Airless spray, unlike the conventional spray method, does not use air. Hydraulic pressure is applied until the fluid atomizes. A good example of this is a garden hose. Although water needs little pressure to atomize, roof coatings typically need about 2000psi to atomize.
Start-Up
1. Connect suction hose, spray hoses, gun and tip. 2. Ground pump. 3. Put suction kit in material. 4. Open prime valve. 5. Open bypass valve. 6. Lower pressure. 7. Choke on. 8. Start engine. 9. Choke off. 10.Close bypass valve. 11.Close priming valve.
Adjust Pressure
1. Lower pressure until fan has tails. 2. Raise pressure until tails disappear. 3. Note setting on dial or gauge.
Clean-Up
1. Put suction kit into water or solvent. 2. Remove spray head. 3. Prime pump. 4. Flush system. 5. Replace spray head and clean. 6. If water clean-up, prime with non-corrosive agent such as anti-freeze.
Math
Tip selection: 1gal/square = .031 tip = 1 gal/minimum 2 gal/square = .045 tip = 2gal/minimum Average pressure loss in hose is 4psi per foot. Approximate pressure loss due to vertical is .25psi per foot.
Volume of hoses per 50 foot length: 3/8” = 0.3 gal ½” = 0.5 gal ¾” = 1.25 gal 1” = 2.25 gal Delivery of spray tips: 0.021 = 0.5gpm 0.031 = 1gpm 0.045 = 2gpm 0.055 = 3gpm
1kw band heater = 10 degree rise per hour per 55 gal 2kw band heater = 15 degree rise at 2 gal per minute 4kw band heater = 30 degree rise at 2 gal per minute
Safety First
→ This equipment develops very high pressures that can cause injection injury. → Airless spray generates static electricity that can cause sparks. Use static grounded hose and ground the pump. → This equipment has moving parts that can injure fingers.
