Navien NPE-180A Service Manual

Also see for NPE-180A: Installation manual Installation & operation manual Specification sheet Installation manual Operation manual

Contents

Navien NPE-180A Service Manual Manual pdf 119 page image

Version 2.21118 NPE Service Manual5.2 Troubleshooting guide by symptom5.2.1 NoiseError type Cause Check methodVibration noiseDefective installation Incorrect mounting to the wall or in an improper location.● Check for improper installation and reinstall the unit if necessary.Fan vibration noiseVibration caused due to defective blower.● Check the blower. If vibration is significant, replace the fan.● If intermittent noise occurs during operation, check the fan for debris.● If vibration noise occurs during operation of the product, and stops when the caselid is removed, check the fan.Regular noiseDefective flow sensor Rotating noise due to debris caught in the flow sensor.Malfunction of wateradjustment valveNoise due to repeated opening/closing of water adjustment valve due to a defectivePCB.Noise at ignitionGas and air differentialpressure error(Pop, Beep, Explosiveignition)1. Offset pressure adjustment error (refer to page 29)● Adjust offset pressure with the pressure adjusting screw on the main gas valve.● Set the PCB DIP 4-switch to 1-OFF,2-ON (low fire) or use the Front Panel to set theunit at "MIN.1" (refer to page 40).● If noise occurs at standard value, adjust setting above/below the standard.2. Gas supply error due to defective air pressure sensor.3. If the same error is repeated, it is due to a defective PCB.Noise duringcombustionBoiling noiseHow to check boiling:● Boiling occurs if the water temperature rises to149 °F ~167 °F(65 °C~75 °C).The heat exchanger is clogged partially due to scale deposits. Flush the main heatexchanger to remove scale.● Replace the heat exchanger if the error occurs from the start of the installation.WhirringExhaust gas that is recirculated into the water heater through the air inlet couldproduce abnormal combustion noises.● Check the distance between intake and exhaust (at least 12" (300mm)).● Check the distance between flues if two or more units are installed (at least 12"(300mm)).● Check if there are any obstructions near the flue.Low gas pressure(whirring)1. Noise occurs due to low gas pressure.● Check the gas supply pressure (dynamic pressure)2. Low gas supply due to offset pressure error. (refer to page 29)● Set the PCB DIP 4-switch to 1-OFF,2-ON (low fire) or use the Front Panel to set theunit at "MIN.1" (refer to page 40).Noise due to defective air pressure sensor.● Replace the air pressure sensor.Noise duringcombustion● Noise due to damaged air pressure hose.● Noise may be intermittent depending on the size of the damage.