No hot water forces a decision, and the right answer depends on the age of the unit, what has failed, and what a repair would cost against a replacement. This guide gives you the decision framework. It does not give prices: those depend on the unit, the install and the code corrections, and they are quoted per job.
How old is it?
A tank water heater typically lasts 8-12 years, and a tankless unit longer with maintenance. If the tank is over 10 years old and the repair is a major component, replacement is usually the better use of money. If the unit is under 6 years old and the fault is a thermostat, igniter or thermocouple, a repair usually makes sense. Check the rating plate for the manufacture date.
What has failed?
Component failures can be repaired
Some failures are repairs: a failed thermostat, a pilot that will not stay lit, a leaking drain valve, or a faulty heating element. Some failures are replacements: a leaking tank. A tank that leaks from the bottom is corroded from the inside, and no repair fixes that. See why your water heater is leaking from the bottom.
Denver factors
Hard water, cold inlet water, altitude
Denver's water is soft to moderately hard, with annual-report averages of about 89-105 mg/L, and scale shortens tank life and is the main tankless risk. January inlet water is cited at 43°F, which matters for tankless sizing and for recovery time on a tank. Gas units at 5,280 feet need high-altitude configuration. And a replacement in Denver needs a permit and inspection, with an expansion tank on a closed system and code corrections where the existing install does not meet code.
Water heater repair or replacement checklist
- Age: under 6 years favours repair; over 10 years favours replacement.
- Failure: component failure favours repair; a leaking tank means replacement.
- History: repeated repairs in a short period favour replacement.
- Efficiency: a new unit is more efficient than a 15-year-old one, but the saving depends on your use.
- Code: a replacement brings the install up to the code in force at permit time, including expansion tank and venting.
If you are not sure, a diagnosis visit settles it: the unit's age, the failure and the condition of the tank are all visible on site. See water heater repair, water heater installation and tankless water heater installation. Call (720) 599-7253 to arrange a visit.