Navien Tankless Water Heater Installation
Professional Installation Across All of Long Island
Expert Navien Installation by Certified Technicians
Upgrading to a Navien tankless water heater is one of the smartest investments you can make for your Long Island home. Tankless systems deliver endless hot water on demand, take up far less space than traditional tank heaters, and can reduce your energy bills by up to 40%. At All Island Comfort, we specialize exclusively in Navien products, which means every installation we perform is backed by deep product knowledge and years of hands-on experience.
Whether you are building a new home, replacing an old tank water heater, or upgrading from an older tankless unit, our team handles everything from the initial site assessment through final system testing. We work with every Navien residential model available in the United States and will help you choose the right unit for your household size, water usage, and budget.
Why Switch to a Navien Tankless Water Heater?
Navien tankless water heaters offer significant advantages over traditional tank systems. Here is what Long Island homeowners gain when they make the switch.
Endless Hot Water
Tankless units heat water on demand, so you never run out. Multiple showers, laundry, and dishes can all run simultaneously without losing temperature.
Lower Energy Bills
Navien condensing models achieve up to 0.97 energy factor, meaning you waste almost nothing. Many homeowners see 30% to 40% reductions in water heating costs.
Space Savings
A Navien tankless unit mounts on the wall and is roughly the size of a small suitcase. Free up valuable floor space in your utility area, basement, or closet.
Longer Lifespan
While tank heaters typically last 8 to 12 years, Navien tankless water heaters are built to last 20 years or more with proper maintenance, making them a better long-term value.
Reduced Flood Risk
No storage tank means no risk of a catastrophic 40 or 50 gallon tank rupture flooding your home. Tankless units eliminate one of the most common sources of water damage.
Smart Technology
Navien units feature built-in recirculation pumps, Wi-Fi connectivity for remote monitoring, and advanced self-diagnostic systems that help prevent problems before they happen.
Our Installation Process
From the first phone call to your first hot shower, here is exactly what to expect when you work with All Island Comfort.
Free Site Assessment
We visit your home to evaluate your current setup, water usage needs, gas supply, and venting options. We measure everything and recommend the ideal Navien model for your household. You receive a detailed, written estimate with no hidden costs.
Preparation and Permits
We handle all required permits with your local municipality. If gas line upgrades or electrical work are needed, we coordinate everything so you do not have to manage multiple contractors. All work is scheduled for a single, convenient appointment.
Professional Installation
Our certified technicians remove your old unit (if applicable), run gas lines to proper specifications, install venting per manufacturer requirements, mount and connect your new Navien unit, and install a condensate neutralizer for condensing models.
Testing and Walkthrough
We test every fixture in your home for proper hot water delivery, verify gas pressure readings, check all connections for leaks, and confirm error-free operation. Before we leave, we walk you through your new system's controls, maintenance schedule, and warranty details.
Installation Services We Offer
New Construction Installation
Building a new home on Long Island? We work with builders and homeowners to integrate Navien tankless water heaters into new construction projects. Proper planning from the start means optimized gas lines, ideal unit placement, and clean venting runs.
Tank-to-Tankless Conversion
Replacing your old 40 or 50 gallon tank with a wall-mounted Navien tankless unit is our most popular service. We remove the old tank, upgrade gas lines as needed, run new venting, and install your new system in a single day.
Tankless-to-Tankless Replacement
If your current tankless water heater is aging out or underperforming, we replace it with a new Navien unit. Existing gas and venting infrastructure often carries over, making this a faster and more affordable installation.
Multi-Unit Installation
For larger homes with high hot water demand, we install multiple Navien units in a cascading configuration. This setup links two or more units together to provide seamless hot water delivery for even the most demanding households.
Gas Line Upgrades
Many older Long Island homes have 1/2-inch gas lines that are not adequate for tankless water heaters. We upgrade your gas supply line to the required 3/4-inch minimum and ensure proper BTU delivery for reliable performance.
Condensate Neutralizer Installation
All Navien condensing models produce acidic condensate that must be neutralized before entering your drain system. We install a condensate neutralizer as part of every condensing unit installation to protect your plumbing and meet code requirements.
Navien Models We Install
We install every Navien residential tankless water heater model sold in the United States. Each model is designed for specific applications and household sizes. Visit our complete Navien water heater guide for detailed comparisons.
NPE-A2 Series
Premium Condensing Tankless
Installed from $7,900
- Up to 0.97 Energy Factor
- Up to 199,900 BTU
- Up to 11.2 GPM flow rate
- Built-in recirculation pump
- NaviLink Wi-Fi control
- PVC venting (up to 60 ft)
NPE-S2 Series
High-Efficiency Condensing Tankless
Installed from $7,800
- Up to 0.96 Energy Factor
- Up to 199,900 BTU
- Up to 11.2 GPM flow rate
- Optional recirculation pump
- ComfortFlow technology
- PVC venting (up to 60 ft)
NHW-AI Series
Indoor Non-Condensing Tankless
Installed from $4,540
- Up to 0.82 Energy Factor
- Up to 199,900 BTU
- Up to 10.1 GPM flow rate
- Compact wall-mount design
- Lower upfront cost
- Stainless steel venting
NHW-AE Series
Outdoor Non-Condensing Tankless
Installed from $4,040
- Up to 0.82 Energy Factor
- Up to 199,900 BTU
- Up to 10.1 GPM flow rate
- Weatherproof outdoor housing
- No indoor venting required
- Freeze protection built in
What Is Included in Every Installation
Complete Unit Mounting
Secure wall mounting with proper clearances per Navien specifications and local building codes.
Gas Line Connection
Professional gas line connection with pressure testing and leak detection to ensure safe operation.
Venting Installation
PVC venting for condensing models or stainless steel venting for non-condensing models, installed per code.
Water Line Connection
Hot and cold water line connections with isolation valves and service ports for future maintenance access.
Electrical Connection
Dedicated 120V outlet connection for the unit's electronic controls, ignition system, and recirculation pump.
Condensate Drain and Neutralizer
For condensing models, we install proper condensate drainage with a neutralizer to protect your plumbing system.
System Configuration
Temperature settings, recirculation schedule programming, and NaviLink Wi-Fi setup (where applicable).
Full System Testing
Every fixture tested for proper hot water delivery, gas pressure verified, all connections leak-checked, and error-free startup confirmed.
Old Unit Removal
We safely disconnect and remove your old water heater (tank or tankless) and handle disposal so you do not have to.
Warranty Registration
We register your new Navien unit with the manufacturer to activate your 15-year heat exchanger, 5-year parts, and 1-year labor warranty.
Condensing vs. Non-Condensing: Which Is Right for You?
Choosing between condensing and non-condensing comes down to efficiency goals, budget, and installation requirements. Here is how they compare.
| Feature | Condensing (NPE-A2, NPE-S2) | Non-Condensing (NHW-AI, NHW-AE) |
|---|---|---|
| Energy Factor | Up to 0.97 | Up to 0.82 |
| Venting Material | PVC (lower cost) | Stainless Steel (higher cost) |
| Condensate Drain Required | Yes | No |
| Upfront Unit Cost | Higher | Lower |
| Monthly Operating Cost | Lower | Higher |
| Recirculation Pump | Built-in (NPE-A2) or optional | Not available |
| Wi-Fi Control | NaviLink compatible | Not available |
| Best For | Maximum efficiency, long-term savings | Budget-friendly, simpler install |
Tankless Water Heater Installation FAQs
How long does a Navien tankless water heater installation take?
A standard new installation typically takes 4 to 6 hours. If you are converting from a traditional tank water heater, the process may take 6 to 8 hours due to gas line modifications, new venting runs, and old tank removal. Our goal is always to complete the work in a single visit so your home has hot water by the end of the day.
Do I need to upgrade my gas line for a tankless water heater?
Possibly. Navien tankless water heaters require a minimum 3/4-inch gas supply line with adequate BTU capacity to operate properly. Many older Long Island homes have 1/2-inch gas lines that were sized for a traditional tank heater. During our free site assessment, we evaluate your gas supply and let you know upfront if an upgrade is needed before any work begins.
What is the difference between condensing and non-condensing models?
Condensing models like the NPE-A2 and NPE-S2 extract additional heat from exhaust gases before they are vented, achieving energy factors up to 0.97. They use affordable PVC venting but require a condensate drain and neutralizer. Non-condensing models like the NHW-AI and NHW-AE have a lower upfront cost and simpler installation but use more expensive stainless steel venting and are slightly less energy efficient.
How much does a Navien tankless water heater installation cost?
Installation costs vary depending on the model you choose, whether it is a new install or a tank-to-tankless conversion, and the scope of gas line and venting work required. We provide free on-site estimates with transparent, upfront pricing so there are no surprises. We also offer flexible financing through Wisetack with plans starting at 0% APR to make the investment more manageable.
What warranty comes with a Navien tankless water heater?
Navien provides a 15-year warranty on the heat exchanger, 5 years on parts, and 1 year on labor for residential installations. Professional installation by a certified technician (like our team at All Island Comfort) is required to keep the warranty valid and fully backed by the manufacturer.
Can I install a tankless water heater myself?
We strongly advise against DIY installation. Tankless water heater installation involves gas line work, proper venting to prevent carbon monoxide exposure, electrical connections, and precise system calibration. Improper installation can void your warranty, create safety hazards, and violate local building codes. A licensed, Navien-certified technician ensures the job is done safely and correctly.
What size Navien tankless water heater do I need?
The right size depends on your household's peak hot water demand and the incoming groundwater temperature. On Long Island, groundwater temperatures range from about 45 to 72 degrees depending on the season. A single Navien NPE-A2 or NPE-S2 can typically handle 2 to 3 simultaneous fixtures. For larger homes or higher demand, we can install multiple units in a cascading configuration. We size the system correctly during our free site assessment.
Will I have hot water during the installation?
Your hot water will be off during the installation process, which typically takes 4 to 8 hours depending on the project. We recommend scheduling your installation for a time when the household can manage without hot water for part of the day. Your new system will be fully operational before we leave.
Do you handle permits for the installation?
Yes. We handle all required building permits with your local municipality as part of the installation process. Long Island towns typically require permits for gas line work and water heater installations. Our team takes care of the paperwork and inspections so you do not have to.
Can a tankless water heater be installed outdoors?
Yes. The Navien NHW-AE Series is specifically designed for outdoor installation. It features a weatherproof housing and built-in freeze protection, which eliminates the need for indoor venting entirely. This is an excellent option for homes with limited interior space or difficult venting paths. Keep in mind that Long Island winters can be harsh, so proper placement and freeze protection are critical.
How do I maintain my Navien tankless water heater after installation?
Navien recommends annual maintenance that includes flushing the heat exchanger with a vinegar solution to remove mineral buildup, cleaning the inlet water filter, inspecting the venting system, and checking the condensate neutralizer media (for condensing models). Our team can set up a maintenance schedule after your installation or you can contact us whenever service is needed. Regular maintenance extends the life of your unit and keeps it running at peak efficiency.
What happens to my old water heater?
We remove and dispose of your old water heater as part of the installation. Whether you have a traditional tank or an older tankless unit, we safely disconnect it, drain it, and haul it away. The cost of removal is included in your installation quote.
Ready to Go Tankless?
Get a free, no-obligation estimate for your Navien tankless water heater installation. Our certified technicians serve all of Nassau and Suffolk County and are available 24/7. Check our coupons page for current specials, and ask about flexible financing options starting at 0% APR.
Have questions? Check our FAQ page for answers about Navien installation, maintenance, and more.