A tankless water heater warms water only as it flows, so there is no tank to keep hot, and the Department of Energy says most last more than 20 years. The tradeoff is a limited flow rate and installation work on gas, venting or electrical service. Call the number on this page to be connected with a local plumber in Denver for an install, repair or descaling.

How on-demand heating works
When a hot tap opens, water passes through a heat exchanger warmed by a gas burner or electric elements. According to the Department of Energy, tankless units typically deliver 2 to 5 gallons of hot water per minute, and gas models produce higher flow rates than electric ones. That makes sizing the key decision: a unit has to keep up with the fixtures that run at the same time.
Is it a good fit for your house?
- Good fit: smaller households, homes short on utility space, owners planning to stay long enough for the longer life to pay off.
- Harder fit: families who run two showers and a dishwasher together, or homes where the gas line or electrical panel would need major upgrades.
Installation details that matter
Gas tankless units draw a lot of fuel at full fire and often need a larger gas line than the old tank used. They also need their own venting, which may run through a wall rather than the old flue. Whole-house electric models can require heavy dedicated circuits. In Denver, a water heater in a single-family or duplex home is a quick permit through Community Planning and Development.
Upkeep and Denver water
Mineral scale builds inside a heat exchanger over time, and most manufacturers call for periodic descaling. Denver Water describes its water as soft to moderately hard, with harder water in the southern system and in winter, so how often a unit needs flushing depends partly on where you live. Clean the inlet screen too. Some owners have a plumber install isolation valves at the unit during the original install, which makes later flushing quicker and simpler. If your unit lacks them, ask about adding a set at the next service visit.
Common repair calls
- Error codes for ignition or flame failure
- Water that turns cold mid-shower, often a flow or sizing issue
- Scale warnings or reduced output
- Venting or condensate drain problems on condensing models
What affects cost
The unit's capacity, gas versus electric, how much gas line, venting or electrical work the house needs, where the unit mounts, and the permit. A tankless swap usually costs more up front than a like-for-like tank. Ask for a quote that spells out each part of the work.
Tankless Water Heater questions from Denver homeowners
How long do tankless water heaters last?
Can a tankless heater run two showers at once?
How often should a tankless heater be descaled?
Do I need a permit for a tankless water heater in Denver?
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Helpful guides
Tankless Water Heaters in nearby cities and towns
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Weld County
Elbert County
Park County
Gilpin County
Clear Creek County
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