QBY Diaphragm Pump – Troubleshooting Common Problems
Problem 1: Pump Runs But No LiquidCheck for vapor lock. The pump may be running too fast for the liquid to enter the chamber. Slow down the air supply. Also check if the suction line is blocked or if…
Problem 1: Pump Runs But No Liquid Check for vapor lock. The pump may be running too fast for the liquid to enter the chamber. Slow down the air supply. Also check if the suction line is blocked or if the inlet ball valve is stuck. Problem 2: Low Flow Possible causes include worn diaphragms, clogged ball valves, or low air pressure. Inspect the diaphragms for cracks. Clean or replace the ball valves. Verify air pressure is at least 2 Bar. Problem 3: Air Valve Freezing This happens when compressed air contains too much moisture. Install an air dryer or moisture separator. Drain the air receiver tank regularly. Problem 4: Bubbles in Discharge Air bubbles usually mean a ruptured diaphragm. Stop the pump and inspect both diaphragms. Replace if damaged. Also check that all clamps are tight. Problem 5: Liquid Leaking from Air Exhaust This is another sign of diaphragm failure. The liquid is crossing through the torn diaphragm into the air chamber. Replace the diaphragm immediately.
Quick Fix Reference
Symptom
Likely Cause
Solution
No liquid
Vapor lock, blocked suction
Slow pump, clear line
Low flow
Worn parts, low air
Replace parts, boost air
Frozen valve
Wet air
Install dryer
Bubbles
Ruptured diaphragm
Replace diaphragm
Air exhaust leak
Torn diaphragm
Replace diaphragm
Applications Summary: maintenance troubleshooting, pump repair, industrial fluid handling, chemical transfer, wastewater Thanks for visiting HAQUANPUMP. If you run into trouble with your QBY pump, our team can help diagnose and fix it. Just give us a call.
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