Frequently Asked Questions

Q: How do I know if my furnace needs repair or full replacement?

A: Systems over 15 years old with frequent repairs and rising energy bills usually warrant replacement. Shorter cycling, uneven heating, or cool air from vents often mean a repair can still solve the problem.

Q: What's the difference between gas, LP, and fuel oil heating systems?

A: Gas connects to a utility line with lower operating costs. LP is tank-stored and common in rural Michigan where gas lines don't reach. Fuel oil delivers strong heat but requires storage and deliveries. Justice Pro Mechanical services all three.

Q: When should I schedule heating maintenance before a Michigan winter?

A: September or October, before the first hard freeze. Pre-season tune-ups catch worn ignitors, cracked heat exchangers, and airflow issues before they leave you without heat on a subzero night.

Q: Why is my AC running but not actually cooling the house?

A: Usually a dirty filter restricting airflow, low refrigerant from a leak, or a failing compressor. If you see ice forming on the unit, shut it off immediately to prevent compressor damage and call for service.

Q: How long does a central AC unit typically last in Michigan?

A: Most units last 12–17 years with proper maintenance. Michigan's summer humidity works the system hard, and skipping annual service can cut lifespan by several years. Our $20/month preventive maintenance program helps avoid that.

Q: What size AC unit does my home actually need?

A: Sizing depends on square footage, insulation, window count, and sun exposure. An undersized unit runs nonstop without cooling; an oversized unit short-cycles and creates humidity problems. A proper load calculation prevents both.

Q: What's the difference between a steam boiler and a hot water boiler?

A: Steam boilers heat water into steam that rises through pipes without a pump. Hot water boilers circulate heated water with a pump for more even, efficient heat. Justice Pro Mechanical has experience with both types.

Q: Why is my boiler making banging or knocking noises?

A: Banging typically means mineral scale is trapping water in the heat exchanger, causing overheating. Knocking in steam systems indicates trapped condensate. Both worsen over time and should be diagnosed before causing cracks or leaks.

Q: How often does a boiler need to be flushed or serviced?

A: At least once a year, ideally before heating season. Flushing removes sediment that reduces efficiency and accelerates corrosion. Michigan's hard water speeds up scale buildup, making annual flushes especially important in the Adrian and Ann Arbor area.

Q: How does commercial HVAC maintenance differ from residential?
A: Commercial systems face heavier loads, longer run times, and more complex ductwork — requiring more frequent filter changes, belt inspections, and refrigerant checks. Justice Pro Mechanical offers a $20/month preventive maintenance program to minimize costly downtime.

Q: What are common signs a commercial rooftop HVAC unit is failing?

A: Hot and cold spots throughout the building, unusual odors from vents, excessive rooftop unit noise, and rising utility costs. Because rooftop units are out of sight, problems often go unnoticed longer — making routine inspections essential.

Q: Can a commercial refrigeration issue be handled by a regular HVAC technician?

A: Not always. Commercial refrigeration involves different refrigerants, compressor types, and temperature thresholds than comfort cooling. You need a technician trained specifically in refrigeration to avoid misdiagnosis or voiding warranties.