A tankless water heater delivers hot water on demand — heating it as it flows through the unit rather than storing 40 or 50 gallons in a tank that has to be kept hot around the clock. For Denver-area homeowners, that means meaningful energy savings, a unit that takes up a fraction of the space, and hot water that doesn't run out mid-shower. Getting that tankless heater from Done means it's sized correctly for your household, installed to code at Colorado's altitude, and backed by a team that will service it for the life of the unit — not just hand you a warranty card and walk away.

Sizing Matters More Than Most Homeowners Realize

The most common complaint about tankless water heaters — “it doesn't keep up when we're running two showers at once” — is almost always a sizing problem, not a product deficiency. Tankless units are rated by flow rate (gallons per minute) and by the temperature rise they can achieve at that flow. In Colorado, groundwater entering your home can be quite cold, especially in winter, which means the heater needs to raise water temperature by a larger margin than it would in a warmer climate. Done's plumbers calculate the right unit for your household's simultaneous fixture demand and your home's actual incoming water temperature — not just a generic “family of four” estimate that may leave you with a unit that struggles on cold mornings.

Altitude Calibration Is a Real Factor in Denver

Gas-fired tankless heaters need to be properly set up for Denver's ~5,280-foot elevation. At altitude, there's less oxygen in the air, which affects combustion efficiency and heat output. Manufacturers specify altitude adjustment procedures — sometimes involving dip switch settings, sometimes requiring a high-altitude orifice kit — and these steps are easy to skip or perform incorrectly if the installer isn't familiar with them. An improperly calibrated unit at altitude can produce error codes, inconsistent hot water, or reduced efficiency. Done's plumbers install tankless heaters regularly in the Denver metro and know exactly what the altitude setup requires for the brands and models we carry.

Hard Water Management for Tankless Units

Denver's hard water is the number-one enemy of a tankless water heater's heat exchanger. Mineral scale builds up inside the narrow channels of the exchanger and progressively reduces efficiency and flow — eventually causing the unit to overheat and shut down on error. Done will discuss your water hardness at installation and can recommend water treatment solutions if scale is a concern. We also offer tankless maintenance — annual descaling flushes that dissolve mineral buildup and keep the unit running at full efficiency. A tankless heater with annual maintenance in a hard-water area will outlive a neglected one by years.

Long-Term Savings and Energy Efficiency

Traditional tank water heaters keep 40–80 gallons of water hot 24 hours a day, even at 2 a.m. on a Tuesday when no one is home. That constant standby heat loss accounts for a meaningful portion of a home's energy bill. Tankless units eliminate standby loss entirely, heating water only when a tap is opened. For households with high hot water demand — or those who want to reduce their gas or electric utility costs — the long-term savings are real, and the longer you stay in your home, the more that payback compounds. Financing options are available through Done if the upfront cost is a consideration.

  • Endless hot water — no tank to drain, no cold-water sandwich between users
  • Properly sized for your household's simultaneous demand and Colorado's cold groundwater
  • Altitude-calibrated installation for Denver's ~5,280-foot elevation
  • Compact footprint — frees up closet or utility room space
  • Lower energy costs from eliminating standby heat loss
  • Done services what we install — annual descaling and full ongoing support

Done Services What We Install

One of the less-discussed advantages of buying from Done is continuity. We keep service records, we know what unit you have, and when you call for maintenance or a future repair, you're talking to a team that has history with your system. That's worth something over a 15–20-year appliance lifespan. Our Care Club membership makes scheduling annual descaling easy and ensures your tankless heater stays on a maintenance rhythm that maximizes its useful life.

Ready to explore going tankless? Visit our tankless water heater page for details on what we carry and install. You can also review financing options or learn about the Care Club maintenance membership that keeps your new heater running efficiently for years to come.