Nearly 17% of a household's total energy consumption goes directly toward heating water. If cold showers, inflated utility bills, or a bulky traditional tank are wearing you down, a tankless water heater could be the upgrade that changes everything. This guide walks you through every phase of the process — sizing, placement, installation, and ongoing maintenance — with real data and practical insights.
Pre-Installation Checklist
1. Assess Your Household Demand
Start by calculating your total flow rate. A standard shower draws approximately 2.5 GPM, while a dishwasher typically uses around 1.5 GPM. Add up every fixture that could run simultaneously at peak hours — that's your minimum unit capacity. For temperature rise, subtract your groundwater temperature from your target output temperature (typically 120°F). Getting this math right is non-negotiable: undersized units drive up energy use by as much as 25%.
2. Choose the Right Location
For gas units, NFPA 54 requires a minimum of 12 inches of clearance from any combustible material. Placement is also a performance factor — the closer the unit sits to your most-used faucets, the less heat is lost in transit and the less water is wasted waiting for warmth. One homeowner in Seattle reportedly saved $200 per year simply by relocating their unit closer to the primary fixtures.
Tools & Materials
Gather everything before you start. Stopping mid-installation to source a part is one of the most common causes of errors and delays.
Opt for flexible gas connectors rather than rigid pipe wherever possible. They allow for minor alignment adjustments during mounting without having to rework your gas line routing — a small choice that saves significant frustration.
Step-by-Step Installation
Shut Off Utilities
Turn off both your gas supply and water main before touching anything. Once shut off, test gas lines thoroughly using a soap solution — bubbles reveal leaks that could be hazardous during operation.
Mount the Unit
Use the manufacturer's provided template for precise screw placement. Deviating from the template might seem harmless, but data from Rheem shows that 90% of warranty voids are tied directly to incorrect mounting practices.
Connect Plumbing & Gas
Use dielectric unions on all water connections to block corrosion at the joint. For gas lines, consider CSST tubing — one Texas installer reported a 30% reduction in callbacks after making the switch from traditional black pipe.
Electrical & Gas Requirements
Matching your unit to the correct supply specifications is critical. Running a gas unit on insufficient pressure is the leading cause of ignition failure — responsible for 60% of all reported issues according to the AGA.
| Unit Type | Required Voltage | Gas Pressure |
|---|---|---|
| Electric | 240V Dedicated Circuit | N/A |
| Gas (LP or Natural) | 120V | 5–10" WC |
Maintenance Tips
Tankless systems are designed for longevity, but they require periodic attention to reach their full lifespan potential.
- Descale annually — this single maintenance task can extend the operational lifespan of your unit by 5 to 7 years by preventing mineral buildup in the heat exchanger.
- Install a sediment filter upstream of the unit to intercept debris before it reaches internal components, reducing the frequency and cost of maintenance visits.
- Inspect your venting system each season to ensure there are no blockages or damage. Improper venting is the leading cause of CO-related hazards in gas units.
Key Takeaways
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1
Size correctly from the start. An undersized unit doesn't just struggle — it actively increases your energy consumption by up to 25% trying to keep up with demand it wasn't built to handle.
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2
Venting is your top safety priority. Improper ventilation is the single greatest cause of carbon monoxide hazards in gas-powered tankless installations. Never cut corners here.
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3
Professional installation is often worth it. Industry data shows 78% of DIY installations require professional corrections. A certified installer the first time can cost less than fixing a DIY install the second time.
Ready to Upgrade?
Explore a top-rated outdoor liquid propane tankless water heater — designed for performance, built for reliability, and ready for your backyard setup.
Eccotemp 7.0 GPM LP Heater