APUS 190000 BTU Tankless Water Heater Review: Honest Verdict

Introduction

If you’re looking to replace a bulky storage tank water heater with a more efficient, space-saving solution, a tankless model is worth serious consideration. The APUS 190000 BTU tankless water heater review you’re about to read breaks down everything this propane-powered unit promises, from its smart connectivity to its claimed ability to run multiple showers and faucets at once. Whether you’re outfitting a new home, upgrading an older system, or simply seeking an outdoor installation that frees up indoor space, this article will help you decide if the APUS 190000 BTU is worth buying. We’ll examine its features, specifications, and real-world expectations—without relying on exaggerated claims.

This review is based on manufacturer-provided data, customer feedback, and general industry knowledge. For the most current information and to check availability, you can view the product on Amazon.

What Is the APUS 190000 BTU Tankless Water Heater?

The APUS 190000 BTU tankless water heater is an outdoor, propane-fired on‑demand water heater designed to supply hot water for an entire home. With a maximum output of 190,000 BTU and a flow rate of 8.1 gallons per minute (GPM), the manufacturer states it can support up to five outlets simultaneously—enough for three showers and two faucets. It belongs to the growing category of smart tankless heaters that offer app and remote control, making it suitable for homeowners who value temperature precision and convenience.

The unit is wall‑mounted and requires a 120‑volt AC connection for its electronic controls. It uses propane gas (a natural gas conversion kit may be available separately), and its outdoor design eliminates the need for venting through a chimney or flue in many installations, though local codes always apply.

Key Features & Specifications

Below is a summary of the most important features and technical details for the APUS propane model (SKU AP-AWH-W26LPG).

Feature	Specification
Power Source	Liquid Propane (propane gas)
Heat Output	190,000 BTU
Flow Rate	8.1 gallons per minute (GPM)
Maximum Temperature	149°F (set via controller)
Temperature Accuracy	±1°F (claimed)
Minimum Flow Rate	0.79 GPM
Dimensions (W x H x D)	6.54″ x 22.48″ x 15.51″
Voltage	120 V AC
Mount Type	Wall‑mounted
Smart Home Compatibility	Works with Tuya app (WiFi)
Warranty	2‑year full warranty on components

• Whole‑Home Capability: The 190,000 BTU output and 8.1 GPM flow are intended to provide hot water for multiple simultaneous uses—the manufacturer says three showers plus two faucets. Actual capacity depends on incoming water temperature and desired output temperature.
• Smart Temperature Control: You can adjust the water temperature from 95°F to 149°F using either a wired remote controller or the Tuya smartphone app. The claimed ±1°F stability helps avoid sudden temperature swings during use.
• Compact Outdoor Design: At roughly 22.5 inches tall and 15.5 inches wide, the unit is relatively compact and intended for outdoor wall mounting. It uses standard 3/4″ water and gas connections.
• Advanced Heat Exchanger: The manufacturer states the heat exchanger is made from 100% oxygen‑free copper, which they say offers 30% higher efficiency than conventional designs, and that intelligent staged combustion can save up to 20% in energy. These are manufacturer claims and should be evaluated in the context of your specific installation.
• All‑Weather Performance: The unit includes wind resistance rated to level 10 and electric anti‑freeze protection. It is designed to operate in harsh outdoor conditions.
• Safety Protections: Comprehensive safeguards include freeze protection, overheat protection, and flame failure shutoff. The 2‑year warranty covers all components.

What’s Included in the Box

According to the manufacturer’s product listing, the APUS 190000 BTU tankless water heater ships with the following items:

• Tankless water heater unit (1)
• Wired controller (1) with cable (10 ft, approximate)
• Mounting hardware: wall anchors (6), mounting screws (4), expandable screw (1)
• Closed circuit terminals (2)
• Installation and owner’s manual

The box does not include a gas line, water lines, or a shutoff valve. You will need to provide these separately, along with a propane supply, and must follow local building codes. The included wired controller is an important accessory because it allows temperature adjustment without relying solely on the app.

How to Use

Setup

Installation of a gas tankless water heater should be performed by a licensed professional with experience in gas appliances and local code requirements. The unit mounts on an exterior wall using the provided hardware. It requires a 120V AC power outlet, a dedicated propane gas line (typically 1/2″ or 3/4″ depending on distance), and 3/4″ water connections. The manufacturer recommends flushing the system before first use to remove any debris.

Operation

Once installed, turn on the gas supply and power the unit. Press the power button on the wired controller or use the Tuya app to set your desired temperature. When a hot water tap is opened (flow above 0.79 GPM), the heater ignites automatically and heats the water as it passes through the heat exchanger. The app allows remote temperature changes and can display usage information. The unit is designed to shut off when flow stops.

Maintenance

Regular maintenance helps prolong the heater’s life. The manufacturer recommends periodic descaling (especially in hard water areas) and cleaning of the air intake and exhaust vents. The water filter should be cleaned according to the manual. Annual inspection by a qualified technician is a good practice.

Troubleshooting

Common issues include failure to ignite (check gas supply, power, and error codes), low flow (clean the inlet filter or increase water pressure), and temperature fluctuations (verify proper gas pressure and that the flow rate is within the heater’s range). The controller displays error codes; refer to the manual for specific troubleshooting steps.

Performance & User Experience

The APUS 190000 BTU tankless water heater is designed to deliver on‑demand hot water for medium to large households, but actual performance depends on several variables. The claimed 8.1 GPM flow rate is achievable only when the incoming water temperature is warm enough (e.g., above 70°F). In colder climates, the flow rate at a given temperature rise will be lower. For example, if groundwater enters at 50°F and you need 120°F output (a 70°F rise), a 190,000 BTU heater can deliver approximately 5–6 GPM. That’s still enough for two showers running simultaneously, but not the full 8.1 GPM.

The smart app and remote controller are notable conveniences. Many users appreciate being able to adjust the temperature without walking outside. The ±1°F stability claim is common among modern tankless heaters; actual stability depends on consistent water flow and gas pressure.

The outdoor installation eliminates venting complexity but exposes the unit to weather. The wind resistance rating (up to level 10) and electric anti‑freeze protection address common outdoor concerns, but extreme temperatures may still affect performance.

Customer reviews on platforms like Amazon show an average of 4.3 out of 5 stars from 42 ratings as of the time of this review. Positive comments often highlight the compact size, temperature consistency, and ease of use. Some users have noted that installation requires careful attention to gas line sizing and that the customer support response can be slow. As with any product, individual experiences vary.

Pros and Cons

Pros

• High BTU output suitable for multiple simultaneous uses in many homes.
• Smart app control and included wired controller for convenient temperature adjustment.
• Compact design reduces clutter compared to traditional tank heaters.
• Low minimum flow rate (0.79 GPM) helps it activate even with low water pressure.
• Wind‑resistant and anti‑freeze features support outdoor installation.
• 2‑year comprehensive warranty.

Cons

• Outdoor installation may not be suitable in extremely cold climates without additional freeze protection.
• Actual flow rate at high temperature rises is lower than the maximum 8.1 GPM—important to understand for cold‑inlet conditions.
• Installation requires a licensed professional, adding to overall cost.
• App and smart features rely on stable WiFi; some users report connectivity issues.
• Customer service responsiveness has been mixed in some user reports.
• No natural gas version included (must purchase separately or convert, if supported).

Comparison With Alternatives

While we do not provide pricing, we can compare the APUS 190000 BTU unit to other popular tankless water heaters on the market. Below are three alternatives that serve similar whole‑home needs.

Model	BTU	Max GPM	Fuel Type	Key Difference
APUS 190,000 BTU	190,000	8.1	Propane	Smart app control, compact outdoor design
Rheem RTG-84D-XL	199,000	8.4	Natural Gas / Propane	High flow rate, indoor/outdoor, longer track record
Ecosmart ECO 27	27 kW (equivalent ~92,000 BTU)	6.5	Electric	Electric, no gas line needed, lower flow
Rinnai RL94i	180,000	9.8	Natural Gas / Propane	High flow, advanced circ pump, larger footprint

The APUS model stands out for its combination of smart controls and relatively compact size. However, established brands like Rheem and Rinnai offer proven reliability and more extensive service networks. The best choice depends on your fuel type, space constraints, and budget.

Who Should Buy This Product?

Ideal users:

• Homeowners who want to replace a large tank water heater with an outdoor, space‑saving unit.
• Households with moderate to high hot water demand (up to three showers at once) in moderate climates.
• Tech‑savvy users who appreciate app‑based temperature control and monitoring.
• Those with existing propane infrastructure (or willing to install a propane tank).

Not ideal for:

• Very cold climates where incoming water temperature drops below 40°F, as flow rates will be significantly reduced.
• Homes without a reliable 120V outlet near the installation site.
• Users who prefer a natural gas model without conversion kits.
• Anyone seeking a heater that can run six or more simultaneous outlets at full flow.

Expert Tips

• Always size your tankless water heater based on the coldest incoming water temperature in your region, not the average. Use a BTU calculator to estimate required capacity.
• Install a whole‑house water softener if you have hard water; tankless heat exchangers are prone to scale buildup that reduces efficiency.
• Use the wired controller as your primary temperature interface. The app is convenient but may lose connection during power or WiFi outages.
• Schedule annual maintenance with a qualified technician to clean the burner, check gas pressure, and flush the system.
• Ensure the outdoor mounting location is sheltered from direct rain and snow to maximize the life of the electronic components.

Common Mistakes

1. Undersizing the gas line – A long or undersized propane line can cause insufficient gas pressure, leading to flame failure or low output.
2. Ignoring venting requirements – Even for outdoor models, some local codes require clearances from windows, doors, and corners.
3. Not flushing before first use – Debris in the water lines can damage the heat exchanger. Always follow the manufacturer’s flushing procedure.
4. Setting the temperature too high – 149°F is very hot and increases the risk of scalding. Use lower settings (around 120°F) unless you have a mixing valve.
5. Relying solely on the app for operation – If the app fails, you may not be able to adjust temperature without the wired controller. Keep the controller accessible.
6. Neglecting freeze protection in extreme cold – While the unit has anti‑freeze features, sustained sub‑freezing temperatures can still cause damage if the unit is not drained or insulated properly.

Where to Buy

The APUS 190,000 BTU propane tankless water heater is available through various online retailers. The most common source is Amazon, where the product listing includes detailed specifications, customer reviews, and stock information. Because availability and prices can change, it’s a good idea to check directly with the seller.

Final Verdict

The APUS 190000 BTU tankless water heater is a capable, feature‑rich option for homeowners seeking an outdoor propane‑powered whole‑home solution. Its smart controls, compact footprint, and generous claimed output make it attractive for medium to large households with moderate hot water demands. However, like all tankless heaters, its real‑world performance depends heavily on incoming water temperature and proper installation.

If you value smart connectivity and want to reclaim indoor closet space, the APUS unit is worth considering. For those in colder regions or with very high simultaneous flow needs, a larger unit from an established brand might be a safer bet. The 2‑year warranty provides some peace of mind, but be prepared for the upfront cost of professional installation.

Overall, the APUS 190000 BTU tankless water heater review concludes that it offers good value for its intended use case, but we recommend verifying your specific flow and temperature rise requirements before purchasing.

FAQ

Does the APUS 190000 BTU work with natural gas?

The unit as sold is configured for liquid propane. Some models may be convertible with a manufacturer‑supplied conversion kit; check with the seller or APUS directly for natural gas compatibility.

Can this heater be installed indoors?

The manufacturer specifies this as an outdoor unit. Indoor installation would require professional evaluation of venting and clearances, and is generally not recommended without explicit approval.

What is the minimum water flow to activate the heater?

The minimum flow rate is 0.79 GPM, which is lower than many tankless heaters. This allows it to turn on even with a single low‑flow faucet.

Does the unit come with a gas line or water connections?

No. You must purchase gas line (use black iron or flexible gas piping per code) and water lines (3/4″ NPT connections are standard). A qualified plumber or gas fitter should handle the connections.

How do I clean the water filter?

The water inlet filter should be removed and cleaned every few months. Refer to the manual for exact location and procedure. A soft brush and water are usually sufficient.

What error codes might appear on the controller?

Common error codes include E1 (ignition failure), E2 (overheat), and E4 (flame failure). The manual provides a full list and suggested fixes. If an error persists, contact APUS support.

Can I use the app without the wired controller?

Yes, the app works independently as long as the unit is connected to WiFi. However, the wired controller is included and recommended for direct local control.

Is the warranty transferable?

Warranty terms typically apply to the original purchaser. Check the included warranty card for details on transferability.

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