Air Source Heat Pump Water Heater
16
Fluoride
injection mouth
Screwdriver
Fluid pipe
Fluid valve
Hex key
Air pipe
Air valve
Figure 7-3 Opening the fluid valve and air valve
Pressure gauge
-76cmHg
Low pressure
valve opened
High
pressure
valve
closed
Hoses filled
Fluid valve
Air valve
Vacuum
pump
Figure 7-4 Vacuum pump connection diagram
(2) Vacuum pump:
1) Connect the filling hose to the fluoride injection mouth of the air valve.
Ensure that the valve cores of the air valve and fluid valve are tightly
closed.
2) Connect the joint of the filling hose to the vacuum pump, as shown in
Figure 7-4.
3) Fully open the low pressure valve of the pressure gauge.
4) Start the vacuum pump to vacuumize the air for 20 minutes or more, and
ensure that the pressure gauge pointer points to -1.0 x 105 Pa (-76cmHg).
Close the low pressure valve, and stop running the vacuum pump. Wait 2
minutes. If the number indicated by the pressure gauge pointer does not
rise, the vacuumization and piping are successful. If the number indicated
by the pressure gauge pointer rises, it indicates that air is entering the
system. In this case, check the piping for leaks, and vaccumize the air
