Graham Heat Pump Installation Replaces Aging Electric Furnace in Manufactured Home

The Challenge

The homeowner was running a 21-year-old electric furnace in a closet-mounted configuration with no central air conditioning. Electric resistance heat is straightforward, but after two decades it runs hard, pulls more power than modern equipment, and leaves the home without any cooling on warmer days. The goal was clear: add efficient heating and cooling in one step, keep everything in the existing closet footprint, and qualify for every available rebate to bring the investment down.

• Replace the aging electric furnace before another Western Washington winter
• Add central air conditioning for the first time without running new ductwork
• Fit all new equipment inside the existing closet and use the existing duct system
• Apply the full Tacoma Power rebate for converting electric heat to a variable-speed heat pump
• Keep operating costs predictable with a system sized for the home

Our Solution

Pacific installed a matched Hisense inverter-driven heat pump system. The outdoor unit handles both heating and cooling. The new air handler slid into the existing closet in the same downflow orientation as the original furnace, which kept the project clean and preserved the ductwork. A 10 KW electric heat strip was integrated into the air handler to cover the coldest stretches, and the existing programmable thermostat was kept and rewired to the new system. Pacific pulled permits, handled the Pierce County mechanical and electrical inspections, and coordinated the $2,000 Tacoma Power instant rebate for converting electric heat to a variable-speed heat pump.

Equipment List

• Heat Pump: Hisense Hi-Ultra Side-Discharge Heat Pump (AOH-24U3T25U), 2-ton inverter-driven with up to 17 SEER2 and 8.5 HSPF2, rated for low-temp heating down to -13°F
• Air Handler: Hisense Matched Air Handler (AUH-2424), downflow configuration sized for the existing closet with factory-installed TXV
• Backup Heat: 10 KW integrated electric heat strip (WTM1002BX), 32,800 BTU for colder stretches
• Air Cleaner: Aprilaire MERV 11 4-inch Media Air Cleaner with 20×20 cabinet for stronger filtration and longer filter life
• Refrigerant: New refrigerant line set routed through the crawl space using R-454B low-GWP refrigerant
• Electrical: New 30-amp outdoor disconnect, GFCI-protected receptacle, and whip to current code

Performance and Comfort Benefits

• Central air conditioning added for the first time, with no new ductwork needed
• Inverter-driven operation ramps up and down smoothly instead of cycling on and off, which means steadier temperatures and quieter runs
• Heat pump efficiency on heating replaces straight electric resistance, which typically lowers winter electric bills on a home like this
• Low-temp heating to -13°F keeps the heat pump as the primary heat source through almost every Graham winter day
• Stronger 4-inch media filtration captures more dust and allergens than a standard 1-inch filter and lasts up to 12 months
• New equipment sits in the same closet as the old furnace, so no interior finish work was needed

Why This Matters for Graham Homeowners

Graham has a large number of manufactured and mobile homes built in the late 1990s and early 2000s, and many of those homes still run their original closet-mounted electric furnaces. Those furnaces were solid when they were new, but after 20 years they cost more to run, offer no cooling, and leave the home vulnerable when something finally fails in the middle of a cold snap or summer heat wave. Swapping to an inverter-driven heat pump is usually the strongest move available because it handles both heating and cooling from one outdoor unit and runs on a fraction of the electricity of straight resistance heat.

Rebates matter here. Graham homes served by Tacoma Public Utilities currently qualify for a $2,000 instant rebate when an electric furnace is replaced with a variable-speed heat pump, which is exactly what we applied on this project. Pacific handles the rebate paperwork, the heat load calculation, the balance point worksheet, and the AHRI certification required to claim it, so the homeowner does not have to chase any of it down. Learn more about local utility rebates here.

For manufactured homes specifically, the work is about precision. The new air handler has to fit the existing closet, sit in the same orientation as the original furnace, and tie into the existing duct system without creating airflow or condensate problems. On this job, we matched the downflow orientation, reused the existing ductwork, routed the refrigerant lines through the crawl space, and pulled permits with Pierce County so the mechanical and electrical work was inspected and signed off the same way we would on any site-built home.