AO Smith Adapt SC ATM-199X3 Tankless Water Heater With X3 Scale Prevention – 199,000 BTU
From $3,679.00
AO Smith ATM-199X3 Tankless With X3® Protection
The AO Smith Adapt SC ATM-199X3 delivers up to 199,000 BTU/hr and 10.5 GPM of continuous hot water, with integrated X3® Scale Prevention that extends the life of the heat exchanger and eliminates annual descaling.
All-Inclusive Installation
Our price includes: full supply and installation by licensed City Home Comfort technicians across Toronto and the GTA.
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- 🔧 Standard Installation & System Startup
- 🛠️ 5-Year Parts & Labour Warranty (City Home Comfort)
- 🏅 ENERGY STAR® Certified – 0.95 UEF
- ⚙️ Indoor or Outdoor Installation (with kit)
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Warranty & Installation
Our pricing includes all equipment, materials, and installation time required for a professional setup of your new system. We strictly adhere to the manufacturer’s specifications to ensure optimal performance and the right equipment fit for your home. Each system is thoroughly tested and commissioned on-site.
We are committed to the quality of our workmanship and the products we install. That’s why our systems come with some of the most comprehensive warranty coverage in the industry. The installation price includes the standard manufacturer’s warranty, with the option to extend it to cover any labour costs for future repairs.
Product Description
AO Smith ATM-199X3 Tankless Water Heater With X3® Scale Prevention
The AO Smith Adapt™ SC ATM-199X3 is a high-efficiency, ultra-low NOx tankless water heater that delivers reliable, endless hot water while reducing energy use and maintenance. With an output of up to 199,000 BTU/hr and a max flow rate of 10.5 GPM, it’s ideal for larger households or homes with high simultaneous hot water demand.
Featuring integrated X3® Scale Prevention Technology, this model helps prevent scale build-up on the heat exchanger—extending lifespan and eliminating the need for annual descaling.
✔️ Professional Local Installation Across Toronto & GTA
City Home Comfort supplies and professionally installs the AO Smith ATM-199X3 with licensed in-house technicians. We handle everything from removing the old unit to final startup and commissioning.
- On-site inspection and layout review
- Full installation of AO Smith ATM-199X3 with X3® technology
- Connection to existing gas, water, and condensate lines (standard scope)
- Vent system setup using 2″ or 3″ PVC/CPVC as required
- Startup, testing, and commissioning
- Manufacturer registration and warranty documentation
- Old unit removal and cleanup
*Note: We do not ship equipment. This listing includes local supply and professional installation only.
🔥 Key Features
- 199,000 BTU/hr Output: Powers multiple showers and appliances simultaneously
- 10.5 GPM Max Flow: Ideal for homes with high hot water usage
- X3® Scale Prevention: No annual descaling, longer lifespan
- ENERGY STAR® Certified: High 0.95 UEF for energy savings
- Ultra-Low NOx: Meets strict emissions standards
- Flexible Venting: Up to 75 ft with 2″, 150 ft with 3″ venting
- Quiet Operation: Approx. 51 dB sound level
- Indoor or Outdoor Installation: Optional outdoor kit available
🧪 Built-In X3® Technology Advantages
Unlike standard tankless units, the ATM-199X3 uses AO Smith’s patented X3® technology to help:
- Prevent scale build-up without a separate filter or descaling kit
- Maintain high performance over time
- Reduce service costs and increase reliability
- Extend the lifespan of your tankless system
📐 Technical Specifications
| AO Smith Adapt™ SC ATM-199X3 Tankless Water Heater | |
|---|---|
| Model | ATM-199X3 |
| Fuel Type | Natural Gas (convertible to LP) |
| Input (BTU/hr) | 10,000 – 199,000 |
| Max Flow Rate | Up to 10.5 GPM |
| UEF | 0.95 (ENERGY STAR®) |
| Venting Options | 2″ or 3″ PVC/CPVC/PP, Power Direct Vent |
| Venting Length | 2″ up to 75 ft, 3″ up to 150 ft |
| Install Location | Indoor or outdoor (with kit) |
| Dimensions (H × W × D) | 40.4″ × 17.1″ × 11.9″ |
| Water Connections | ¾” NPT (hot & cold) |
| Gas Connection | ¾” NPT |
| Temperature Range | 100°F – 140°F (38°C – 60°C) |
| Sound Level | Approx. 51 dB |
| Manufacturer Warranty | Up to 15 years (heat exchanger), 5 years (parts) |
🛠️ Included Add-Ons & Upgrades
- Condensate pump and neutralizer kit (where required)
- New isolation and service valves
- System flush and cleanup of old lines (as needed)
- Warranty registration assistance
📍 Ideal Applications
- Upgrading from standard tank water heaters
- Homes with 2+ bathrooms or high usage demands
- Hard water areas seeking reduced maintenance
- New construction with limited utility space
Contact our team for a free quote and consultation to see if the AO Smith ATM-199X3 is the right fit for your home.
Specifications
Disclaimer
The price includes a standard, like-for-like installation within our service area. Some items may not be included and will be evaluated during the site visit.
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