HVAC Guide: Northridge

Northridge housing at a glance

The HRCA history page dates the start of construction to 1980 and the first residents to 1981, with Northridge Park, the Northridge Recreation Center and Northridge Elementary all opening in 1982. Homes.com's neighborhood guide puts the median year built at 1991 and describes mostly multi-story single-family homes on cul-de-sacs, in new traditional, contemporary and Craftsman-inspired styles, plus townhouses and condos.

Size figures from the same guide help with equipment sizing: single-family homes average about 2,803 square feet on median lots of roughly 7,840 square feet, townhouses about 1,992 square feet, and two-bedroom units around 1,166 square feet. Those are the largest typical lots of the four original Highlands Ranch villages, which can give more freedom on where an outdoor unit goes.

Equipment age: most original systems are long gone

A furnace installed in 1985 has almost certainly been replaced at least once, and a 1990s house may be on its second system now. The useful question in Northridge is not whether the equipment is original but what was installed during the last swap, and whether the venting and ductwork were updated with it. An undocumented replacement from the early 2000s is now well over 20 years old.

Look at the furnace exhaust. A metal flue running up through the house usually means an 80%-efficiency, non-condensing furnace, often sharing that flue with the gas water heater. Two white PVC pipes leaving through a side wall or roof point to a 90%-plus condensing furnace. If you move from the first type to the second, the water heater can be left alone on a vent sized for two appliances, a situation called an orphaned water heater. The vent may then be too large to draft properly, so it often needs a liner or resizing as part of the job. Ask about it when you get furnace replacement quotes.

Colorado's furnace emissions law, in force since January 2026, allows only gas furnaces rated at or below 14 ng/J of NOx or certified to the latest ENERGY STAR version. That law, combined with altitude derating of about 4% per 1,000 feet, means a like-for-like replacement of a 1990s furnace is less automatic than it once was.

Swamp coolers, central air, and the ducts in between

Some early Highlands Ranch houses were built without central air or relied on an evaporative cooler. The HRCA guidelines treat both seriously: under section 2.5, the ARC must sign off on central air equipment and on evaporative coolers alike, looking at location and screening. Replacing a roof-mounted swamp cooler with a ground-level condenser also needs approval, and the old roof penetration has to be sealed properly.

Ducts in a 40-year-old two-story house are worth a look before adding or upsizing cooling. Ductwork sized for heating alone may move too little air for a new air conditioner, which shows up as a noisy return, a hot upstairs and a coil that freezes. A technician can measure static pressure to tell you whether the ducts or the equipment is the bottleneck. See our AC installation page for how we approach sizing.

HRCA rules for outdoor equipment in Northridge

Northridge falls under the Highlands Ranch Community Association's Residential Improvement Guidelines, October 2024 edition. Ground-level condensers and heat pumps are reviewed for screening, placement and proximity to the neighbor's living areas, and nothing can sit above street level unless it is fully concealed. Exterior pipes, conduits and equipment need approval too, and must be screened or painted to match the house, which is how line sets for a new heat pump or mini-split are judged.

Approval timing matters if your AC dies in July. A same-location replacement is usually simple to get approved, but relocating the pad, adding a second unit, or mounting mini-split heads on an upper wall should go in front of the ARC first. HRCA Community Improvement Services is at (303) 471-8821.

Heat pumps in older Northridge homes

Northridge homes are on Xcel Energy for gas and electricity, and the Highlands Ranch heating design temperature is about 4°F, so a cold-climate heat pump can carry most of the season with a gas furnace backing it up. Older houses sometimes need an electrical panel review first, since a heat pump adds a 240-volt circuit and some 1980s panels have little spare capacity.

Current incentives: Colorado's air-source heat pump credit is worth $1,000, and the registered contractor who claims it has to take at least $333 off the homeowner's invoice; Power Ahead Colorado's rebate is $1,500 for an eligible cold-climate unit, provided the contractor reserves it before installation. The federal 25C credit no longer applies to equipment placed in service after 2025, and Xcel's own rebate amounts changed on October 1, 2026, so check them directly. Our heat pump vs. furnace guide compares running costs.

Permits come from the Douglas County Building Division, which handles furnace and AC replacements as online basic mechanical permits. A permitted gas appliance replacement also triggers Colorado's CO alarm requirement near every sleeping area.

Northridge HVAC Questions

When were Northridge homes in Highlands Ranch built?

Construction began in 1980 and the first families moved in during 1981. Homes.com puts the neighborhood's median year built at 1991, so there is a mix of early-1980s houses and homes from the late 1980s through 2000s.

Will a new high-efficiency furnace affect my water heater?

It can. If your current furnace shares a metal flue with a gas water heater, switching to a condensing furnace with PVC venting can leave the water heater alone on an oversized flue. The vent often needs a liner or resizing, which should be in the quote.

Can I replace a swamp cooler with central air in Northridge?

Yes, with HRCA approval. Section 2.5 of the HRCA guidelines covers both evaporative coolers and air conditioning equipment, so the new condenser location and the removal of the cooler should be submitted before work starts.

Is my Northridge house too old for a heat pump?

Age alone is not the issue. Duct capacity, insulation and electrical panel space matter more, and a dual-fuel setup that keeps the furnace is common in older homes. Call (720) 466-7983 for an assessment.