Heat Pump and Oil Conversion Projects in Shoreline and Lake Forest Park, WA

Shoreline and Lake Forest Park sit just outside Seattle but inside Seattle City Light’s service area, and that in-between position shapes every heat pump decision here: you get City Light electricity at a slightly higher suburban rate, but not the City of Seattle’s oil conversion rebate or its permit office. The Seattle Heat Pump Company plans ducted heat pump installations and oil conversions across Richmond Beach, Echo Lake, North City, Ridgecrest and Lake Forest Park, and licensed and insured contractors carry out the work.

Heating oil is more common here than in most of the region. Census estimates put about 4.1% of Shoreline households and 6.5% of Lake Forest Park households on oil, higher than Seattle’s citywide 2.9%. Those homes face a conversion without Seattle’s city-funded help, so knowing what does and does not apply comes first.

What changes at the city line

Seattle Clean Heat’s $2,000 rebate, its $4,000 moderate-income bonus and the Office of Housing’s free conversions for income-eligible households are City of Seattle programs for homes inside city limits. A Shoreline or Lake Forest Park address does not qualify, even with a City Light account.

Several things do carry across the line:

• City Light’s contractor discount of $300 (SEER2 15.2 and HSPF2 8.1, retrofits) or $600 (SEER2 16.0 and HSPF2 9.5) follows the City Light account, one system per home, through participating distributors and contractors. Ask that it appear on the invoice.
• PLIA’s Heating Oil Loan and Grant program is a state program, not income-limited, offering up to $75,000 per project. PLIA must approve the work before it starts; decommissioning a tank first forfeits the funding. PLIA takes applications in a limited window each year, usually in late fall, so check PLIA’s site for the current dates.
• PSE’s income-qualified gas-to-heat-pump rebate of $4,000 requires PSE gas service but not PSE electric, so gas-heated households here may qualify; confirm with PSE, and note PSE requires a Trade Ally installer since April 2, 2026.

PSE’s hybrid rebate does not apply, because it requires PSE electric service, and neither does its electric-resistance conversion rebate. The federal 25C tax credit ended for equipment placed in service after December 31, 2025. The rebate guide covers City Light’s terms in detail.

Converting from oil without the city rebate

The engineering of an oil to heat pump conversion is the same on either side of NE 145th Street. The oil furnace’s ducts usually carry over, an electric air handler or a heat pump coil replaces the burner, and a new outdoor unit goes on a pad or bracket. What differs is the paperwork and the budget.

Without Seattle Clean Heat, the City Light discount and any PLIA loan become the main offsets, so sequence matters. If PLIA funding is part of the plan, the application goes in and gets approved before any tank work begins. If not, the heat pump goes in first and the tank is decommissioned after, so the house is never without heat.

Tank permits here come from the Shoreline Fire Department’s Fire Marshal’s Office, which issues residential tank decommissioning permits for Shoreline, Lake Forest Park and Kenmore. Its records begin in January 2004; for tanks handled before then, the city may hold the paperwork, which is worth checking before a sale. The work is done by an ICC-certified decommissioner, by removal or by cleaning and filling in place. Filling a clean tank in place typically runs about $700 to $3,000 in the Seattle area before the fire permit. A tank suspected of leaking is a different job, priced only after inspection. Oil tank decommissioning explains the two methods, and the oil conversion cost guide shows how the heat pump and the tank are budgeted separately.

Gas homes and the suburban rate

Gas is the larger group: about 44% of Shoreline households and 53% of Lake Forest Park households heat with it. City Light’s current suburban rate is 14.64 cents per kWh in Shoreline and 14.65 cents in Lake Forest Park, compared with 13.38 cents in Seattle. With PSE gas at about $1.67 a therm, a heat pump beats a 95% efficient gas furnace on energy cost once it averages a coefficient of performance of about 2.4. A modern unit clears that through most of a Puget Sound winter, so in most houses an all-electric furnace to heat pump conversion makes more sense than keeping gas as backup. The operating cost guide estimates the running cost on each rate.

The houses: postwar, with ducts more often than not

Shoreline’s largest building decade is the 1950s, about 23% of homes, followed by the 1960s at about 18%, by Census counts. Lake Forest Park has an older fringe, about 12% before 1940, but most of its housing, about 55%, went up between 1950 and 1979. Houses of those decades were commonly built around a forced-air furnace, which gives a ducted heat pump a working duct system to start from.

The ducts still need measuring. A heat pump delivers air cooler than a furnace and needs more of it, so a static pressure test checks whether the returns and trunks can carry the higher airflow. Split-levels and houses with added rooms often have one end that never quite warms up, and that is usually a duct problem rather than an equipment one. Using a heat pump with existing ductwork covers how those readings lead to fixes.

Sizing comes from a room-by-room load calculation for the local design day. Shoreline does not appear in Seattle’s energy code climate table, but its neighbors on both sides do: Seattle and Edmonds are both listed at 24°F for heating. Backup heat is set to stay off in mild weather so it acts as a safety net, and commissioning verifies airflow, charge, defrost and controls before handover.

Two permit offices, not one

In Seattle, SDCI issues both the trade and electrical permits. Here the mechanical permit comes from the City of Shoreline or the City of Lake Forest Park, and the electrical permit and inspection come from Washington Labor & Industries. A new circuit, a disconnect or a panel upgrade all go through L&I. A 100A to 200A upgrade typically adds about $1,333 to $4,500 in the Seattle area and houses that never carried an electric heating load are where the question most often comes up.

Outdoor unit siting follows each city’s own noise and setback rules, which the design checks for the specific lot. Richmond Beach and Innis Arden face Puget Sound, and bluff-top houses there take salt-carrying wind; manufacturers such as Mitsubishi Electric offer coated coils or seacoast packages on some units, and Carrier advises washing coastal units about every three months. The full process is on our ducted heat pump installation page. Just south of the line, Lake City and Northgate share the housing era but fall under Seattle’s programs.