Water Heater Guide
Choose the right water heater for your Denver home. Compare tank, tankless, and heat pump options with altitude and efficiency considerations.
Water Heater Types
Conventional Tank (Gas)
Traditional storage tank heated by gas burner. Most common in Denver homes.
Advantages
- Lower upfront cost
- Simple technology
- Works well at altitude
- Easy installation
- No power needed for hot water
Disadvantages
- Standby heat loss
- Limited hot water supply
- Larger footprint
- Shorter lifespan
Conventional Tank (Electric)
Storage tank with electric heating elements.
Advantages
- Lower upfront cost
- No venting needed
- Safer (no combustion)
- Long lifespan
Disadvantages
- Higher operating cost
- Standby heat loss
- Slower recovery
- Needs 240V circuit
Tankless (Gas)
Heats water on-demand as it flows through the unit. No storage tank.
Advantages
- Endless hot water
- Energy efficient
- Long lifespan
- Compact size
- No standby loss
Disadvantages
- High upfront cost
- Altitude derating
- May need gas line upgrade
- Cold water sandwich effect
Tankless (Electric)
Electric on-demand water heating. Best for point-of-use applications.
Advantages
- Compact
- No venting
- Long lifespan
- High efficiency
Disadvantages
- Limited flow rate
- High electrical demand
- May need panel upgrade
- Struggles in cold climates
Heat Pump (Hybrid)
Uses heat pump technology to extract heat from air. Most efficient option.
Advantages
- Most efficient
- Lowest operating cost
- Tax credits available
- Cools surrounding space
Disadvantages
- High upfront cost
- Needs warm air space
- Slower recovery
- Noisy operation
Solar Water Heater
Uses solar collectors to heat water. Requires backup system.
Advantages
- Very low operating cost
- Eco-friendly
- Tax credits available
- Denver has great sun
Disadvantages
- Very high upfront cost
- Needs backup system
- Complex installation
- Roof space needed
Denver Considerations
Altitude Derating
Gas appliances lose 4% efficiency per 1,000 feet. At 5,280 feet, expect ~20% derating on tankless units.
Cold Inlet Water
Denver's cold groundwater (45-55°F) requires more heating. Affects tankless sizing significantly.
Hard Water
Denver has moderately hard water. Annual flushing recommended; consider water softener for tankless.
Energy Costs
Natural gas is relatively affordable in Denver, making gas units cost-effective despite lower efficiency.
Rebates
Xcel Energy offers rebates for high-efficiency water heaters and heat pump models.
Sizing Guide
| Household Size | Tank Water Heater | Tankless (GPM needed) |
|---|---|---|
| 1-2 people | 30-40 gallons | 3-4 GPM |
| 2-3 people | 40-50 gallons | 5-6 GPM |
| 3-4 people | 50-60 gallons | 6-8 GPM |
| 4-5 people | 60-80 gallons | 8-10 GPM |
| 5+ people | 80+ gallons or multiple | 10+ GPM or multiple |
Maintenance Tips
- Flush tank annually to remove sediment buildup
- Test temperature-pressure relief valve yearly
- Check anode rod every 2-3 years (replace if corroded)
- Insulate hot water pipes for efficiency
- Set temperature to 120°F for safety and efficiency
- Check for leaks around connections and tank base
- Clear area around unit for ventilation (gas units)
- Descale tankless units annually (especially with hard water)
Signs It's Time to Replace
- Unit is over 10-12 years old (tank) or 20 years (tankless)
- Rusty or discolored hot water
- Rumbling or popping noises from tank
- Water pooling around base of unit
- Inconsistent water temperature
- Frequent pilot light issues (gas)
- Significant increase in energy bills
- Visible rust or corrosion on tank
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