Tankless Water HeaterBuying Guide2025-10-26
Tankless Gas Line and Venting Requirements
Tankless units often need a larger gas line and proper stainless venting — key parts of a correct install.
Because tankless units fire at high input on demand, gas supply and venting are critical to a safe, code-compliant installation.
Gas supply
A tankless unit's high BTU demand often requires upsizing the gas line and confirming the meter and supply can handle it alongside your other appliances.
Venting and condensate
Condensing tankless units use sealed stainless or PVC venting and produce condensate that must drain properly. Correct venting is essential for safety and performance.
Key takeaways
- Tankless often needs a larger gas line
- Confirm total gas load with the meter
- Condensing units need proper venting and drainage
- Always use a licensed gas fitter
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Frequently asked questions
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