Condensing Tankless & Combi Systems
Navien Service & Repair in Marietta, GA
Navien's condensing tankless and combi-boiler units are efficient but produce condensate as part of normal operation, which means a clogged condensate line is one of the most common service calls we see. We handle Navien repairs and maintenance across Marietta with same-day service.
Know the Signs
Common Navien Issues We See
The unit shuts down with a condensate error. Navien's NPE and combi models route condensate through a drain line that can clog with sediment or algae over time.
The display shows a numeric error code. Navien units use specific codes for ignition, flow, and sensor faults, each pointing to a different repair.
Reduced hot water output in a combi system. Can mean the unit is struggling to balance heating and hot water demand, or scale is affecting the heat exchanger.
A burning or unusual smell during operation. Worth shutting the unit off and calling promptly — this can indicate a venting or combustion issue.
The unit cycles on and off repeatedly (short cycling). Often caused by a flow sensor issue or an oversized unit for the current demand.
How It Works
Our Process for Navien Repairs
We check the condensate line first
Since it's the single most common cause of a Navien shutdown, this gets ruled in or out immediately.
Error code diagnosis beyond the condensate line
If the issue is elsewhere, we read the specific fault code and confirm the cause before repairing.
A full system test after the repair
Confirming the unit runs cleanly through a complete heating cycle.
Common Questions
Frequently Asked Questions
Why does my Navien unit keep shutting down?
A clogged or blocked condensate drain line is the most common cause — Navien's condensing design produces acidic condensate that needs to drain freely, and sediment or algae can block that over time.
What's the difference between a Navien tankless unit and a combi system?
A standard tankless unit heats water only; a combi system also provides space heating, acting as both a water heater and part of your home's heating system.
How often does the condensate line need cleaning?
We recommend checking it annually as part of routine maintenance, more often if you've had a clog before.
Are Navien systems more complex to repair than a standard tank?
They have more components than a tank water heater, but the failure points are well understood — we service Navien units regularly across Marietta.
Have a Navien Unit That Needs Attention?
Tell us the model when you call, and we'll bring the right parts knowledge the first time. Same-day appointments, with 24-hour service for true emergencies.