Yes — boilers need annual maintenance, and skipping it shortens the system’s lifespan, reduces efficiency, and can allow safety problems to develop quietly. A well-maintained boiler in a Denver home can run reliably for 20 to 30 years. One that’s neglected tends to fail earlier, cost more to operate, and sometimes fails at the worst possible time — during a Colorado cold snap when you need it most.

What Happens During a Boiler Tune-Up

A proper boiler maintenance visit covers both the mechanical and safety sides of the system. A Done technician will inspect and clean the burner assembly, check the heat exchanger for cracks or corrosion, test the pressure relief valve, verify the expansion tank is functioning correctly, and inspect all venting for blockages or deterioration. We also test combustion efficiency — important at Denver’s altitude, where the reduced oxygen content at 5,280 feet affects the air-to-fuel ratio and can cause incomplete combustion if the system isn’t properly tuned.

We’ll also check the circulator pump, zone valves, aquastat settings, and controls. If the system uses glycol (common in radiant systems and some hydronic setups), we test the freeze protection level — especially important before Front Range winters where temperatures can drop well below zero.

Why Colorado Conditions Make Maintenance More Important

Denver’s hard water is one of the bigger long-term threats to a boiler. Mineral scale — primarily calcium and magnesium deposits from Colorado’s high-mineral water supply — builds up on heat exchanger surfaces over time. Even a thin layer of scale acts as an insulator, forcing the boiler to work harder to transfer heat into the water. This raises operating costs and accelerates wear on components. During a maintenance visit, we check for scale and advise on water treatment if buildup is progressing.

Venting is another area that deserves close attention in Colorado. Boilers with power vents or sealed combustion systems can be affected by debris, bird nests, or snow and ice accumulation around exterior terminations. A blocked vent can cause carbon monoxide to back-draft into the home — a genuine safety risk that annual inspection catches before it becomes dangerous.

Signs Your Boiler May Need Attention Between Annual Visits

  • Unusual noises — banging, kettling, or gurgling sounds often indicate scale buildup or air in the system
  • Uneven heating across zones or radiators that won’t get fully warm
  • Pressure gauge reading outside the normal range (typically 12–18 PSI when cold)
  • Pilot light or ignition issues on older systems
  • Visible rust, corrosion, or moisture around the boiler body or connections
  • Higher gas bills without a change in usage patterns

How Often Should You Schedule Service?

Once a year is the standard recommendation, and the best time is early fall — before the heating season starts — so any issues are caught before you actually need the system. If your boiler is older (15 years or more), or if it’s been more than two years since the last service, it’s worth scheduling sooner rather than later. An aging boiler that’s running but hasn’t been inspected may have developing issues that a technician can catch before they become an emergency.

Maintenance Plans and What They Cover

Done’s Care Club maintenance membership includes annual heating system tune-ups, priority scheduling, and discounts on repairs — so you’re not paying full price when something does need attention. For homeowners with boilers, this takes the annual service reminder off your plate entirely and keeps the system on a regular inspection schedule without having to remember to call.

To schedule boiler maintenance or learn more about our heating service options, visit our boiler repair and service page or explore our full heating services. Our Care Club membership is a good fit if you want annual tune-ups built into one plan.