For commercial property owners and facility managers in Des Plaines and Mount Prospect, October is the last good window to get heating equipment ready. The first cold snap always brings a rush of no-heat calls from warehouses, shops, offices, churches, and multi-unit buildings, and parts like ignition controls, inducer motors, and circulator pumps can be backordered right when you need them. A structured heating-season startup reduces that risk, catches safety issues, and keeps tenants and employees comfortable.
This checklist covers the main commercial heating systems we service across the northwest suburbs: rooftop units with gas heat, unit heaters, commercial boilers, and make-up air units.
Why a Fall Startup Matters
- Safety: Cracked heat exchangers, blocked flues, and failed safeties can produce carbon monoxide.
- Reliability: Equipment that sat all summer often has seized dampers, dead igniters, or nests in the flue.
- Efficiency: Dirty burners and poor combustion waste gas every hour the unit runs.
- Budget planning: Finding a failing boiler in October gives you time to plan a replacement instead of paying emergency rates in January.
Rooftop Units (RTUs) With Gas Heat
- Replace filters and check belts, pulleys, and blower bearings
- Inspect heat exchanger for cracks, rust-through, or scorching
- Clean burners and verify flame characteristics
- Test igniter, flame sensor, and gas valve operation
- Verify inducer motor and pressure switch operation
- Test high-limit and rollout safeties
- Measure gas pressure and temperature rise against the nameplate
- Check economizer dampers so they don’t stick open and freeze coils
- Seal cabinet panels and check curb gaskets for water and air leaks
Gas-Fired Unit Heaters
Common in warehouses, garages, and shops, unit heaters are often forgotten until they fail.
- Clean heat exchanger and burners; remove dust and debris
- Check vent pipe and termination for blockages and proper clearances
- Test ignition and safety controls
- Inspect fan motor, blade, and guard
- Verify thermostat operation and location (thermostats near dock doors cause short cycling)
Commercial Boilers (Hot Water and Steam)
- Inspect combustion chamber and flue passages; clean as needed
- Perform combustion analysis (O2, CO, CO2, stack temperature)
- Test low-water cutoff and flame safeguard controls
- Test and inspect relief valve (replace if it weeps or is past its service life)
- Check expansion tank pressure and system fill pressure
- Inspect circulator pumps, couplings, and seals
- For steam: check water level, gauge glass, traps, and condensate return
- For condensing boilers: clean condensate trap and verify neutralizer
- Check water chemistry/treatment for larger systems
Boilers in Illinois are also subject to state inspection requirements. Keep your inspection certificate current and posted; we can help schedule repairs identified during an inspection.
Make-Up Air Units
- Test burner operation and modulation
- Verify interlock with exhaust fans or kitchen hoods
- Check filters, belts, and dampers
- Confirm discharge temperature setpoint
Controls and Building Automation
- Change schedules from cooling to heating; verify occupied/unoccupied setpoints
- Calibrate or replace faulty space sensors
- Confirm freeze protection on coils and outdoor air dampers
- Verify alarms go to the right people after hours
Typical Costs for Commercial Heating Startup
| Equipment | Typical Startup/Inspection Cost (per unit) |
|---|---|
| Gas unit heater | $150–$300 |
| RTU with gas heat | $200–$450 |
| Make-up air unit | $300–$600 |
| Commercial boiler (hot water) | $450–$1,200 |
| Steam boiler | $600–$1,500 |
Multi-unit sites get volume pricing, and costs are lower under a preventive maintenance agreement. Repairs found during startup are quoted separately.
Repair or Replace? Red Flags to Watch
| Finding | What It Usually Means |
|---|---|
| Cracked heat exchanger (RTU or unit heater) | Unit must be shut down; often replace if older than 15 years |
| Boiler section leaks | Major repair or replacement planning |
| Frequent flame safeguard lockouts | Combustion or control issue; may indicate end of life |
| High CO in combustion test | Immediate correction needed |
| Obsolete controls with no parts available | Plan upgrade before winter failure |
Des Plaines & Mount Prospect Buildings We Service
Our commercial clients include light-industrial buildings near the O’Hare corridor, strip retail on Rand and Northwest Highway, office buildings, and older multi-unit residential buildings with boilers. Many of these properties have a mix of equipment ages, and a startup visit gives owners a clear list: what’s fine, what needs repair now, and what to budget for next year. Learn more about our commercial HVAC services.
Financing Options
For smaller commercial owners, equipment replacements identified during startup can be financed through Sunbit and PowerPay.
Don’t Forget Carbon Monoxide and Venting
Every fuel-burning appliance in a commercial building needs a clear, properly sized vent path. During startup we look for disconnected or corroded flue pipe, bird and wasp nests in terminations, roofing work that has blocked or shortened vents, and backdrafting in mechanical rooms where exhaust fans compete with combustion air. In older multi-unit buildings, a boiler room with a sealed-up combustion air opening is a surprisingly common find. These issues rarely show up as a comfort complaint until someone gets sick, so they deserve a close look every fall.
Document Everything
A good startup visit should leave you with a written report for each piece of equipment: what was checked, combustion readings, deficiencies found, and recommended repairs ranked by urgency. That record helps with insurance, boiler inspections, warranty claims, and capital planning. It also makes it easy to compare year over year and spot units that are trending toward failure.
Tenant Communication Tips
For multi-tenant buildings, let tenants know when startup work is happening, especially if heat will be briefly off or technicians need access to suites for thermostats or unit heaters. Ask tenants to report cold spots, odd smells, or noisy equipment early in the season. Small complaints in October are much easier to solve than emergency calls in January, and good communication reduces frustration if a part has to be ordered.
Plan Replacements Before Peak Season
If your startup identifies equipment at the end of its life, the fall is the best time to plan. Contractors and suppliers are less stretched than in mid-winter, rooftop crane lifts are easier to schedule, and you can choose equipment deliberately instead of taking whatever is in stock during an emergency.
Frequently Asked Questions
When should I schedule commercial heating startup?
Late September through October, before sustained cold weather arrives.
Do I need a startup if the equipment is new?
Yes. Newer equipment still needs safety checks and filter changes, and many warranties require documented maintenance.
Can you work around business hours?
Yes. We schedule early morning, evening, or weekend service when needed.
What about CO detectors in commercial buildings?
Requirements depend on occupancy type and fuel-burning equipment. We can check coverage during startup and recommend placement.
Do you service residential multi-unit boilers?
Yes. We service boilers for condo associations, two-flats, and apartment buildings.
Book Your Heating Startup
MMDS serves commercial properties in Des Plaines, Mount Prospect, and throughout the northwest suburbs. Call (847) 221-6280 or contact us online to schedule before the first cold snap.