1797 Park Drive, Traverse City, MI 49686
Phone: 866-BOB-HEAT

5 Boiler Warning Signs to Watch For

5 Boiler Warning Signs to Watch ForHow will you know when your home’s boiler system needs attention? Here are five signs to watch for and what you should do about each:


Check your boiler’s age. A unit more than 15 years old is likely much more inefficient than today’s models, and likely will begin showing signs of failure such as rusting and leaks. Annual Fuel Utilization Efficiency (AFUE) ratings allow you to compare and contrast new systems (higher ratings mean lower energy costs). New boilers can be smaller than old models they replace, while delivering the same amount of heat, saving you money. A professional HVAC contractor will calculate exact sizing needs to help you.


Natural gas is odorless; utilities add mercaptan, a foul-smelling chemical to make leaks noticeable. Fuel oil has a sharp odor you should learn to recognize. Any unusual smell needs professional investigation. A gas leak is an immediate emergency. A fuel oil leak wastes money but can also lead to chronic health problems. Cat litter absorbs small oil leaks.

You have no chance of smelling carbon monoxide (CO), an odorless poisonous gas that comes from incomplete burning of fuel (gas or oil). Install CO detectors to do the sniffing for you.


A boiler can leak water, hydronic fluid or oil. Look on the floor around your boiler:

  • Rust-colored puddles from water
  • Dark oily patches from fuel oil
  • Spatter marks from pressurized hydronic fluid spray

All of these leaks need professional attention but may need a repair as minor as a burner nozzle replacement or tightening a pipe joint.


Inconsistent heat is a sign your unit is fighting to overcome inefficiencies from several possible sources:

  • clogged burner
  • cracked heat exchanger
  • faulty thermostat

Your professional HVAC contractor should inspect and repair the system.


Boilers are generally quiet. If yours makes hissing, thumping or banging sounds, you may have sludge deposits within the boiler, your heat exchanger may be corroded, or you may hear kettling due to scale (lime deposits). All of these issues need professional cleaning and service.

For help evaluating the efficiency of your Northern Michigan home’s boiler, please contact us at Team Bob’s Heating Cooling Plumbing.

Our goal is to help educate our customers in Traverse City, Michigan and surrounding areas about energy and home comfort issues (specific to HVAC systems).  For more information about boilers and other HVAC topics, download our free Home Comfort Resource guide.

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Thank you for considering Team Bob’s for your heating, cooling, and plumbing needs! If you need immediate assistance, please call our 24/7 emergency hotline at 866-BOB-HEAT. Otherwise, please select a date and time below to request an appointment.

Please note: Your requested appointment date and time is not guaranteed. A member from our team will contact you by the following business day to confirm your appointment date and time.