Navien Tankless Water Heaters
Certified Navien installer and service technician. New installations and repairs throughout Southern California.
Why Go Tankless?
Endless Hot Water
A tankless unit heats water on demand. You never run out, no matter how many people are showering.
20+ Year Lifespan
A quality tankless unit with annual maintenance will outlast 2–3 tank water heaters. Long-term it wins on cost.
Energy Savings
You're not keeping 50 gallons hot 24/7. You heat only what you use — typically 20–30% more efficient than a tank unit.
Condensing — The NPE Family
Condensing tankless. Higher efficiency (up to 0.96 UEF), 2" PVC venting up to 75 ft, indoor or outdoor mounting. The right pick for most SoCal homes — Navien splits the line into two tiers: A2 (premium, built-in recirculation) and S2 (standard, no built-in recirc but the same condensing efficiency).
NPE-A2 — Premium with built-in ComfortFlow®
The A2 ships with a built-in recirculation pump and a 0.5-gal internal buffer tank. Kills the "cold-water sandwich" that plagues bare tankless installs. Cascade-capable up to 32 units for restaurants or large homes.
NPE-S2 — Standard, no built-in recirc
Same 0.96 UEF condensing core as the A2 but without the built-in recirc pump or buffer tank. Right call when the home already has a dedicated return line, when recirc isn't needed, or when the budget pushes back. Four sizes including a 150,000-BTU entry-level not offered in A2.
Non-Condensing — The NPN Family
Non-condensing tankless. 0.81 UEF, no condensate drain to run, stainless steel heat exchanger, single-pipe 3"×5" concentric vent. Right pick when an NPE install would mean fighting a condensate drain run, replacing existing B-vent, or when budget is the deciding factor. Navien splits the non-condensing line into NPN-U (indoor or outdoor) and NPN-E (outdoor only).
NPN-U — Indoor or Outdoor
Navien's universal non-condensing line — the only non-condensing model rated for either indoor or outdoor mounting. Easy retrofit when the existing setup doesn't support a condensate drain.
NPN-E — Outdoor Only
Outdoor-only sibling to the NPN-U. Same non-condensing core, but rated for exterior wall mounting only — which keeps the install simple in SoCal's non-freezing climate (no indoor vent run, no condensate run, no combustion air sourcing). Also approved for manufactured / mobile homes where NPE condensing units typically aren't.
Quick pick logic: Going outside, no freeze risk, simplest install? NPN-E. Need indoor mounting OR want the flexibility either way? NPN-U. Want long-term efficiency savings + recirc + future-proofing? NPE-A2 or S2.
Installation Requirements
Switching from a tank unit isn't always plug-and-play. Here's what may need to change:
Gas Line
Navien supports up to 25 ft on a 1/2" gas line. Beyond that, or in older homes with longer runs, a 3/4" line is required. We assess your existing setup during the quote visit and include any needed upsizing in the estimate.
Venting
2" PVC for a single unit. Multi-unit installations require larger pipe. Direct vent (two pipes) or power vent. Existing B-vent from a tank unit cannot be reused — new PVC runs required.
Condensate Drain
Condensing units produce acidic condensate that needs to drain. We run a line to the nearest floor drain, utility sink, or condensate pump.
Electrical
120V/60Hz required for the control board. Standard outlet near the installation location — not a dedicated circuit in most cases.
Water Quality (IE specific)
Inland Empire water is hard — high mineral content. We always recommend a pre-filter and annual descaling. Ignoring this shortens heat exchanger life significantly.
Annual Maintenance — Don't Skip It
IE water is hard. Calcium and magnesium deposit on the heat exchanger surfaces over time — this reduces efficiency, causes banging sounds, and eventually causes the heat exchangers to fail prematurely. Annual flushing with a descaling solution takes about an hour and protects a $2,000+ investment.
Navien Experts in SoCal
Installation, service, and error code diagnostics. Call or schedule online.