Tankless Water Heater Installation, Repair, and Replacement
Full Nelson installs, repairs, and replaces tankless water heaters that heat water on demand as it flows through the unit. Tankless systems eliminate the standby energy loss of keeping a tank of water hot 24 hours a day and provide continuous hot water without running out.
How Tankless Water Heaters Work
A tankless water heater does not store heated water. When you open a hot water faucet, cold water flows through the unit and passes over a heat exchanger. Gas-fired tankless units use a high-powered burner to heat the exchanger. Electric tankless units use heating elements. The water exits the unit at the set temperature and flows directly to the fixture.
Because there is no tank to deplete, a tankless unit provides continuous hot water as long as the demand stays within the unit’s flow rate capacity. The unit activates when it senses flow and shuts off when the faucet closes, using no energy between uses.
Tankless Water Heater Installation
Tankless installation involves more than swapping out a tank unit. Gas tankless water heaters have higher BTU input than tank units and may require a larger gas line, a dedicated venting system, and a condensate drain. Electric tankless units may require electrical upgrades to supply adequate amperage. Full Nelson evaluates your home’s gas supply, electrical service, and plumbing configuration before recommending a specific unit. Installation considerations include:
- Gas line sizing
A gas tankless unit draws significantly more BTUs than a tank water heater. The gas line serving the unit must be sized to deliver adequate volume at the required pressure. Undersized gas lines cause the unit to underperform or fail to fire at full capacity.
- Venting
Gas tankless units require dedicated stainless steel or PVC venting (depending on whether the unit is non-condensing or condensing). They cannot share a vent with other gas appliances. The vent can run horizontally through a side wall, providing placement flexibility.
- Flow rate matching
Tankless units are rated in gallons per minute (GPM). A single shower uses roughly 2 to 2.5 GPM. Running two showers and a dishwasher simultaneously might demand 6+ GPM. The unit’s capacity must match the household’s peak simultaneous demand.
- Condensate drain
Condensing tankless units produce acidic condensate that must be drained. A drain line is run to a floor drain, utility sink, or condensate pump.
- Recirculation
Some tankless units support recirculation systems that keep hot water available at the fixtures without a long wait. Full Nelson installs recirculation pumps and dedicated return lines for homes where hot water delivery speed is a priority.
Tankless Water Heater Repair
Tankless units are more complex than tank water heaters and contain circuit boards, flow sensors, gas valves, and heat exchangers that require specific diagnostic knowledge.
Common tankless water heater problems include:
- Error codes displayed on the unit's control panel indicating ignition failure, flame loss, exhaust blockage, or sensor faults
- Scale buildup inside the heat exchanger from hard water, reducing flow rate and heating efficiency. Descaling with a vinegar flush restores performance.
- Flame sensor or ignition failure preventing the unit from firing
- Flow sensor malfunction causing the unit to not activate or to cycle on and off erratically
- Condensate drain blockage on condensing units
Full Nelson recommends annual descaling for tankless water heaters in areas with hard water. Scale accumulation is the most common cause of tankless performance problems and the most preventable.
Tankless Water Heater Replacement
Tankless water heaters typically last 15 to 20 years with proper maintenance, longer than tank units. When the heat exchanger fails or develops internal leaks, replacement is usually more cost-effective than repair. Full Nelson removes the old unit, evaluates whether the existing gas line, venting, and electrical connections are adequate for the replacement unit, and installs the new system.
Why Full Nelson
- Family, Women, and Veteran owned since 2003
- Licensed, insured plumbers
- Gas and electric tankless installation
- Annual descaling and maintenance service
- Gas line sizing and venting modifications
- Up-front pricing before work begins
- 24/7 emergency service