Gig Harbor Heat Pump Installation | Coleman Inverter Add-On in 98335

The Challenge

This Gig Harbor homeowner had a gas furnace tucked into a crawl space but no cooling system. Adding a heat pump to that setup was the right long-term move: one system for both heating and cooling, inverter-driven efficiency, and the flexibility to lean on gas heat when winter temperatures drop. The homeowner met with Pacific twice before moving forward, working through the details of what a crawl space installation with ductwork modifications would actually involve.

The job required more than dropping in new equipment. The existing furnace was installed in an upflow orientation, which meant air moved straight up through the cabinet. To accept the evaporator coil that a heat pump system requires, the furnace had to be converted to a horizontal orientation so the coil could be positioned properly in the air stream. The existing ductwork also needed to be updated to handle both heating and cooling distribution effectively.

What the installation needed to address:

• No existing cooling system of any kind
• Furnace orientation conversion from upflow to horizontal in a crawl space
• Trunk line replacement and new flex duct run for proper cooling airflow
• New dedicated electrical circuit run from the main panel
• Crawl space lighting and outlet installed for future service access
• Condensate drainage from the new indoor coil
• Thermostat upgrade to support heat pump operation with outdoor temperature sensing
• All permits, inspections, and code compliance handled by Pacific

Our Solution

Pacific’s installation crew converted the crawl space furnace to horizontal operation and installed a 5-ton cased evaporator coil in line with the repositioned air handler. The outdoor unit, a Coleman HH860E2S11 inverter-driven heat pump, was installed outside and connected through the crawl with a 50-foot line set running both liquid and suction lines.

The ductwork was rebuilt where it needed to be. The existing trunk line was replaced, a new flex run was added, duct sealant was applied throughout, and a new Aprilaire MERV 11 filter was installed at the equipment. A new 60-amp dedicated electrical circuit was run from the main panel with a weatherproof disconnect outside, and new lighting and an outlet were added in the crawl space to give future service technicians safe working conditions.

The thermostat required a field adjustment during the job. With only five wires at the furnace, the originally specified thermostat was swapped for a Honeywell Prestige IAQ system with a wireless outdoor sensor, which gives the inverter heat pump the outdoor temperature data it uses to optimize efficiency. An air scrubber was also installed at the indoor unit to reduce airborne particulates circulating through the home.

Pacific’s sales advisor Keegan Peterson had visited twice before the installation, once to complete a full engineering assessment and once to walk through the ductwork modification scope, so the crew arrived on day one with the full plan already confirmed.

Equipment List

• Heat Pump: Coleman HH860E2S11, inverter-driven variable-speed, 4-5 ton, 18.0 SEER2, 9.0 HSPF2, R-454B refrigerant, ECM motor
• Evaporator Coil: Aspen DE61C4J-210L-535, 5-ton cased coil, R-454B, upflow/downflow/horizontal convertible, 21″W x 35″H
• Thermostat: Honeywell Prestige IAQ, with Redlink Internet Gateway and wireless outdoor temperature sensor for full heat pump control
• Air Scrubber: Non-ozone air scrubber mounted at the indoor unit, reduces airborne contaminants and surface pollutants
• Filtration: Aprilaire 16x25x4 MERV 11 filter media for improved particulate capture
• Ductwork: Trunk line replacement, new R-8 flex run, duct sealant throughout, 10-inch supply components
• Electrical: New 60-amp dedicated circuit from main panel, weatherproof GFCI disconnect, crawl space lighting and outlet
• Line Set: 3/8″ liquid line, 7/8″ suction line, 50-foot run through crawl space
• Condensate: Condensate pump, 20-foot lift, 120V for proper drainage from the indoor coil

Performance and Comfort Benefits

• Full heating and cooling from a single system, with the existing gas furnace available as a backup heat source during cold snaps
• Inverter-driven compressor modulates output continuously rather than cycling on and off, delivering steadier temperatures and quieter operation
• 18.0 SEER2 efficiency rating reduces cooling season energy use compared to standard single-stage equipment
• Rebuilt ductwork means cooled and heated air reaches every room without losing capacity to leaks or undersized distribution
• Crawl space lighting and outlet added during installation so future maintenance visits are safer and faster
• Prestige thermostat with outdoor sensor gives the inverter system the real-time data it needs to optimize performance at every outdoor temperature
• Air scrubber continuously reduces airborne particulates, allergens, and surface contaminants throughout the home
• $1,500 instant rebate applied for inverter equipment purchase, reducing overall project cost

Why This Matters for Gig Harbor Homeowners

A large share of homes in Gig Harbor were built with crawl space foundations, and many have gas furnaces tucked into that space with no cooling added during original construction. The mild reputation of Puget Sound summers has historically made cooling feel optional, but that has shifted. Warmer summers and longer heat windows have pushed more Gig Harbor homeowners to look at adding a heat pump to what they already have rather than replacing the entire heating system.

The crawl space location is the variable that changes the scope of these projects. When a furnace is oriented upflow in a tight crawl space, adding an evaporator coil is not as simple as slipping one in. The air handler has to be repositioned so the coil sits correctly in the airstream, and the ductwork often needs to be updated at the same time because systems built for heating alone are not always sized or routed to move cooled air efficiently through every room. Pacific’s advisors work through these details before the installation crew arrives, so there are no surprises when the job begins.

What this project also shows is why a thorough pre-installation assessment matters. Kevin Day’s job required two advisor visits to work through the furnace conversion scope and confirm the ductwork plan. That planning is what allowed a full crawl space heat pump installation, including duct rebuilding, electrical, and air quality upgrades, to be completed in two days without changes to the agreed scope. That is the standard Pacific holds every installation to, whether the job is straightforward or technically complex.