E238 🟡 Repair Required
Navien Error Code E238: Abnormal recirculation pump operation ● The pump is turned ON. ● Water flow is N
⚠️ The Navien tankless water heater has detected a problem with the recirculation pump and has locked out. You will not have hot water until this is resolved.
How to Fix Navien Code E238
- Step 1: Check that all valves in the recirculation loop are fully open. Sometimes a partially closed valve can restrict flow.
- Step 2: Try power cycling the Navien unit by turning it off and then back on. This can sometimes clear a temporary error.
- Step 3: If the problem persists, contact a qualified HVAC technician to diagnose and repair the issue.
What Does Navien Error Code E238 Mean?
The Navien E238 error code indicates an issue with the recirculation pump's operation. Specifically, the unit detects that the pump is running, but it's not sensing the expected water flow. This is a problem because Navien tankless units rely on proper water flow to heat water efficiently and safely. Without adequate flow, the unit can overheat, leading to potential damage or safety risks. The recirculation pump is designed to keep hot water readily available at your fixtures, and this error means that system is not working as intended.
Common Causes of Navien Code E238
- Air lock in the recirculation loop preventing proper flow.
- Recirculation pump failure (pump motor not working or impeller damaged).
- Clogged recirculation piping or strainer restricting water flow.
- Faulty flow sensor preventing accurate flow detection.
- Wiring or electrical connection issue with the recirculation pump or flow sensor.
Applicable Navien Models
Source Documentation
This error code is documented in 1 official Navien technical manual.
Navien NPF Installation & Operation ManualPage 126
ReasonAbnormal recirculation pump operation ● The pump is turned ON. ● Water flow is NOT detected.
ActionThis error occurs when the sensor on the furnace for recirculation pump operation does not operate properly. ● Turn off the furnace, turn it on again, and check if the furnace operates properly. ● If the furnace is continuously inoperable, contact Technical Support at 1-800-519-8794.
Need a Pro to Fix Navien Code E238?
A licensed HVAC technician can diagnose and fix this issue quickly.
Find a Licensed Tech Near You →Replacement Parts for Navien Tankless Water Heater Code E238
Recirculation Pump OEM: 30012413A
Flow Sensor OEM: 30010793A
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