Postmix Fault Finding & Troubleshooting Guide
This postmix fault finding guide helps identify and resolve common issues with bag-in-box (BIB) soft drinks systems, postmix syrup dispensers, carbonators and beverage dispensing equipment.
Use the reference guide at the bottom of our page to identify the key components of your postmix dispensing system before following the troubleshooting steps.
This Section Covers
Flat Soft Drinks Warm Soft Drinks Weak Soft Drinks Strong Soft Drinks No Syrup Dispensing No Soda Water Dispensing Gas Leak Off Taste
Flat Soft Drinks
Possible Causes & Recommended Solutions
• CO2 cylinder valve closed – Ensure the CO2 cylinder valve is fully open (13)
• Low CO2 pressure – Check the CO2 cylinder and replace if pressure is low or the cylinder is empty.(14)
• Empty CO2 cylinder – Replace the CO2 cylinder and ensure it is connected correctly.
• Warm soft drinks – Refer to the Warm Soft Drinks troubleshooting section.
Note: If the CO2 cylinder has run empty or the pressure has dropped significantly, carbonation levels within the postmix dispensing system may be affected. Once a new CO2 cylinder has been fitted, dispense several jugs of soda water to restore the correct carbonation level before serving drinks.
Warm Soft Drinks
Possible Causes & Recommended Solutions
• Postmix cooler switched off – Ensure the postmix cooler is switched on at the mains power socket.(2)
• Soda pump switched off – Check that the soda pump is switched on at the cooler.(3)
• Blocked condenser grill – Remove any obstructions and clean the condenser grill using a stiff brush to improve airflow.(4)
Note: If any of the above issues have been identified and corrected, allow up to 2–3 hours for the postmix dispensing system to return to the correct operating temperature. Soft drinks may not reach their optimum serving temperature immediately.
Weak Soft Drinks
Possible Causes & Recommended Solutions
• CO2 cylinder valve closed – Ensure the CO2 cylinder valve is fully open.(13)
• Low CO2 pressure – Check the CO2 cylinder and replace if pressure is low or the cylinder is empty.(14)
• Empty CO2 cylinder – Replace the CO2 cylinder and ensure it is connected correctly.(14)
• Empty bag-in-box (BIB) syrup – Replace the empty bag-in-box syrup.
• BIB connector not fully secured – Ensure the BIB connector is fully connected and securely fitted.(5)
• Out-of-date BIB syrup – Replace the bag-in-box syrup if it has exceeded its use-by date.
Note: If your postmix dispensing system is fitted with an automatic changeover (6), ensure both bag-in-box syrups contain product and that all BIB connectors are securely connected. An incorrectly fitted connector may prevent syrup from dispensing correctly.
Strong Soft Drinks
Possible Causes & Recommended Solutions
• Warm soft drinks – Refer to the Warm Soft Drinks troubleshooting section.
• No dispense of soda water – Refer to the No Soda Water Dispensing troubleshooting section.
• Bag-in-box (BIB) syrup connected to the wrong product line – Ensure the BIB syrup is connected to the correct product line.
Note: If the bag-in-box syrup has been connected to the wrong product line, dispense the product into a jug until the previous syrup has been fully flushed through the line and the correct flavour is dispensing consistently.
No Syrup Dispensing
Possible Causes & Recommended Solutions
• CO2 cylinder valve closed – Ensure the CO2 cylinder valve is fully open.(13)
• Low CO2 pressure – Check the CO2 cylinder and replace if pressure is low or the cylinder is empty.(14)
• Empty CO2 cylinder – Replace the CO2 cylinder and ensure it is connected correctly.(14)
• Empty bag-in-box (BIB) syrup – Replace the empty bag-in-box syrup.
• BIB connector not fully secured – Ensure the BIB connector is fully connected and securely fitted.(5)
Note: If your postmix dispensing system is fitted with an automatic changeover (6), ensure both bag-in-box syrups contain product and that all BIB connectors are securely connected. An incorrectly fitted connector may prevent syrup from dispensing from the selected product line.
No Soda Water Dispensing
Possible Causes & Recommended Solutions
• CO2 cylinder valve closed – Ensure the CO2 cylinder valve is fully open.(13)
• Low CO2 pressure – Check the CO2 cylinder and replace if pressure is low or the cylinder is empty.(14)
• Empty CO2 cylinder – Replace the CO2 cylinder and ensure it is connected correctly.(14)
• Water supply switched off – Check that the incoming water supply is turned on and the stop tap is fully open.(11)
• Carbonator timed out – Switch the carbonator off at the mains power supply and wait 30 seconds before switching it back on (1). Once the carbonator has reset, return to the dispense point and hold down the soda water button until the flow is restored.
Note: If the water supply has been switched off, the carbonator may time out. Once the water supply has been restored, follow the carbonator reset procedure above to re-establish soda water flow.
Off-Taste Drinks
Possible Causes & Recommended Solutions
• Dirty dispense nozzle (10) – Remove the dispense nozzle from the dispenser and wash thoroughly in clean warm water before refitting.
• Out-of-date bag-in-box (BIB) syrup – Replace the bag-in-box syrup if it has exceeded its use-by date.
Note: If an out-of-date bag-in-box syrup has been replaced, dispense the product into a jug until the previous syrup has been fully flushed through the line and the new syrup is dispensing correctly.
Gas Leak
Possible Causes & Recommended Solutions
• Clicking syrup pump – Check that all bag-in-box (BIB) syrups contain product and that all BIB connectors are fully connected and securely fitted (5). An empty BIB syrup or loose connector may cause the syrup pump to cycle continuously.
• Hissing or freezing CO2 cylinder – Check that the CO2 cylinder washer is present and in good condition (12). Ensure the securing nut is fully tightened and the CO2 cylinder is connected correctly.
Warning: If the CO2 cylinder is freezing or you suspect a gas leak, avoid touching the affected area directly. If the leak persists after checking the connection, turn off the CO2 cylinder and contact Platinum Beverages for assistance.
Postmix System Reference Guide
Use the reference guide below to identify the key components of your postmix dispensing system before following the troubleshooting steps.
