LG Therma V fault CH14

What it means

Low flow detection during pump operation, indicating insufficient water flow through the system during circulation pump operation.

Likely causes

1. Flow sensor is electrically open
2. Water pump is in trouble/failed
3. Flow switch is electrically open
4. Flow switch contact is mechanically broken
5. Particles in water quality causing locking at the shaft of the water pump
6. Air trapped inside the unit (air not vented)
7. Strainer / water pipe clogging
8. Poor setting of external pump installation
9. Circulation pump malfunction
10. Cable interference around the flow sensor causing false switch state detection
11. Use of compressed air or oxygen for leak testing

Where to start

1. Step 3: If pressure OK, check water pump still running (vibration test at terminal box, or 'Water Pump Operating' on control panel) - if NO, investigate flow sensor (branch B)
2. Step 4: If pump running, check if control panel shows CH14 - if NO, condition is normal (END); if YES, investigate water pump trouble (branch C)
3. Touch the terminal box (black plastic box at the water pump) and feel if the water pump is vibrating