Yuanyin Machinery Pneumatic Pump Series Benchtop Post-Mix Cola Machine Official User Manual
All contents of this manual are the sole official standards for equipment installation, operation, and maintenance. The company assumes no responsibility for equipment damage or safety accidents caused by failure to follow this manual, and such actions will affect the equipment warranty rights.
Chapter 1 Important Safety Instructions
1.1 General Safety Specifications
CO₂ cylinders are high-pressure vessels. Only nationally certified food-grade commercial CO₂ cylinders must be used. Expired, uninspected, damaged cylinders, or industrial-grade CO₂ are strictly prohibited.
Cylinders must be stored upright and fixed, away from heat sources, open flames, direct sunlight. Ambient temperature must not exceed 45°C. Cylinders must not be tipped, impacted, or exposed to sunlight.
All hoses and connections must use original factory standard accessories. Non-original seals, gaskets, connectors are prohibited. Unauthorized modification of air, water, or syrup lines is prohibited. Operating above rated pressure is prohibited.
Before cleaning, maintenance, or troubleshooting, always close the main cylinder valve, release residual pressure in the lines, then proceed. Do not disassemble under pressure.
Installation area must be well-ventilated. If CO₂ leakage occurs, immediately close the cylinder valve, retighten / check for leaks.
Equipment is for commercial use only. Operators must be familiar with this manual. Minors and non-professionals are prohibited from operating, disassembling, or handling the equipment or cylinders.
1.2 Pneumatic Pump Version Specific Safety Requirements
Before syrup priming and operation, a 15-minute air tightness pressure-hold test must be completed. The equipment may only be used after passing the test. Operation with leakage hazard is prohibited.
Do not over-adjust pressure gauges. Low-pressure gauge must not exceed 60 psi; high-pressure gauge must not exceed 100 psi. Over-pressure operation will cause hose burst or pump damage.
If the pneumatic pump stalls, makes abnormal noise, or fails to exhaust, immediately close the cylinder valve, release line pressure, then troubleshoot. Do not repeatedly press the valve head forcibly.
Before replacing the cylinder or disassembling gauges, ensure the cylinder valve is fully closed and there is no residual pressure in the lines. Do not disassemble under pressure.
Chapter 2 Product Overview and Core Technical Parameters
2.1 Product Introduction
This series of pneumatic pump commercial carbonated beverage machines is a pure pneumatic drive commercial beverage equipment independently developed by Xiamen YuanYin. No electric syrup pump is needed. It relies on CO₂ cylinder pressure to drive pneumatic pump sets for accurate syrup delivery, compatible with multi-flavor bag-in-box syrup. The equipment has stable structure and low failure rate, widely used in catering stores, convenience stores, mobile stalls,自助 restaurants, especially where power supply is limited.
2.2 Core Technical Parameters
Drive mode: Pure pneumatic drive (CO₂ cylinder pressure), no electric syrup pump, three-pump set driven by air pressure
Compatible cylinder specification: Commercial food-grade CO₂ cylinder; industrial-grade CO₂ prohibited
High-pressure gauge working range: 70–100 psi; maximum pressure must not exceed 100 psi
Low-pressure gauge working range: 40–60 psi; factory recommended setting 40 psi
Water tank capacity: Standard 30L food-grade stainless steel water tank; fill to level parallel with tank top
Syrup lines: 3 lines (standard), corresponding to 3 pneumatic pumps and 3 valve heads
Water supply mode: Tap water connection; standard with 4-to-3 adapter, 1.5m independent water inlet hose, pre-filter
Air tightness pressure-hold test duration: 15 minutes; after closing cylinder needle valve, no pressure drop on gauges = pass
Drainage method: Built-in drain directs to drip tray; no external drain connection needed
2.3 Machine Structure Description
Main unit core: 30L stainless steel water tank, 3 food-grade pneumatic syrup pumps, valve head assembly, drip tray
Air circuit components: High-pressure gauge, low-pressure gauge, food-grade air hoses, eye gaskets
Water circuit components: Pre-filter, 4-to-3 adapter, independent 1.5m water inlet hose, water inlet port, built-in drain port
Syrup components: Syrup quick-connect valve, food-grade syrup tubes
Included tools: Cylinder wrench, filter wrench, small screwdriver, hanger plate + screws, spare sealing gaskets
Chapter 3 Unboxing Inspection and Parts Check
3.1 Unboxing Operation
The equipment outer packaging is a wooden crate. When opening, pry off the fixing boards; do not disassemble violently to avoid damaging the main unit, gauges, etc. After opening, first inspect the main unit exterior for any bumps or deformation during transport, then remove all loose parts and documents from inside the crate and drip tray.
3.2 Parts List Check
Take the packing list from the drip tray, check each standard accessory item by item to confirm no missing, deformation, or damage. After checking, sign the packing list receipt. If any part is missing or damaged, do not start the equipment; contact YuanYin after-sales department immediately for replacement.
Main unit & core components: Main unit (with 3 pneumatic pumps), drip tray, drip tray hanger, high/low pressure gauge assembly, sealing accessories
Hoses & sealing accessories: Food-grade water inlet hose, food-grade air hose, food-grade syrup tubes, 4-to-3 adapter, water inlet filter (with cartridge and two connectors), eye gaskets (10–15 pcs), primary/spare sealing gaskets
Special tools: Cylinder wrench, filter wrench, small screwdriver, hanger plate screws
Quick-connect components: Syrup quick-connect valve, hanger plate
Documents: Product certificate, this user manual
Chapter 4 Standardized Installation Procedure
4.1 Pre-installation Preparation
Installation environment confirmation: Place equipment on a flat, hard surface. Install a 4-point water inlet ball valve nearby; distance between water source and equipment ≤2m. Keep away from heat, open flames, direct sunlight. Reserve sufficient space for upright cylinder fixation and flat syrup bag placement.
Tool preparation: Confirm all original factory standard tools are available; no extra non-standard tools needed for full installation.
4.2 Unboxing and Parts Inventory (Step 1)
Unbox as per 3.1, check parts against packing list item by item to ensure no missing or damaged parts. After inventory, sign the packing list. Do not proceed with installation if any part is missing.
4.3 Air Circuit Installation and Sealing Specification (Step 2)
4.3.1 High-Pressure Gauge Installation
Tear off cylinder seal, take out high-pressure gauge accessories and cylinder wrench.
Insert sealing gasket into threaded port at bottom of high-pressure gauge; hand-tighten to limit.
Use cylinder wrench for final tightening, ensuring gauge body is vertically downward without tilt, to avoid seal failure.
4.3.2 Low-Pressure Gauge Installation
Take 1 eye gasket, ensure large opening outward, place at tee connector.
Use 14mm wrench or adjustable wrench; hand-tighten tee connector first, then tighten firmly.
Connect the tail air hose end similarly. Both ends of a single air hose need eye gaskets; align vertically before tightening.
Connect the other end of high-pressure gauge with same process; steady gauge body to avoid tilting that could cause loosening or thread stripping.
4.3.3 Air Tightness Verification (Mandatory Test)
After completing pressure adjustment of the whole machine, close the cylinder needle valve.
Hold pressure for 15 minutes. Observe whether pointers on both low-pressure and high-pressure gauges drop.
If pointers drop, check two core issues: (1) gasket not tightened or wrong orientation; (2) thread stripping. After correction, repeat the pressure-hold test until passing.
Red line: If air tightness test fails, do NOT proceed to water or syrup line installation.
4.4 Water Circuit and Filtration System Assembly (Step 3)
4.4.1 Filter Installation
Use 4-to-3 adapter and 1.5m independent water hose to connect to the on-site 4-point ball valve. Confirm the built-in gasket at the connector is in place to avoid leakage.
Regardless of factory condition, you MUST remove the protective film from the filter cartridge surface.
Rinse the cartridge with clean water, then install it upside down back into the filter housing.
Hand-tighten the filter cover first, then use the dedicated filter wrench to moderately tighten. Do not over-tighten to avoid thread stripping.
4.4.2 Water Inlet Connection
Connect one end of the 1.5m independent water hose to the angle valve, and the other end to the inlet marked with an “arrow →” on the filter (strictly follow water flow direction; reverse connection prohibited).
Connect the other end to the water inlet port on the back of the machine.
If leakage occurs after water is turned on, determine that the connector is not tightened enough. Turn off water source, retighten connector, replace sealing gasket.
4.4.3 Initial Water Filling (Prerequisite)
Pour 30L of clean water through the water filling port.
Fill to the scale line on the cylindrical stainless steel water tank (parallel to tank top) and stop.
This equipment does not require an external drain; it has a built-in drain port that directs wastewater to the drip tray, no extra container needed.
4.5 Syrup Lines and Pneumatic Pump Set Connection (Step 4)
4.5.1 Pneumatic Syrup Pump Connection
3 syrup tubes have no fixed connection order; they can correspond to any of the 3 pneumatic pumps.
Insert each syrup tube forcefully into the pump connector until a “click” sound is heard, confirming the latch is fully engaged.
After connection, reset and lock the latch to prevent accidental disconnection during operation.
4.5.2 Syrup Bag Connection
Wipe the tail end of the syrup tube with a clean cloth to ensure no dirt or impurities.
Vertically insert the syrup tube tail into the syrup quick-connect base until it bottoms out.
Take the syrup bag, place the “A” side downward, tear open the carton along the dotted line.
Remove the quick-connect cap, align and screw onto the quick connector, then lock.
Repeat the same steps for the other two syrup bags. Ensure all connections are tight with no leakage.
4.6 Pressure Adjustment and Syrup Priming (Step 5)
4.6.1 Pressure Gauge Adjustment
Locate the low-pressure gauge adjustment rod, turn clockwise three full turns.
Adjust low-pressure output to stabilize within 40–60 psi. Factory recommended target is 40 psi.
Simultaneously confirm high-pressure gauge is stable within 70–100 psi. If out of range, readjust cylinder output pressure.
4.6.2 Syrup Priming Operation
Core requirement: 30L water filling AND 15-minute air tightness pressure-hold test must both be passed before starting syrup priming.
After pressure setting, start priming process.
Operate the dispensing valve repeatedly until the pneumatic pump stops exhausting – this indicates the syrup line is fully primed.
Perform the above priming process for all three pumps simultaneously to ensure each syrup line is full with no air residue.
Chapter 5 Daily Operation Specifications
5.1 Power On/Off Procedure
Startup: Check water supply normal → open water source ball valve → slowly open main cylinder valve → confirm gauge readings within rated range → press valve head to exhaust and confirm normal → ready to dispense.
Shutdown: Close main cylinder valve → press valve head to release residual pressure → close water source ball valve → for long-term shutdown, drain water and syrup from tank and lines, clean interior.
5.2 Beverage Dispensing Operation
Before dispensing, press valve head for 1–2 seconds to confirm no air residue in lines and normal syrup/water mix.
When dispensing, hold cup tightly against valve head outlet, press valve head to the bottom; release to stop flow.
Do not press valve head empty for extended periods to avoid rapid gas loss and pneumatic pump dry running wear.
5.3 Flavor and Pressure Adjustment
Sweetness adjustment: Use the syrup valve fine adjustment knob – counterclockwise reduces syrup output, clockwise increases. Taste test after adjustment.
Carbonation adjustment: Adjust pressure via low-pressure gauge rod. Higher pressure gives stronger carbonation. Do not exceed 60 psi. Daily use recommended at factory setting of 40 psi.
Chapter 6 Daily Maintenance and Cleaning
6.1 Daily Maintenance Cleaning
After closing, close main cylinder valve and water source ball valve, release residual pressure. Wipe exterior, valve heads, drip tray with warm water. Empty drip tray daily to prevent bacteria.
Check cylinder pressure is within normal range, syrup bag remaining quantity sufficient, all connections have no water, syrup, or air leaks.
Rinse valve head outlet with clean warm water to avoid syrup residue drying and clogging valve or pump.
6.2 Weekly Maintenance
Remove drip tray and valve head flow guides; wash with food-grade neutral detergent, rinse with clean water, dry, and reinstall. Do not use strong acids/alkalis or abrasive cleaners.
Check filter cartridge condition. If water flow slows, clogging, yellowing, or odor occurs, replace cartridge. Normal replacement cycle: 3–5 months.
Inspect all air, water, syrup hoses for aging, cracking, kinking. Tighten loose connections, replace aged sealing gaskets.
Perform a simple pressure-hold test on the air circuit to confirm no slow leakage.
6.3 Monthly / Quarterly Deep Maintenance
Perform circulation disinfection cleaning of water and syrup circuits using food-grade equipment cleaner. After circulation, rinse repeatedly with clean water to avoid residue, preventing pump clogging.
Disassemble pneumatic pump quick-connect interfaces, check inside for dried syrup or clogs, clean with warm water, reassemble to ensure smooth pump action.
Conduct comprehensive air tightness re-check on high/low pressure gauges and regulators; replace aged hoses and gaskets.
Clean all internal hoses and water tank, remove scale and impurities to ensure water flow.
6.4 Long-term Shutdown Maintenance
If equipment is out of service for more than 7 days, close cylinder valve, remove cylinder for separate storage, drain all water and syrup from tank and lines, thoroughly clean and disinfect interior, pumps, valve heads.
Close water source. Store equipment in dry, ventilated environment, no direct sunlight, no corrosive gases.
Before reusing, repeat air tightness pressure-hold test per installation manual, replace filter cartridge, disinfect and flush water circuit. Only use after confirming normal.
Chapter 7 Common Troubleshooting
Symptom: No pressure rise / continuous pressure drop
Core checks: Cylinder valve not open, cylinder empty, air connection leaks, gasket orientation wrong
Quick fix: Fully open cylinder valve, check cylinder remaining. Repeat 15-minute pressure-hold test, locate leaks, retighten connections, replace eye gaskets (large opening outward)
Symptom: Pneumatic pump not working / no syrup output
Core checks: Insufficient pressure, syrup line clogged, quick-connect not locked, syrup bag wrong orientation, air in pump
Quick fix: Check low-pressure gauge within 40–60 psi. Retighten syrup quick-connect, place bag “A” side down flat. Repeatedly press dispensing valve to exhaust until syrup flows normally.
Symptom: Syrup output intermittent / with bubbles
Core checks: Air in syrup line, low syrup bag, connection leaks, pump stuck
Quick fix: Replace syrup bag, press valve head repeatedly to purge air. Check all connections tight. Disassemble and clean dried syrup inside pump.
Symptom: Air only, no water
Core checks: Water supply interrupted, inlet ball valve closed, filter clogged, water hose reversed
Quick fix: Check water supply, fully open inlet ball valve. Replace filter cartridge. Confirm filter inlet/outlet connected according to water flow direction.
Symptom: Equipment water leakage
Core checks: Connector not tightened, sealing gasket aged or missing, filter bowl not tightened
Quick fix: Turn off water source, retighten all leaking connections, replace aged/missing gaskets, retighten filter bowl.
Symptom: No carbonation / few bubbles
Core checks: Low pressure, cylinder empty, air leak, high water temperature
Quick fix: Check cylinder remaining, adjust pressure to rated range, repeat air tightness test. Confirm water temperature normal; in summer, increase pre-cooling time.
If above methods do not solve the problem, do not disassemble the machine yourself. Contact YuanYin after-sales technical service immediately for professional assistance.
Chapter 8 Warranty Service Terms
8.1 Warranty Period
Whole machine warranty: 12 months. Core component (compressor) warranty: 36 months, calculated from the date of equipment receipt. During warranty, non-artificial damage or quality issues are covered by free repair or replacement.
8.2 Disclaimer (Warranty becomes void in following cases)
Failure to follow this manual, including but not limited to over-pressure operation, using equipment without air tightness test, unauthorized modification of lines, use of non-original parts.
Artificial violent damage, improper cylinder use, transport damage, accident/disaster damage.
Failure to perform daily maintenance as required, causing pump clogging, hose corrosion, part aging.
Use of industrial-grade CO₂, non-food-grade syrup, unqualified water source causing damage or contamination.
Unauthorized disassembly, repair, or replacement of parts without company approval.
8.3 After-Sales Service Contact
National after-sales hotline: 19859229180 / 18751665457 / 18659225470
Company address: 5th Floor, South Side of Building No.2, 687 Ji’an Road, Tong’an District, Xiamen City, Fujian Province, China