Hypertherm HD3070 Plasma Arc Cutting System w/ Automatic Gas Console - Manual (Page 105)

4-16 HD3070 with Automatic Gas Console Instruction Manual
16
OPERATION
Blow Back Option to Purge Coolant Hoses
Before removing the PAC184 or PAC186 torch, the operator may want to purge the torch coolant from the coolant
hoses back into the coolant tank to minimize the coolant dripping when the torch is disconnected from the quick
disconnect. After replacing the torch, the coolant hoses should be refilled with coolant. Refer to the procedures
below.
blow back
solenoid valve
120 VAC
(Ref.)
air inlet
off-valve
assembly
Figure 4-9 Coolant Purging Setup
Purge Coolant Hoses (Blow Back)
1. Shut the power supply down at the control panel or
CNC.
2. At off-valve assembly (Fig. 4-9) connect 1/4-inch air
hose to air inlet.
3. Connect 120 VAC power cable from CNC or other
source to blow back solenoid valve.
4. Apply air at approximately 20 psi (1.4 bar) to the air inlet.
Air supply should be clean, dry and oil free in order
not to contaminate the coolant.
5. Apply 120 VAC signal for about 3 seconds to open the
solenoid valve in order to purge the coolant from the
hoses. It is not necessary to purge longer than
3 seconds.
6. After the coolant hoses have been purged, disconnect
the torch from the torch quick disconnect.
Refill Coolant Hoses
1. Reconnect torch to the torch quick disconnect.
2. Apply power to the power supply at the control panel or from CNC.
If at the power supply, depress and hold the POWER ON pushbutton switch until the COOLANT FLOW LED lights.
If at the CNC, maintain the Power On signal until the COOLANT FLOW LED lights.
When the COOLANT FLOW LED lights, release the POWER ON switch at the power supply or the Power On
signal at the CNC. The green POWER ON indicator should remain on, indicating that the system is operating
normally.
(The COOLANT FLOW LED will remain out until the coolant has pushed all of the air out of the torch cooling hoses
and the coolant returns to the tank. However, coolant hoses with too many bends can have air pockets even
though the COOLANT FLOW LED lights and the system appears ready for operation. The trapped air can cause
the torch to lose cooling momentarily and potentially cause damage to the torch.)