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Indirect water heaters are gaining popularity due to their efficiency and cost-saving benefits. Essentially, these heaters use the main furnace or boiler to heat a fluid that’s circulated through a heat exchanger in the storage tank.
With top brands in this category are Weil-McLain, Bradford White, HTP, and SuperStor. While the initial cost might be higher than traditional water heaters, many homeowners find the long-term savings on energy bills make them worth the investment.
Especially in areas with hard water, the best residential indirect water heaters can offer longer lifespans and better performance. Brands like Buderus, Triangle Tube, IBC, and Amtrol have been recognized for their quality.
On the other hand, some people might compare indirect water heaters with tankless systems, but each has its own set of advantages. It’s essential to research and evaluate based on individual needs before making a decision.
Indirect Water Heater: A Worthy Investment?
Indirect water heaters have become a popular choice for many homeowners. But the question remains: is it a worthy investment? Let’s break it down.
Cost Versus Benefits Analysis
Indirect water heaters might have a higher initial cost compared to traditional water heaters. However, the benefits they offer, such as energy efficiency and longer lifespan, often outweigh the initial investment. Over time, the reduced energy bills can lead to significant savings, making the cost per use of an indirect water heater much less than its counterparts.
The Promise of Long-Term Energy Savings
One of the standout features of indirect water heaters is their energy efficiency. They utilize the main furnace or boiler to heat water, which means they don’t require a separate energy source. This design leads to less energy consumption and, consequently, reduced energy bills.
Fitting Different Households
Indirect water heaters are versatile. They can be integrated into various heating systems, making them suitable for different households. Whether you have a large family home or a cozy apartment, there’s an indirect water heater that can cater to your needs.
Top 7 Indirect Water Heater Reviews
1. Amtrol 80 Gallon WHS-80Z BoilerMate Premier Series Indirect-Fired Water Heater
- Capacity: 80 Gallons
- Material: Stainless Steel, Plastic
- BTU Output: 40000
- Dimensions: 26″W x 66″H
- Weight: 170 lbs
Key Features
- Electromechanical thermostat
- High grade 316-L stainless steel
- Thick urethane foam insulation
- High flow domestic water connections
- Removable Heat Exchanger
- Multiple pass design
- Rugged, dent-resistant outer jacket
Specialty
- Resists aggressive water conditions
- Loses <0.5°F/hr in standby
- Minimal pressure drop design
Compatible For
- Large homes
- High-end installations
- Plumbing applications
Need to Improve
- The price might be steep for some
The Amtrol 80 Gallon WHS-80Z BoilerMate is a top-tier indirect water heater, perfect for those seeking high-end installations. Its robust design and high-grade materials ensure longevity and efficient performance.
2. Triangle Tube SMART40 Phase III Indirect 36-Gallon Water Heater
- Capacity: 36 Gallons
- Material: Stainless Steel, Polyurethane
- Dimensions: 22 x 22 x 46 inches
- Weight: 135 Pounds
Key Features
- Exclusive “Tank-in-Tank” Technology
- Abundant Domestic Hot Water
- 2″ Polyurethane Foam Insulation
- Lowest Pressure Drop in Industry
- Self-Cleaning Heat Exchanger
- Self Descaling Heat Exchanger
- Environmentally sound solutions
Specialty
- Efficient hot water provision
- Industry-leading innovations
- Over 60 years of quality
Compatible For
- Industry-standard installations
- Environmentally-conscious households
- Modern plumbing systems
Need to Improve
- Limited capacity for larger homes
Triangle Tube’s SMART40 Phase III offers innovative “Tank-in-Tank” technology, ensuring an efficient and abundant hot water supply. With over 60 years in the industry, it’s a trusted choice for modern households.
3. HTP SSU45 SuperStor Ultra Stainless Steel Water Storage Tank
- Capacity: 45 Gallons
- Material: Stainless Steel
- Weight: 64 Pounds
Key Features
- Quality 316L stainless steel tank
- Environmentally safe water-blown insulation
- Heat losses <1°F per hour
- Suitable for various applications
- 10-Year Limited Warranty
- Increases storage capacity
- Resists corrosion
Specialty
- Efficiently maintains hot water
- Suitable for commercial or residential
- High-quality stainless steel construction
Compatible For
- Any hot water system
- Commercial applications
- Residential applications
Need to Improve
- Complaint about little support from HTP on issues
The HTP SuperStor Ultra 45 45-gallon water Tank is a reliable and efficient choice for those looking to enhance their hot water system. Its stainless steel construction ensures durability and efficient heat maintenance.
4. Bradford White 75 Gallon – Residential PowerStor2 Series Double Wall Energy Saver Indirect Water Heater
- Capacity: 75 Gallons
- Material: Glass
- BTU Output: 65000
- Dimensions: 24″W x 59″H
- Weight: 224 lbs
Key Features
- Double wall 1 1/2″ O.D. glass-coated coil
- Low Heat Exchanger Head Loss
- Factory-installed Hydrojet Total Performance System
- Vitraglas Lining for protection
- Fully Automatic Controls
- T&P Relief Valve Included
Specialty
- Efficient heat exchange with low head loss
- Minimizes sediment build-up in the tank
- Stand-by Heat Loss <0.5°F per hour
Compatible For
- Boiler, heat pump, solar heating systems
- Residential applications
- Modern plumbing systems
Need to Improve
- Nothing noticeable
The Bradford White 75 Gallon PowerStor2 Series offers a double-wall heat exchanger design, ensuring an efficient and consistent hot water supply. Its advanced features make it a top choice for modern households and heating systems.
5. Burnham AL70SL Alliance Hydrastone-Lined Indirect Water Heater
- Capacity: 70 Gallons
- Material: Alloy Steel
- BTU Output: 120000
- Dimensions: 28″W x 45.75″H
- Weight: 300 lbs
Key Features
- Hydrastone-lining protection
- Efficient heat losses <1°F per hour
- 10-year full tank replacement warranty
- Suitable for various applications
- Maximum First Hour Rating at 135°F: 294
- Continuous Draw Rating at 135°F: 217
- Maximum Allowable Working Pressure: 150 psi
Specialty
- Unique Hydrastone-lining protection
- Efficiently maintains hot water
- Suitable for commercial or residential
Compatible For
- Any hot water system
- Commercial applications
- Residential applications
Need to Improve
- Potential longevity concerns
The Burnham AL70SL Alliance offers a unique Hydrastone lining, ensuring an efficient and consistent hot water supply. Its alloy steel construction ensures durability and efficient heat maintenance.
6. Lochinvar 40 Gallon, Squire SIT040 Indirect Water Heater
- Capacity: 40 Gallons
- Material: Stainless Steel
- BTU Output: 115000
- Dimensions: 20″W x 55.5″H
- Weight: 105 lbs
Key Features
- Fully Welded Construction
- 100% Stainless Steel Construction
- 316L Passivated Stainless Steel Tank
- 304L Stainless Steel Heating Coil
- Non-HCFC High-Density Foam Insulation
- Temperature and Pressure Relief Valve
Specialty
- Efficient heat exchange with low head loss
- Minimizes sediment build-up in the tank
- Stand-by Heat Loss <0.5°F per hour
Compatible For
- Boiler, heat pump, solar heating systems
- Residential applications
- Modern plumbing systems
Need to Improve
- Potential longevity concerns
Review: The Lochinvar 40 Gallon Squire SIT040 offers a fully welded stainless steel construction, ensuring an efficient and consistent hot water supply. Its advanced features make it a top choice for modern households and heating systems.
7. Weil-McLain Aqua-Pro 80 Indirect Water Heater
- Capacity: 80 Gallons
- Material: Brass
- BTU Output: 199000
- Dimensions: 28″W x 53.5″H
- Weight: 125 lbs
Key Features
- Lightweight, easily maneuvered non-metallic tank
- No anode, no annual maintenance
- Convenient top connections
- Seamless tank construction, no welds
- Digital temperature control
- Removable copper finned high-output coil
- Durable brass drain valve
Specialty
- Efficient heat exchange with low head loss
- Minimizes sediment build-up in the tank
- Stand-by Heat Loss <0.5°F per hour
Compatible For
- Boiler, heat pump, solar heating systems
- Residential applications
- Modern plumbing systems
Need to Improve
- Brass material might be less durable
- Brand not specified, potential quality concerns
The Weil-McLain Aqua-Pro 80 offers a unique lightweight design with a brass construction, ensuring an efficient and consistent hot water supply. Its advanced features make it a top choice for modern households and heating systems.
Buying Guide: Best Indirect Water Heater
Navigating the market for the ideal indirect water heater can be a challenge, given the myriad of options available. This guide aims to streamline your decision-making process by highlighting the critical features to consider.
Efficiency Rating: A top priority should be the unit’s efficiency rating. A higher rating indicates that the heater will use less energy, leading to potential savings on utility bills. Look for models with an Energy Star certification, a mark of energy efficiency.
Tank Capacity: The size of your household and your daily hot water needs will determine the ideal tank capacity. Larger families or homes with multiple bathrooms might require a heater with a larger tank, ensuring everyone gets their fair share of hot water.
Material and Construction: The longevity of your indirect water heater largely depends on its construction. Stainless steel tanks are popular for their corrosion resistance, while stone-lined tanks offer protection against highly acidic water.
Heat Exchanger Quality: The heat exchanger is a pivotal component, transferring heat from the boiler to the water in the tank. Opt for models with a high-quality, durable heat exchanger to ensure efficient heat transfer and prolonged service life.
Warranty and Support: A robust warranty can be a testament to the manufacturer’s confidence in their product. It’s wise to opt for heaters that come with extended warranties, covering the tank, parts, and sometimes even labor.
Installation Flexibility: Some heaters offer more flexibility in terms of installation, allowing for both horizontal and vertical setups. Depending on your space constraints, this might be a feature to consider.
The Mechanics Behind Indirect Water Heaters
Foundational Principles: At its core, an indirect water heater uses the home’s main heating system to warm up water. It doesn’t have its own heating element. Instead, it relies on the heat produced by the furnace or boiler.
The Central Role of Furnaces and Boilers: The furnace or boiler plays a pivotal role in the functioning of an indirect water heater. It heats a fluid, usually water, which then circulates through a heat exchanger in the storage tank of the water heater, thereby warming the water inside.
Functionality of the Heat Exchanger: The heat exchanger is a crucial component of an indirect water heater. It transfers the heat from the fluid heated by the boiler or furnace to the water in the storage tank without the two ever coming into direct contact. This efficient heat transfer process is what makes indirect water heaters so energy-efficient.
Setting Up Your Indirect Water Heater
Installation Steps
Installing an indirect water heater involves connecting it to the main heating system, setting up the heat exchanger, and ensuring all connections are secure. It’s essential to follow the manufacturer’s guidelines to ensure the system works efficiently.
Professional Installation or DIY?
While some homeowners might be tempted to install the heater themselves, it’s often recommended to hire a professional. They have the expertise to ensure the installation is done correctly, safely, and in compliance with local regulations. A proper installation can also ensure the longevity and efficiency of the system.
Essential Tools and Equipment
For those who opt for DIY installation, having the right tools is crucial. This includes wrenches, pipe cutters, soldering tools, and safety gear. Always refer to the manufacturer’s manual for a detailed list of required tools and equipment.
Maintaining Your Indirect Water Heater
Routine maintenance of your indirect water heater is essential to ensure its longevity and optimal performance. Following the manufacturer’s guidelines can help in keeping the system running efficiently.
Regular cleaning, especially of the heat exchanger, can prevent mineral build-up, which can hinder the heater’s efficiency. Using soft water or installing a water softener can also reduce the chances of mineral deposits.
Regular check-ups, ideally annually, by a professional can help in identifying potential issues before they become major problems.
These check-ups can include inspecting for leaks, checking the pressure, and ensuring that all components are functioning correctly.
Indirect vs. Tankless: The Showdown
Indirect water heaters and tankless water heaters are both popular choices, but they serve different needs. Indirect heaters use the home’s main heating system to heat water, while tankless systems heat water on demand.
In terms of energy efficiency, indirect heaters often have the edge as they utilize the already-running furnace or boiler. However, tankless systems can be more efficient in homes where hot water usage is sporadic.
Cost-wise, while indirect heaters might have a higher initial cost, their energy savings over time can make them a more economical choice in the long run.
Optimizing Your Heater’s Performance
For the best performance from your indirect water heater, it’s essential to follow best practices. This includes setting the right temperature, ensuring proper insulation, and not overburdening the system.
Contrary to some myths, turning the heater off when not in use might not save energy, as the system will use more energy to heat the water from cold. Safety is paramount, so always ensure that safety valves are functioning and that the system is not under undue pressure.
Regularly checking for leaks and ensuring that the system is grounded can also prevent potential hazards.
using Indirect Water Heater: pros and cons
Pros:
- Energy Efficiency: Indirect water heaters are known for their energy-saving capabilities. They utilize the main furnace or boiler to heat the water, which means there’s no need for a separate burner. This can lead to significant energy savings over time.
- Durability: These heaters tend to have a longer lifespan compared to their direct counterparts. The absence of a standalone burner means fewer parts are exposed to constant heat, reducing wear and tear.
- Consistent Hot Water Supply: With a well-sized unit, households can enjoy a steady supply of hot water, especially during peak usage times.
- Space-saving: Since they use the home’s main heating system, there’s no need for a separate burner or vent, saving valuable space.
Cons:
- Initial Cost: The upfront cost of an indirect water heater can be higher than direct-fired models. This might deter some homeowners from investing.
- Dependence on Main Heating System: If the main boiler or furnace fails, you’ll be without hot water. This interdependence can be a drawback for some.
- Maintenance: While they’re durable, indirect water heaters still require regular maintenance to ensure they run efficiently. Neglecting this can lead to decreased performance over time.
Frequently Asked Questions
How Long Does an Indirect Water Heater Last?
Typically, an indirect water heater can last anywhere from 12 to 20 years, depending on the quality of the unit, the water quality in your area, and how well it’s maintained.
Can I Use an Indirect Water Heater with a boiler?
Most indirect water heaters are designed to be compatible with a variety of boilers. However, it’s essential to check the specifications and consult with the manufacturer or a professional before pairing with a specific boiler.
Is an Indirect Water Heater Environmentally Friendly?
Yes, indirect water heaters are generally considered environmentally friendly due to their high efficiency. They utilize the heat from a boiler, which means they consume less fuel compared to direct-fired water heaters.
What’s the Initial Cost of an Indirect Water Heater?
The initial cost can vary based on the brand, size, and features. While they might be more expensive upfront compared to direct-fired units, they can offer savings in the long run due to their efficiency.
Do Indirect Water Heaters Need Electricity?
While the indirect water heater itself doesn’t produce heat using electricity, it might require power for controls or pumps, depending on the system setup.