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HVAC (Heating, Ventilation & Air-conditioning)

HVAC (pronounced either ‘H-V-A-C” or “H-VAK”) is an acronym that stands for
“heating, ventilation and air-conditioning.” Often installed into a single system, these three
functions of the HVAC system are closely interrelated to provide thermal comfort and to
maintain good indoor air quality. HVAC is sometimes referred to as climate control because
it provides heating, cooling, humidity control, filtration, fresh air, building pressure control,
and comfort control.

HVAC is one of the largest consumers of energy in the hospitality industry,
constituting approximately 30 percent or more of total costs. HVAC systems that operate
properly are essential in lodging facilities and contribute to employee productivity and guest
satisfaction.

Because HVAC systems account for so much electric energy use, almost every
facility has the potential to achieve significant savings by improving its control of HVAC
operations and improving the efficiency of the system it uses through proper design,
installation and scheduled maintenance. The following sections outline some important
components of the HVAC system as well as offer suggestions to improve your facility’s
efficiency.

It is recommended that you schedule maintenance on your heating and air
conditioning systems twice annually by a licensed HVAC contractor. Although some
maintenance jobs can be accomplished inexpensively using in-house staff, others may
require calling an outside technician. These maintenance and system checks are important to
maintaining the performance of your system, similar to changing the oil in your vehicle
every 3,000 miles. The HVAC tune-up should do the following:


Replace air filters regularly: Accumulated dirt and dust make your fans work
harder. Clean filters help system performance, increase equipment life and help
reduce allergens in your building.
Clean heat-transfer coils in heat pumps, air conditioners and chillers: Make sure
that leaves and plants are not obstructing outdoor coils and have any bent coils
straightened. In addition to saving energy, this will also increase the capacity of your
system.
Inspect ducts and piping for leakage and missing or damaged insulation:
Insulation is especially important in unconditioned spaces and leaky ductwork is one
of the biggest contributors to cooling loss in buildings.
Make sure that furniture or other obstructions do not block air flow around
radiators, convectors or air intakes and diffusers.
Identify any areas in your facility that are unused but are being conditioned:
Consider turning off the HVAC to these areas or closing the vents.
Have your fuel-fired boiler or furnace checked out at least annually, before the
heating season starts: Have the technician check the combustion efficiency and
report the results along with any suggestions for improving boiler efficiency.

1. Get an HVAC Tune-up

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5. INVEST IN A PROGRAMMABLE THERMOSTAT

Although night-setback and temperature-setpoint changes are simple enough to be
done manually, an automatic control is much more efficient and reliable. Electronic,
programmable thermostats allow you to program in desired setpoint and cutoff times for a 7-
day week. Be sure to place the thermostat in a location where the temperature is

The most clear-cut method to save on your HVAC bill is to simply operate your
system less. This can be done either by turning the system off or setting it back when the
building or building section is not occupied. Setting back your thermostat means changing
the temperature setting (setting back to a lower temperature).

For example, a week contains 168 hours. If your business operates during 40, or
even 80, of those hours, you occupy your facility during only a fraction of the week. You
can minimize your HVAC usage by turning down your HVAC settings in all or some of
your building during unoccupied hours.

3. TURN OFF OR “SET BACK” THE HVAC SYSTEM

If the fan on the thermostat is left in the “on” mode, it runs nonstop 24 hours per day.
In “auto” mode, the fan runs on only when heating or cooling is being supplied. Even if
temperature setback changes are minimal, fan adjustments can be significant. If your system
draws in ventilation air from outdoors, cycling the fan on “auto” can also help with humidity
control.

4. TURN THE FAN SWITCH ON THE THERMOSTAT TO “AUTO” RATHER THAN “ON.”

2. CHOOSE MORE EFFICIENT TEMPERATURE SET POINTS

Substantial savings are also available by adjusting your temperature setpoints —
lower setpoints in the winter and higher temperature setpoints in the summer. Make the
changes gradually, no more than one degree per week, to see how low (or high) a setting you
need to maintain a comfortable facility. Try to make the changes without announcing them
to your staff to avoid complaints about temperature change before employees can actually
feel the difference. This can also help to identify an appropriate comfort level for
your facility.

Repair old valves and steam traps: A steam trap costs about $50.00. If broken it
can waste hundreds of dollars each winter. Some suppliers estimate that anywhere
from 20 - 60 percent of traps nationwide have failed. Failed steam traps not only
waste money and energy, but they also cause extreme occupant discomfort.
Inspect and oil fan motors: Replacing older or failed motors with more fficient
models can result in significant savings.

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6. ENERGY MANAGEMENT SYSTEM (EMS)

Approximate Percentage Savings From Thermostat Setback


Region Setback Temperatures
60° F 55° F 50°F

Mid- to Northern
Michigan & U.P. 5-7% 9-15% 14-22%

Southern
Michigan 7-9% 15-19% 22-28%


*Savings based on 65° F and assuming setback for 14 hours/weeknight and all weekend
Source: "Reducing Energy Costs Means a Better Bottom Line." National Frozen Foods
Association/U.S. Department of Energy

representative of the entire area served by the system—not next to the air-conditioning, heat
vent, drinking fountain, computer or other electronic equipment. Many businesses find it
worthwhile to install a locking enclosure around their thermostats to avoid unauthorized
tampering with the setpoints. The table below summarizes potential savings from
thermostat setback.

Programmable thermostats are effective and work quite well, especially with
individual-unit air conditioners and heaters. If your facility uses larger, central systems such
as boilers and chillers, you may wish to use an energy management system (EMS). These
systems are capable of controlling many different functions in a building. Some automatic
control features include:


Adjustment of supply-air temperatures based on indoor and outdoor temperature and
humidity to let heating and cooling systems operate most efficiently


There may be times when you need cooling in the building but the outside temperature
is low. With an economizer mode, your system can circulate outdoor air for free
cooling during these periods.


Implementation of holiday period automatic setpoint adjustments


Automatically adjust air intake and temperature based on occupancy


Monitor space temperatures to minimize overheating or overcooling of spaces in a
zone-by-zone basis


An EMS can be used to control other functions in your building as well, such as
lighting, fire suppression and security. It can manage your electric loads, prevent peak loads
and optimize your electrical rate with your electric utility.

EMS suppliers typically estimate that an EMS can cut the heating and cooling bills
of a business with a central chiller and heating system by 10 to 50 percent, with many
estimates clustered around the 20 percent range.

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