Water Heaters in Mercer Island, WA
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Water Heater Services in Mercer Island, WA
Fast Water Heater provides prompt, professional service for all your water heater needs in Mercer Island, Washington. Mercer Island is home to upscale single-family homes, waterfront properties, and modern condos — many with unique plumbing considerations. Whether you need a new installation, emergency repair, or energy-efficient upgrade, our licensed technicians are ready to help.
We pull permits through the Mercer Island Community Planning & Development Department and ensure every job meets all State and local requirments.
Brands we service and install:
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Water Heater Installation in Mercer Island
Whether you’re upgrading an aging tank unit or making the switch to a high-efficiency tankless or heat pump system, Fast Water Heater Company handles every installation to code. We work with Bradford White, Navien, Noritz, Rheem, and Rinnai — and pull all required permits through the Mercer Island Community Planning & Development Department.
Traditional gas and electric tank units (30–80 gallons) for single-family homes and condos. We size correctly for your household and ensure proper earthquake strapping per Mercer Island seismic codes.
On-demand hot water with no standby heat loss — ideal for Mercer Island’s high-value homes. Gas models qualify for PSE rebates up to $660 and Federal 25C credits.
The most efficient electric option — qualifies for PSE rebates up to $850, WA HEAR program up to $1,750, and a Federal tax credit up to $2,000. Great for Mercer Island homes with conditioned garage or utility spaces.
Natural gas installations with proper Type B venting, sediment traps, and gas shutoff. We replace obsolete greasepack valves and verify PRV settings per 2021 UPC requirements.
Reliable electric tank and hybrid systems for homes without gas service. All installations include drain pans, proper bonding (#6 AWG), and R-10 insulation for concrete floor placement.
We handle all permits through Mercer Island CPD. Every installation includes seismic straps, expansion tanks for closed systems, T&P relief valve piping, and inspection-ready documentation.
Local Codes & Compliance in Mercer Island
Mercer Island enforces the 2021 Uniform Plumbing Code (UPC), International Fuel Gas Code (IFGC), and International Residential Code (IRC) with Washington State amendments. These ensure safe, efficient water heater installations. Below are key requirements — always consult the Mercer Island Community Planning & Development Department for permits and inspections.
Required for all closed plumbing systems to prevent excessive pressure from thermal expansion on the water heater and pipes (2021 UPC).
Two ¾-inch x 22-gauge metal straps — upper and lower thirds of tank — mandatory in Mercer Island’s Seismic Design Categories D0–D2. ¼-inch lag screws into framing; plumber’s tape not acceptable.
Gas heaters prohibited in bedrooms/bathrooms unless direct-vent. In garages, ignition sources must be 18 inches above floor; FVIR units or steel bollard protection required in traffic paths.
Type B double-wall vent piping with 1-inch clearance to combustibles (6 inches at draft hood), secured with three screws per joint. Sediment traps (6-inch drip leg) required upstream of gas control valve.
¾-inch T&P valve required, piped 6–24 inches above grade. Pressure-reducing valve required if supply exceeds 80 PSI. Drain pan with connected drain line required for all indoor installations.
Gas and water piping bonded with #6 AWG copper (UPC §604.8). Dedicated full-port shutoff on cold-water inlet. Hot/cold pipes insulated R-3 minimum in unconditioned spaces; R-10 under electric units on concrete.
Water Heater Replacement in Mercer Island
We’ve replaced water heaters across Mercer Island’s varied housing stock — waterfront estates, island condos, and mid-century single-family homes. Background-checked, extensively trained technicians every time.
Most Mercer Island replacements happen the same day you call. Whether upgrading to tankless or swapping a failed tank unit, we respond fast to minimize disruption.
Replace your old tank with a heat pump water heater and qualify for PSE rebates up to $850, WA HEAR up to $1,750, and a Federal tax credit up to $2,000 (IRS Form 5695).
We provide an initial estimate over the phone and confirm the final price on-site after assessing your setup. No hidden fees, no obligation.
Every replacement includes updated seismic strapping, expansion tank (if closed system), T&P valve, drain pan, and all permits pulled through Mercer Island CPD.
We carry Bradford White, Navien, Noritz, Rheem, and Rinnai — matching the right unit to your Mercer Island home’s size, fuel type, and efficiency goals.
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Water Heater Repair in Mercer Island
Call by noon for same-day service. Our technicians serve Mercer Island 7 days a week, 7AM–7PM weekdays and 8AM–5PM weekends — with no extra weekend charges.
If your gas water heater won’t stay lit or fails to heat, we diagnose and replace faulty thermocouples and gas control valves — including upgrading obsolete greasepack valves to compliant ball valves.
Anode rod replacement prevents tank corrosion. We also flush sediment buildup that reduces efficiency and causes rumbling — especially important in older Mercer Island homes with hard water.
Leaking at the base or near the T&P valve? We diagnose whether the issue is a faulty valve, excessive pressure (PRV needed), or tank failure — and repair or replace accordingly.
Water heaters carry 5–15 year warranties on parts. Our Mercer Island techs look up your model and serial number to determine coverage before recommending repair vs. replacement.
If your unit is over 10 years old, we’ll give you an honest cost-benefit comparison. Sometimes a targeted repair is the right call — other times, a new efficient unit pays for itself quickly.
Energy-Efficient Water Heater Rebates for Mercer Island
Mercer Island is served by Puget Sound Energy (PSE) for both electricity and natural gas. PSE offers substantial rebates when you upgrade to an energy-efficient water heater, and these can be stacked with Federal tax credits for significant savings.
$750–$850 for ENERGY STAR-certified heat pump water heaters (Tier 2 or higher UEF). Must replace an existing electric resistance unit. Higher amount via PSE’s Efficiency Boost program for income-qualified households (up to 80% AMI).
$400–$660 for ENERGY STAR gas tankless water heaters with EF of 0.82 or higher. Applies to natural gas PSE customers replacing older gas units. Submit application with proof of purchase and installation at pse.com/rebates.
Up to $1,750 for heat pump water heaters for households up to 150% of area median income (King County). Funded by the federal IRA. Check commerce.wa.gov or wahear.com for current availability.
30% of costs up to $2,000 for heat pump water heaters; up to $600 for gas tank (EF 0.67+); up to $300 for gas tankless (EF 0.82+). Non-refundable credits — WA has no state income tax, so only federal. Can be combined with PSE rebates.
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Mercer Island Neighborhoods & Surrounding Areas We Serve
Fast Water Heater Co. provides same-day water heater installation, replacement, and repair service throughout Mercer Island. Our Washington-licensed technicians (WA L&I) cover the entire island, from North End to South End.
Inside Mercer Island
Nearby Communities
Mercer Island Water Heater FAQs
Answers to the questions Mercer Island homeowners ask us most.
Don’t see yours? Call us at the number above or request service online.
How much does water heater installation cost in Mercer Island, WA?
Installation cost in Mercer Island depends on fuel type (gas, electric, or heat pump), tank size, venting requirements, and whether code upgrades are needed for permits. Standard 40–50 gallon replacements are our most common Mercer Island job and typically complete same-day. For an exact quote, call us or request service online — we give firm pricing before any work begins, and every quote includes removal of the old unit, code-compliant installation, and City of Mercer Island Development Services filing.
Do you offer same-day water heater repair near me in Mercer Island?
Yes. Call by 12 PM and we’ll have a Washington-licensed technician at your Mercer Island address the same day in most cases. We carry common replacement parts (thermocouples, gas valves, heating elements, T&P valves, anode rods) on every truck so most Mercer Island-area repairs are completed in a single visit.
Is Fast Water Heater Co. licensed in Washington?
Yes — Fast Water Heater Co. is a fully licensed Washington contractor (WA L&I), bonded, and insured, serving Mercer Island and the Puget Sound region since 1986. Every installation is performed by Washington-licensed plumbers and pulled under the correct City of Mercer Island Development Services permit.
What water heater brands do you install in Mercer Island?
We install and service Bradford White, Rheem, A. O. Smith, Rinnai, Navien, Noritz, and Stiebel Eltron tank, tankless, and heat pump water heaters throughout Mercer Island. Our most-requested Mercer Island installs are Bradford White 50-gallon gas tanks, Rinnai tankless units, and Rheem ProTerra heat pump water heaters — which qualify for Puget Sound Energy rebates.
Do I need a permit for water heater replacement in Mercer Island?
Yes. Washington State requires a plumbing permit for every water heater replacement, issued through the City of Mercer Island Development Services for Mercer Island-area addresses. Our install price always includes pulling the permit, scheduling the inspection, and meeting the Washington State Plumbing Code — you don’t lift a finger. Skipping the permit risks fines and complicates home insurance claims, warranty coverage, and the resale of your home.
How long does a water heater installation take in Mercer Island?
Most standard tank-to-tank water heater replacements in Mercer Island take 2–4 hours from arrival to cleanup. Tankless and heat pump installations typically take 4–8 hours depending on venting runs, electrical upgrades, and condensate drainage. We schedule same-day whenever possible — call by noon and most Mercer Island homes have hot water back the same afternoon.
Do you service tankless water heaters in Mercer Island?
Yes. We install, flush, descale, and repair tankless water heaters throughout Mercer Island. Mercer Island’s older North End homes and newer South End builds both benefit from right-sized replacements — we size for household demand, not just tank gallon-for-gallon. Annual descaling protects the manufacturer warranty — most tankless units we service reach 20+ years with correct maintenance.
What areas of Mercer Island do you serve?
We serve every Mercer Island-area neighborhood, including North End, South End, East Seattle, Mercerwood, East Mercer, West Mercer, Island Park, First Hill (Mercer Island), Downtown Mercer Island, Faben Point, Bellevue, Seattle, and the surrounding communities throughout King County. Call us or request service online to confirm same-day availability at your address.
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