Is your heating equipment ready to roll when cold weather settles in?
Even if there was no trouble last year, the system likely needs a thorough once-over. These four tips from HVAC experts will help you plan this year’s tune-up.
1) Assess Initial Damage, Dirt, and Risk
Start by cleaning and repairing the system and anything that affects its operation. Places that may need some extra elbow grease include:
Envelope: If your building’s envelope hasn’t been inspected recently, now is a good time to find and treat any leaks or places where outside air can infiltrate, such as windows and unsealed doors.
Pipes: In some places, like heat runs behind a school auditorium or near the overhead door in a storage area, your piping may be subject to freezing. Check to ensure insulation hasn’t been damaged and add, repair, or replace as necessary.
“A simple half-inch wrap on exposed piping can save you roughly 50 BTUs per hour per linear foot on hot water heating systems,” notes Bernie Daily, president and practitioner of Daily Operations Inc.
Equipment: Your heating equipment likely needs a tune-up before it’s put into daily use for the winter, says Tony Mori, service field superintendent and project manager for FM provider Crockett Facility Services.
“Bringing boilers or hot water heaters online is mostly a checklist operation – turning everything on, making sure all the nuts and bolts are tight, and looking for gas or water leaks,” Mori explains. “Problems could include dirty filters if you have an oil- or gas-based system and injector nozzles on oil-powered equipment.”
One client whose system hadn’t been cleaned found more than dirt and grime in the heating equipment, adds Diane McClelland, Crockett’s marketing director.
“We’ve had strange things happen, like stinkbugs and mice in the systems that people didn’t clean,” McClelland notes. “While those things don’t prevent the equipment from operating, it may not run as efficiently. People may not even realize there’s a problem.”
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.