaters mounted around the perimeter of a building for circular airflow often do not focus heat where it is most needed at cold dock doors. They also "get in the way", are easily hit by forklift trucks and can consume valuable vertical racking space. Fewer, but more powerful, Cambridge Space Heaters can be installed just about anywhere in the building to solve all these problems.

Unit Heater Problems