Introduction

If you’re in the market for a tankless water heater that can handle the demands of a busy household without taking up valuable indoor space, the APUS 190000 BTU Outdoor Tankless Water Heater is a unit that likely appears on your radar. Designed to deliver on-demand hot water for multiple fixtures simultaneously, this propane-powered model promises whole-home convenience with smart control features. In this APUS 190000 BTU tankless water heater review, we take a detailed look at its specifications, claimed performance, and real-world considerations to help you decide if it’s the right fit for your home. Whether you’re upgrading from a traditional storage tank or building new, we aim to provide an honest and balanced assessment.

If you want to explore the product directly, you can check the APUS 190000 BTU on Amazon for the latest details and customer feedback.

What Is the APUS 190000 BTU Tankless Water Heater?

The APUS 190000 BTU tankless water heater is an outdoor, propane-powered instant hot water system designed for whole-home use. It belongs to the category of tankless (on-demand) water heaters, meaning it heats water only when needed rather than storing a tank of hot water. This specific model is rated at 190,000 BTU and delivers up to 8.1 gallons per minute (GPM), which the manufacturer states can support three showers and two faucets simultaneously. It is targeted at homeowners looking to replace a traditional water heater or those building new homes who prefer the space savings and energy efficiency of tankless technology.

The unit is also compatible with natural gas (via conversion, though the primary configuration discussed here is propane) and includes smart features such as WiFi control through the Tuya app and a wired remote controller. Its outdoor installation design eliminates the need for venting through the roof, which can simplify setup.

Key Features & Specifications

Below is a breakdown of the most notable features and specifications as provided by the manufacturer. All claims are based on the product listing and should be verified with your specific installation conditions.

Core Specifications

Specification	Value
Power Source	Liquid Propane (also convertible to Natural Gas)
BTU Rating	190,000 BTU
Max Flow Rate	8.1 GPM
Temperature Range	95°F – 149°F
Temperature Accuracy	±1°F
Minimum Flow to Activate	0.79 GPM
Dimensions (WxHxD)	6.54 x 22.48 x 15.51 inches
Voltage	120V AC
Water/Gas Connections	3/4 inch NPT
Mount Type	Wall-mounted (outdoor)
Smart Home Compatibility	Tuya App (WiFi), Wired Remote
Warranty	2-year full warranty on components

Highlighted Features

Whole-Home Hot Water Delivery: The unit is rated to supply up to three showers and two faucets simultaneously, making it suitable for medium to large households.
Smart Temperature Control: Users can adjust the water temperature remotely via the Tuya app or a wired controller, with a claimed accuracy of ±1°F.
Advanced Heat Exchanger: The heat exchanger is made of 100% oxygen-free copper, which the manufacturer says is 30% more efficient than conventional materials, and uses intelligent staged combustion for 20% energy savings.
Low Water Pressure Startup: With a minimum activation flow of 0.79 GPM, the heater can operate in homes with weak water pressure.
All-Weather Performance: Built with wind-resistant construction (10-level wind rating) and electric anti-freeze protection, intended for outdoor use in harsh climates.
Safety Protections: Includes freeze protection, overheat protection, flame failure safeguard, and a 2-year full warranty.

What’s Included in the Box

According to the product listing, the APUS tankless water heater comes with the following items:

APUS Tankless Water Heater (unit itself)
Wired Controller with cable (optional – may be included in the box)
Screws, wall anchors, mounting screws for installation
Closed circuit terminal connectors
Installation and Owner’s Manual
Expandable screw and additional hardware

The setup is intended for outdoor wall installation. The unit requires a 120V AC electrical connection, standard 3/4-inch water and gas lines, and a propane supply. Note that professional installation by a licensed plumber or gas fitter is generally recommended for tankless water heaters to ensure safety and proper performance.

How to Use

Setup

Before installation, ensure the location meets clearance requirements and local building codes for outdoor gas appliances. The unit must be mounted on a sturdy wall capable of supporting its weight. Connect the water supply lines (cold in, hot out) and the propane gas line, then plug in the 120V power cord. The wired controller can be mounted inside the home for convenient access. If using the WiFi feature, download the Tuya app and follow the pairing instructions. Note that all gas and water connections should be leak-tested before first use.

Operation

Once installed and powered on, the heater will automatically ignite when a hot water tap is opened and the flow exceeds the minimum activation threshold (0.79 GPM). The temperature can be adjusted using the wired controller or the app. The unit is designed to maintain a steady outlet temperature within ±1°F of the set point, though actual performance may vary depending on incoming water temperature and flow rate.

Maintenance

Routine maintenance includes periodically flushing the heat exchanger to remove mineral buildup, especially in areas with hard water. The manufacturer recommends checking the air intake and exhaust vents for obstructions. The external housing can be cleaned with a damp cloth. For long-term reliability, follow the maintenance schedule in the owner’s manual.

Troubleshooting

Common issues include failure to ignite (check gas supply, propane tank, or power), fluctuating water temperature (often due to undersized gas line or simultaneous high usage), and error codes (refer to manual). The app may also provide diagnostic information. If problems persist, contact APUS customer support.

Performance & User Experience

In terms of specifications, a 190,000 BTU unit with 8.1 GPM is generally suitable for a home with up to three bathrooms, depending on ground water temperature. In warmer climates, it can handle more simultaneous draws; in colder regions, the flow rate may need to be reduced to achieve the desired temperature rise. The manufacturer’s claim of supporting 3 showers + 2 faucets assumes average flow rates and moderate temperature rise (e.g., from 50°F to 105°F).

The minimum activation flow of 0.79 GPM is relatively low, which can be beneficial for homes with low water pressure or for using the heater with low-flow fixtures. However, some users have reported that in very low-flow situations (e.g., single bathroom sink), the heater may cycle on and off. This is a common characteristic of many tankless units.

The smart control via the Tuya app offers convenience, such as preheating the water before a shower or adjusting temperature from a smartphone. However, app reliability can depend on WiFi strength and device compatibility. The wired controller is a reliable backup.

Customer reviews on Amazon show an average rating of 4.3 out of 5 stars (42 ratings). Positive feedback often highlights the unit’s compact size, ease of installation (for those with plumbing experience), and consistent hot water output. Some negative reviews mention issues with the app connectivity or difficulty finding replacement parts. As always, individual experiences vary.

Pros and Cons

Pros

High flow rate (8.1 GPM) suitable for multiple simultaneous uses.
Smart features (WiFi and wired remote) allow convenient temperature adjustments.
Low minimum flow rate (0.79 GPM) helps with low-pressure systems.
Outdoor installation saves indoor space and eliminates venting complexities.
Energy-efficient design with copper heat exchanger and staged combustion (claimed 20% savings).
All-weather protection including wind resistance and anti-freeze.
Comprehensive safety features and a 2-year warranty.

Cons

Propane dependency means ongoing fuel costs and tank refills or a large propane tank.
Requires electricity to operate; will not function during a power outage unless backed up.
Installation complexity generally requires a professional for gas lines and electrical.
App performance can be inconsistent according to some user reports.
Limited availability of servicing – APUS is a newer brand in the water heater market, so local service may be scarce.
Flow rate degrades with colder incoming water – in northern climates, the unit may not achieve 8.1 GPM at high temperature rises.

Comparison With Alternatives

When evaluating the APUS 190000 BTU unit, it’s useful to compare it with other popular tankless water heaters in a similar price range (note: pricing not included).

Feature	APUS 190000 BTU	Rinnai RL94i (Natural Gas/LP)	EcoSmart ECO 27 (Electric)
Type	Propane (outdoor)	Gas (indoor/outdoor)	Electric (indoor)
BTU / Power	190,000 BTU	199,000 BTU	27 kW (approx 92,000 BTU)
Max GPM	8.1 GPM	9.8 GPM	4.5 GPM (at 60°F rise)
Min Flow Activation	0.79 GPM	0.4 GPM	0.3 GPM
Smart Controls	App + Remote	Optional WiFi module	None (only manual)
Warranty	2 years (full)	12 years (heat exchanger)	Lifetime (on parts)
Mounting	Outdoor wall	Indoor/outdoor	Indoor wall

The Rinnai RL94i is a well-known competitor with higher flow rates and a longer heat exchanger warranty, but it typically costs more. The EcoSmart ECO 27 is an electric option that avoids gas lines but has lower flow rates and requires a heavy-duty electrical circuit. For homeowners looking for a propane solution with smart features, the APUS offers a compelling balance of performance and cost (not stated).

Who Should Buy This Product?

Ideal Users

Homeowners with existing propane supply or willing to install a propane tank.
Those who want to replace a bulky storage tank water heater with an outdoor unit to free up indoor space.
Households with moderate to high hot water demand (2-3 bathrooms).
Tech-savvy users who appreciate app-based temperature control.
People living in areas with moderate winter climates (though the unit has freeze protection, extreme cold may still affect performance).

Not Ideal Users

Homes that rely solely on natural gas without easy propane conversion.
Those who prefer professional installation with a widely serviced brand (APUS service network may be limited).
Households with very cold incoming water temperatures (e.g., below 40°F) that require high flow rates at high temperature rises.
People who want a completely electricity-free gas water heater (this unit needs 120V).

Expert Tips

Size your gas line properly: The APUS 190,000 BTU unit requires a gas line capable of delivering sufficient propane volume. Use a licensed professional to calculate the correct pipe diameter and avoid pressure drops.
Consider a water softener: In hard water areas, mineral scale can reduce heat exchanger efficiency. Installing a whole-house softener or using a descaling kit periodically will extend the unit’s life.
Mount with clearance for service: Follow the manual’s clearance requirements for air intake and exhaust. Outdoor units need protection from debris and snow accumulation.
Test the app before finishing installation: Pair the WiFi early so you can troubleshoot connectivity while the unit is still accessible.
Monitor the temperature rise: Use a thermometer at the tap to verify the actual output temperature. If it’s consistently lower than set, you may need to reduce flow rate or insulate hot water pipes.

Common Mistakes

Undersizing the gas line – leads to poor performance or ignition failure. Always have a contractor calculate load.
Installing without a permit – many jurisdictions require permits and inspection for gas and water heater installations.
Neglecting to flush the heat exchanger – annual flushing with vinegar or descaling solution prevents scale buildup.
Mounting the unit in an enclosed space – outdoor units need open air for combustion and ventilation; never install in a garage or shed without proper vents.
Using too many fixtures at once – while the unit claims 3 showers + 2 faucets, actual performance depends on flow rates and ground water temperature. Test your home’s simultaneous demand.
Ignoring error codes – the unit displays faults; consult the manual before resetting repeatedly.

Where to Buy

The APUS 190000 BTU tankless water heater is available through major online retailers. For the most current stock, pricing, and customer reviews, you can visit the product page on Amazon. It may also be listed on other home improvement sites, but availability can vary.

View Product on Amazon

Final Verdict

The APUS 190000 BTU Outdoor Tankless Water Heater presents a solid choice for homeowners seeking a propane-powered, smart-controlled, high-output unit. Its combination of 8.1 GPM flow rate, low activation flow, and outdoor design make it a practical upgrade from a traditional tank. The smart features add convenience, while the all-weather build and safety protections aim to ensure reliable operation.

However, it’s important to have realistic expectations: the unit’s performance is dependent on proper installation, adequate gas supply, and local water conditions. The brand is relatively new, so support and service availability may be less extensive than established names like Rinnai or Rheem. If you are comfortable with a DIY-friendly installation (or have a good contractor) and value smart home integration, this APUS model is worth considering.

Overall, for its feature set and claimed efficiency, the APUS 190000 BTU tankless water heater earns a cautious recommendation – but we advise verifying compatibility with your home’s specific needs before purchasing.

FAQ

1. Can the APUS 190000 BTU water heater be used indoors?

No, this model is designed for outdoor installation only. Using it indoors without proper venting could be dangerous.

2. Does it work with natural gas?

The unit is configured for liquid propane out of the box, but the manufacturer states it can be converted for natural gas (conversion kit may be required). Check the product details or contact APUS for compatibility.

3. What is the minimum water flow needed to activate the heater?

The minimum activation flow is 0.79 GPM. If you have low-flow fixtures, the heater may not turn on. Some users have reported that very low flow (e.g., trickle) may not trigger ignition.

4. How do I control the water temperature remotely?

You can use the Tuya app (WiFi) to adjust temperature, or the included wired remote controller. The app also allows scheduling and monitoring.

5. Is the APUS water heater Energy Star certified?

This specific model does not appear to be Energy Star certified according to the product listing. However, all tankless water heaters are generally more efficient than storage tanks.

6. What is the warranty?

APUS offers a 2-year full warranty on all components. This is shorter than some competitors (which may have 10-12 years on heat exchangers).

7. Can it supply hot water during a power outage?

No, because it requires 120V AC electricity to operate the control board and ignition system. A backup power source would be needed.

8. How often should I flush the unit?

Manufacturer recommendations vary, but for homes with hard water, annual flushing with a descaling solution is advisable. In soft water areas, every 2-3 years may suffice.

Stay Informed

If you found this APUS 190000 BTU water heater review and rating helpful, consider subscribing to our newsletter for more honest product reviews, energy efficiency tips, and home improvement guides. We curate helpful content to help you make smarter purchasing decisions.

Affiliate Disclosure

This article contains affiliate links. As an Amazon Associate, I earn from qualifying purchases. This means I may receive a small commission at no extra cost to you if you click through and make a purchase. I only recommend products I have researched and believe may be valuable to readers. Your support helps maintain this site. For more information, see our full disclosure policy.