Having commercial HVAC equipment is often a necessity for any business, but how do you know if you are getting the most out of your system? By measuring the live operating efficiency of a commercial HVAC system you can diagnose and prescribe solutions much more efficiently. In this article we’ll look at how to measure commercial HVAC system efficiency:
When you measure the efficiency of your HVAC unit, it will allow you to understand whether or not you need a replacement or a professional cleaning. Measuring both the output of a commercial heating and cooling system, as well as its performance can be difficult. Once you learn how to measure the efficiency of your heating and air conditioning system it will be hugely beneficial.
Understand Commercial Efficiency Ratings (How to Measure Commercial HVAC System Efficiency)
You may have heard of SEER (Seasonal Energy Efficiency Ratio) or AFUE (Annual Fuel Utilization Efficiency), commercial systems are measured a bit differently. Commercial systems are rated with CSER (Cooling System Efficiency Rating). This commercial rating is based on how the system performs in a real-life situation. This is measured by a certified technician in a laboratory and indicates the absolute potential efficiency of the equipment.
Rather than allow contractors to sell systems based on the “measured” efficiency, or promised generic efficiency, the commercial efficiency rating tells you how it will operate in the field.
How is CSER Measured?
The Cooling System Efficiency Rating, is a measured ratio of the BTU delivered into a building after installation. This number is then divided by the rated BTU of the equipment in the laboratory. This eventually gives you a percentage in which you can understand the level of its operation,
Most often, the average commercial HVAC system only operates at a field measured efficiency of 56%. What may be more surprising, is that the typical code-compliant system only operates at 63% CSER. This may make you wonder at which level is your commercial HVAC system performing?
BTUs
Commonly referred to as BTUs, this acronym stands for “British Thermal Unit”. Essentially, a BTU is a scientific unit of heat needed to heat a pound of water by one degree Fahrenheit.
Another method of measuring a BTU is to compare it to the heat that is output by a standard wooden match. The best way to accurately measure BTUs that are being put out by your HVAC systems is with a simple mathematical calculation. This will allow you to understand how efficient your heater or cooling equipment.
1. Locate the voltage (in volts), current (in amps), and/or wattage (in watts) of the device you wish to measure. The instruction manual of the unit or a label on the device itself should list these measurements.
2. Calculate the wattage of the device by multiplying the volts by the amps. For example, if the device has a voltage of 160 volts and a current of 2 amps, its wattage would be 320 watts (160 times 2). Divide the result by 3.413 — a constant figure — to determine the BTUs per hour. The example of 320 watts divided by 3.413 to get 93.76 BTUs per hour.
3. Multiply the BTUs per hour by the number of hours the device runs to determine its total BTU output. To continue the above example, if the device runs for 6 hours, it will generate 562.56 BTUs in that period of time (562.56/6 hours=93.76 BTU). The BTU output measures how much heat or other energy a given appliance is generating and is useful when determining if a unit can heat a given space.
Non-Technical – Measure Commercial HVAC System Efficiency
When looking at how to measure commercial HVAC system efficiency, you can do so by looking at the airflow. The airflow will be able to show how much air has been warmed, as well as cooled, and when that air reaches different parts of the building.
Although this is not a technical method, it can give you a good idea of if you would like to pursue more testing of your commercial HVAC unit. Listen to the air vents and understand where the air is flowing from. You may be able to see how much energy is behind it and decide if you need to have a technical test done to confirm. Another not technical method to understand HVAC performance and to see if your HVAC system is energy efficient is to measure the temperature change. This can be done by seeing how quickly the temperature goes down or up after the system has been turned off. For a large business, it can be difficult to use the above methods to measure the efficiency of your HVAC system. If you still are not convinced to obtain a CSER test, then you can monitor your energy costs instead. If you notice that your energy costs rise, then it means your HVAC system is not working as efficiently as it should be. The last resort (non-technical) method for measuring your HVAC system is to visually observe the furnace, heat pump, or whichever area is responsible for the temperature. You should check the output time, as well as the length it runs, and regularity.
This will allow you to understand if the system is running more often or for longer periods than it typically does. If this is the case, then you should understand that it is running inefficiently.
Are You Concerned if Your HVAC System is Running Efficiently?
Overall, testing is essential to understanding the efficiency of your HVAC system. Although monitoring your HVAC system and its output will allow you to understand your energy star efficiency, you may need to go the extra step.
At Rahn we can offer help to learn about HVAC systems, maintenance, and repair services that can offer increased efficiency. We offer the ability to measure your CSER, and visually see it in numbers. Contact us today.
Contact us today by calling (800) 421-7070 to learn which solution will work best for you and your business.[/vc_cta][/vc_column][/vc_row]