Tankless Water Heater Installation in Fort Collins and Loveland

How altitude changes a gas tankless water heater

The fuel gas code requires gas flow to be adjusted above 2,000 feet (IFGC 402.2), and every town we serve is above 4,600 feet (USGS).

Rinnai’s V-series units set altitude on DIP switches in bands, and Rinnai’s venting instructions show one 199,000 Btu/h natural gas model derating automatically:

Rinnai band	Input of the 199,000 Btu/h model	Drop	Towns at their USGS points
2,001-5,200 ft	170,000 Btu/h	about 15%	Fort Collins (5,004 ft), Loveland (4,986 ft), Windsor, Greeley, Longmont, Berthoud, Timnath, Johnstown, Severance, Milliken, LaPorte, Bellvue
5,201-7,700 ft	153,000 Btu/h	about 23%	Wellington (5,207 ft), Masonville, Livermore, Estes Park (7,530 ft)
7,701-10,200 ft	139,000 Btu/h	about 30%	Homes above 7,700 ft

Navien sets the NPE-2’s altitude in a menu, and its natural gas units need a high-altitude conversion kit (a gas orifice packed inside the case) at 5,400 feet or higher: Livermore and Estes Park, not Fort Collins or Loveland. Rinnai warns that wrong DIP switch settings can cause unsafe operation, damage and a voided warranty.

Settings follow your home’s own elevation, so we check homes near a band edge, such as Wellington, Masonville and Estes Park, on site.

Gas line, venting and power for a tankless water heater

Gas line and meter capacity

A whole-house gas tankless unit can burn several times the gas of a tank: one Bradford White spec sheet rates its 50-gallon atmospheric tanks at 34,000 to 50,000 Btu/h, against 199,000 for the Rinnai. The fuel gas code sizes piping for the sum of every connected appliance’s maximum input (IFGC 402.2), and Navien’s manual says the gas meter’s capacity must cover that total.

This Old House’s tankless cost guide (updated June 12, 2026) says some older homes need the line upsized from 1/2 inch to 3/4 inch, adding $400-$800. A meter upgrade typically goes through your gas utility. Loveland’s water heater permit asks for the old and new Btu input.

Condensing vs non-condensing tankless: venting and condensate

A condensing unit adds a secondary heat exchanger that pulls extra heat from the exhaust until its moisture condenses; ENERGY STAR says that cuts energy use 9% against a conventional gas tankless unit.

	Condensing	Non-condensing
Heat exchangers	Primary and secondary	Primary only
Exhaust vent	PVC, CPVC or polypropylene, per the manual	Hotter exhaust; the vent its listing names
Condensate	Acidic; drains, sometimes through a neutralizer	Designed not to condense
ENERGY STAR	Can qualify (UEF 0.95 or higher)	Not certified

Colorado’s fuel gas code requires new plastic exhaust pipe to pass a 5 psi air test at inspection, before it is connected. Loveland requires an exhaust test certificate and bans cellular-core pipe on direct-vent exhaust, even existing pipe; Windsor bans cellular-core PVC water heater vents. Vent terminals must sit at least 22 inches above grade in Fort Collins and Larimer County, and 12 inches above the expected snow level in Larimer County.

Navien puts its NPE-2’s condensate at pH 3 to 5 and lets it run to a drain directly or through a neutralizer. If your old tank shared a vent with a furnace, we confirm the furnace still vents properly alone. See water heater venting types.

Electrical needs

Many gas tankless units need only a 120-volt outlet; Navien’s NPE-2 plugs in and draws 2 to 4 amps. Electric whole-house units are a bigger job: This Old House’s June 2026 guide says most need 120-160 amps of dedicated service and multiple 240-volt circuits, and puts a full panel upgrade at $1,000-$2,000.

Whole-house vs point-of-use tankless water heaters

A whole-house unit serves every fixture from one spot. A point-of-use unit is a smaller heater, often electric, near one fixture or area; DOE lists remote bathrooms, hot tubs and dishwasher or clothes washer boosters. DOE also suggests two or more units where simultaneous uses outrun one, though they cost more.

What a complete written tankless quote includes

Every quote we write spells out:

• Make and model, Btu/h input, UEF, and gpm at your winter rise and altitude
• Condensing or non-condensing, with vent material, route and termination
• Labor, permit and inspection
• Gas line sizing, shutoff, flexible connector and sediment trap
• Vent pressure test and plans for the old vent
• Condensate drain and any neutralizer
• A 120-volt outlet, or circuits for an electric unit
• Isolation valves, relief valve, and expansion control if your system is closed
• Altitude setup: DIP switches, menu setting or kit
• How a gas model meets Colorado’s NOx rule
• Haul-away and any other code upgrades

Licensed plumbers covered by liability insurance do every job.

Water quality and tankless descaling

Rinnai’s V-series tech sheet says hard water must be treated to prevent scale build-up or damage to the heat exchanger, and repeated scale codes eventually lock the heater out. Navien’s NPE-2 manual requires a softener or Navien’s PeakFlow system above 12 grains per gallon and excludes damage caused by poor water quality from its warranty.

Most homes here start well under those limits. Loveland Water and Power’s 2025 report averages 24 mg/L of hardness (about 1.4 grains per gallon), Longmont reports about 22 mg/L and Estes Park 14 mg/L, and Fort Collins Utilities calls its water naturally soft. Scale still builds slowly over years, and private wells can test very differently, so compare your water quality report, or a test, with your model’s manual. We fit isolation valves so the unit can be flushed; see how to descale a tankless water heater or our tankless water heater repair service.

Rinnai, Navien, Noritz, Rheem and Takagi tankless installation

We install the common tankless brands, including Rinnai, Navien, Noritz, Rheem and Takagi, and your quote names the exact model. Altitude setup varies by maker: Takagi’s CT-199 indoor model changes bands at 5,000 feet, right around Fort Collins’ elevation, and Rheem’s ThermaForce RTGH is rated to 10,100 feet on natural gas but 7,800 on propane.