2) Consider Control Settings
Before the heating season starts, verify the typical operating schedules for all departments or groups in the building, Daily recommends.
“Sit down with them and say ‘Does this AHU actually need to run from 6 a.m. to 6 p.m.? Do you need it seven days per week or five?’” explains Daily. “Verify everything. The more you shut it down, the more you save.”
Also examine how well you’re pressurizing the building, Daily recommends.
“When you walk into the building, do you feel wind coming from inside that’s blowing out the front door, or do you feel it being drawn in when you open the door? Do you hear a whistling?” Daily says. “That means there’s a differential in there. What should happen is a slight positive pressure on the building so you’re bringing in a little outside air.”
3) Check Equipment Function
Confirm that the newly cleaned equipment is fully functional, starting with ensuring that equipment actually shuts off or powers down as scheduled when it enters an unoccupied mode.
“Check the air handling unit and make sure the exhaust fan shuts down as well. If you shut off the AHU and don’t bring in much air, the exhaust fan is going to suck air out of the building and it will be made up by air coming in through infiltration,” says Daily. “We worked with a school that had been drawing 30,000 cubic feet per minute into the building since 1971 because of the AHU design. It was plagued with frozen pipes and high heat bills, mainly due to exhaust fans running more than necessary during unoccupied hours.”
One easy trick to check the exhaust involves circling the building with your car when you arrive at work in the morning.
“Look for plumes of steam on the vents and places where everything is covered with ice except for one place where there’s water,” Daily explains. “No snow is an indication that an exhaust fan ran all night long and melted the snow.”
4) Identify Operational Inefficiencies
Using a steam system? Look for escaping vapor – you could be losing condensate, resulting in overspending. Between water and energy expenses, each gallon of lost condensate can end up costing you $3-4, explains Daily.
“Condensate loss is a compounded loss. You paid for the water to come in and paid for it to leave, even though it left as a vapor,” Daily says. “You also paid for the heat to put it into the boiler the first time, you paid the heat losses when it was delivered, and you lost the heat that you could have returned to the boiler when you lost the condensate.”
Getting your heating system up to speed isn’t a one-time job – add HVAC inspection and optimization tasks to your regular preventive maintenance schedule if they’re not there already. Otherwise, you may not be getting the most efficient performance from your HVAC system, Daily adds.
“If you budget $1,000 per month for energy during the winter and you consistently come up at $900, the finance guys are going to be very happy that you were under budget, but did you really optimize the system?” Daily asks. “Did you get the true value on your operation, or did you just meet the budget price?”
Janelle Penny firstname.lastname@example.org is senior editor of BUILDINGS.