Best Water Heater Installation Companies in Hawaii Ranked

Choosing the right water heater for your Hawaii home is a critical decision that impacts your comfort, energy bills, and environmental footprint. The state's unique climate, high energy costs, and specific building codes make this choice more complex than on the mainland. This guide provides clear, practical information on water heater options, regulations, and costs in Hawaii, helping you make an informed decision for your household. You can use this resource to understand your options and find qualified local professionals to handle your installation or replacement project.

Roto-Rooter Plumbing & Water Cleanup

2106 Lauwiliwili St Ste 101j, Kapolei, HI 96707

Roto-Rooter Plumbing & Water Cleanup offers comprehensive residential and commercial plumbing services in Honolulu, HI. Their experienced team handles a wide range of plumbing needs, including sewer line inspections and repairs, water heater installation and repair, drain cleaning, leak detection, and gas line installation. They specialize in trenchless sewer repair and provide emergency plumbing services available 24/7 throughout the year. With expertise in floodwater cleanup and mold remediation, Roto-Rooter is equipped to manage urgent water damage situations efficiently. Serving Kapolei and surrounding communities, they combine local knowledge with advanced tools like hydro jetting to address plumbing challenges effectively.

4.9

1.5k Reviews

535 Plumbing LLC

1130 N Nimitz Hwy Suite B-180, Honolulu, HI 96817

535 Plumbing LLC is a family-owned plumbing company based in Honolulu, HI, serving residential, commercial, and new construction clients. Founded in 2015 by Shane Mizusawa, the company offers a wide range of services including water heater installation and repair, drain cleaning, sewer line repair, trenchless sewer repair, leak detection, repiping, and hydro jetting. They use advanced technology such as sewer camera inspections and pipe relining to diagnose and solve plumbing issues efficiently. 535 Plumbing is available every day, including holidays, and accommodates after-hours service requests to meet diverse scheduling needs.

4.9

597 Reviews

Pipe Masters LLC

820 W Hind Dr #240345, Honolulu, HI 96824

Pipe Masters LLC is a locally owned plumbing contractor serving Honolulu, HI, and the wider Oahu area, including outer islands. Established in 2008, they provide a wide range of plumbing services such as water heater repair and installation, drain cleaning, sewer line repair, trenchless sewer repair, leak detection, and repiping. The company uses advanced technologies including trenchless pipe replacement methods and electronic leak detection, and offers the only hot water hydro-jetting service in Hawaii. Pipe Masters also manages all necessary permits and ensures compliance with Honolulu's building codes, addressing the unique challenges posed by the island's climate and infrastructure. They provide emergency plumbing services with rapid response across Oahu.

4.9

277 Reviews

Shoreline Plumbing

honolulu

Shoreline Plumbing is a locally owned plumbing company serving Honolulu, HI, and surrounding Oahu communities. They offer a wide range of plumbing services including water heater installation and repair, drain cleaning, sewer line repair, leak detection, and fixture upgrades. The team specializes in both traditional and tankless water heaters, providing thorough inspections and reliable repairs to maintain home comfort. Shoreline Plumbing also handles sewer line assessments and root intrusion solutions to keep plumbing systems flowing smoothly. Their approach emphasizes clear communication, honest pricing, and long-lasting results, aiming to prevent recurring plumbing issues rather than quick fixes.

4.9

267 Reviews

Waialae Plumbing & Construction

825 Halekauwila St # D, Honolulu, HI 96813

Waialae Plumbing & Construction has been serving Honolulu, HI, and the entire island of Oahu since 1994. They provide a wide range of plumbing services including sewer camera inspections, water heater repair and installation, sump pump repair, drain cleaning, sewer line repair, leak detection, repiping, and toilet repair. In addition to plumbing, they are a licensed general contractor offering renovation and new construction services, allowing them to coordinate plumbing work efficiently with construction projects. Their team is experienced in handling both residential and commercial jobs, and they utilize advanced diagnostic tools for leak detection and other plumbing needs. Waialae Plumbing & Construction operates during regular business hours and does not offer after-hours or emergency services.

4.9

263 Reviews

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Hawaii's Unique Water Heating Landscape

Hawaii's approach to water heating is shaped by its commitment to energy independence and sustainability. With some of the highest electricity costs in the nation, the state has implemented forward-thinking policies to encourage the most efficient technologies ¹. The climate is a major advantage, as it allows high-efficiency systems like solar thermal and heat pump water heaters to perform exceptionally well year-round. Understanding this local context is the first step in selecting a system that will provide reliable hot water while managing long-term operating expenses.

Key Regulations and Codes

All water heater installations and replacements in Hawaii must comply with state and county codes. The State of Hawaiʻi has adopted the 2018 International Energy Conservation Code (IECC) with local amendments, which are enforced at the county level ². These codes prioritize energy efficiency and safety.

A pivotal regulation is the Solar Water Heater Mandate. For new single-family homes constructed after January 1, 2010, the installation of a solar water heating system is required by state law ^{3 4}. This underscores the state's push toward renewable energy. However, the law does allow for variances under specific conditions. A homeowner can apply for a variance if they install an instantaneous gas water heater (and have at least one other gas appliance) and can demonstrate that a solar system is not cost-effective over a 30-year mortgage period ⁴. High-efficiency heat pump water heaters are also a commonly approved alternative to solar ⁵.

Other universal requirements include:

• Permits: Permits are generally required for all new installations and replacements ⁶.
• Safety: Installations must follow manufacturer instructions and local plumbing codes, which include specifications for proper venting (for gas units), adequate access space, and the use of safety pans to contain leaks where water damage could occur ^{6 7}.
• Professional Installation: Given the complexity of codes, permits, and system-specific requirements, hiring a licensed plumbing professional is essential for a compliant and safe installation.

Types of Water Heaters in Hawaii

The combination of energy codes, utility costs, and climate makes certain water heater types more prevalent and practical in Hawaii.

Solar Water Heaters

As the mandated choice for new homes, solar thermal systems use rooftop collectors to heat water, which is stored in an insulated tank. They often include an electric or gas backup element for cloudy periods. While they have the highest upfront cost, they offer the lowest operating cost and significant long-term savings, making them a cornerstone of Hawaii's energy strategy ^{8 9}.

Heat Pump Water Heaters (HPWHs)

Often called hybrid water heaters, HPWHs are extremely efficient electric units that work like an air conditioner in reverse, extracting heat from the surrounding air to warm the water. They perform excellently in Hawaii's warm, humid climate and can use existing 240-volt electrical connections, making them a popular retrofit option. They are a leading alternative to the solar mandate and are heavily promoted through utility rebates ^{5 10}.

Traditional Electric Storage Tanks

These are the most common existing systems in older homes. They have a lower purchase price but the highest operating cost due to Hawaii's expensive electricity. They are straightforward to install where an electric tank already exists but are generally being phased out in favor of more efficient options in new construction and replacements ^{3 11}.

Tankless (On-Demand) Water Heaters

Tankless units, which can be electric or gas, heat water only when needed, eliminating standby energy loss. They provide endless hot water and are space-saving. However, electric models may require a costly electrical panel upgrade, and gas models (including propane) are less common in new residential builds unless a solar variance is obtained ^{12 13}.

Traditional Gas Storage Tanks

Natural gas or propane storage tanks can be cost-effective to operate where gas is available. However, state energy goals and codes generally discourage them in new residential construction, except as part of an approved solar variance package ^{3 4}.

Sizing Your Water Heater Correctly

Choosing the correct capacity is crucial for efficiency and comfort. An undersized unit will run out of hot water; an oversized one wastes energy.

For traditional tank-style heaters, capacity is measured in gallons. Sizing is primarily based on the number of occupants and their simultaneous hot water needs (e.g., showers running while a dishwasher is operating) ¹⁴.

For tankless systems, the key metric is flow rate, measured in gallons per minute (GPM). You must calculate the total GPM needed if multiple fixtures will be used at once and ensure the unit can provide enough temperature rise (the difference between incoming groundwater temperature and desired output) ^{12 15}. A licensed plumber can perform a detailed load calculation to ensure proper sizing for any system type.

Understanding Costs in Hawaii

Water heater costs in Hawaii vary widely based on the type of unit, its capacity, installation complexity (e.g., retrofitting, need for new electrical or gas lines), and your specific island location. The following table provides average estimated price ranges for a fully installed system, which typically includes the unit, all materials, labor by a licensed plumber, permits, and disposal of the old unit ^{16 17 18}.

Important Note: These are average ranges. Always obtain detailed, written estimates from multiple licensed Hawaii contractors for your specific project.

Rebates and Incentives

To help offset the cost of high-efficiency systems, Hawaii offers financial incentives. Hawaii Energy, the state's ratepayer-funded energy conservation and efficiency program, is the primary source for rebates ^{10 19}.

• Heat Pump Water Heaters: Significant rebates are often available for qualifying ENERGY STAR® certified HPWHs, which can reduce the net cost to be competitive with a standard electric tank ^{5 1}.
• Solar Water Heating: Rebates for solar thermal systems can be substantial, sometimes covering a meaningful portion of the installed cost. Hawaii Energy periodically updates and "supersizes" these incentives ^{8 19}.
• Federal Tax Credits: You may also qualify for federal residential energy efficiency tax credits for certain solar and heat pump installations. Check the IRS website and consult a tax professional for current details.

Always verify current program details, eligibility requirements, and rebate amounts directly on the Hawaii Energy website or by speaking with a participating contractor before making a purchase decision.

Choosing a Licensed Professional

Given the regulatory and technical complexity, selecting the right installer is as important as choosing the right unit. Look for a licensed, insured, and bonded plumbing contractor with specific experience installing the type of system you want (solar, heat pump, etc.) in Hawaii. They should be familiar with local county permit processes and able to help you navigate rebate applications. Ask for references, verify their license with the state's Department of Commerce and Consumer Affairs (DCCA), and ensure you receive a detailed, written estimate that breaks down equipment, labor, permit fees, and any other charges.

Frequently asked questions

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