F-1031, Section 2119
Page 12 of 24
NOTE: For an explanation of the Control Air Circuit function, see Page 16.
The Eclipse
ES Air Control circuit is preset and adjusted
at the factory prior to shipment. In most cases, the factory
settings will provide satisfactory performance for typical
CAFS and auxiliary air applications. The FIXED air opera-
tion is factory set at 145-150 P.S.I.G. The AUTO air oper-
ation is set (or trimmed) to match the fire pump discharge
pressure (+/- 5%).
If the air control circuit requires changing or the circuit has
lost its factory setting, the following procedure can be
used to “fine tune” the system.
1. Preset the Air Inlet Trim Valve (AITV) by closing
the valve, then opening the valve three turns.
2. Preset the Balance Trim Valve (BTV) to full open.
3. Start the fire pump, remaining at idle speed, and
establish water flow either through a discharge or
tank recirculation.
4. Set the Auto Sync Control Panel to UNLOAD
mode and close all discharges.
5. Start the air compressor by placing the compres-
sor engage switch to “ON”.
6. Read the main air pressure gauge (should read
40-50 P.S.I.G.). In the UNLOAD mode, this mini-
mum pressure is always present to provide com-
pressor oil circulation.
Final Adjustments for the FIXED and AUTO
Modes
FIXED Air Mode
1. Locate the Fixed Pressure Regulator. Note that
the regulator has an adjustment screw with a lock
nut.
2. Loosen t
he regulator’s lock nut.
3. Place the controls to FIXED position on the Auto
Sync Panel. The compressor will build pressure
to some value and hold (regulate).
4. Adjust the screw on the Fixed Pressure Regula-
tor, while monitoring the air pressure gauge, until
the desired pressure is reached. Turning the
screw in will INCREASE the pressure. Turning the
screw out will DECREASE the pressure.
5. Tighten down the locknut once the desired regu-
lated pressure is achieved.
6. Verify the fixed regulator is performing by varying
the compressor speed and monitoring the air
pressure gauge. The pressure should remain
steady at the fixed pressure setting.
With the final adjustments to the FIXED air mode com-
plete, proceed with setting the AUTO air mode.
AUTO Air Mode
1. Place the Auto Sync controls to the AUTO posi-
tion with the fire pump operating at 100 P.S.I.G.
main discharge and minimal flow.
2. Monitor main water discharge pressure gauge
and the air pressure gauge. The pressure read-
ings should be the same. If not, go to Step 3.
Air Inlet Trim Valve (AITV)
3. Close the trim valve in half turn increments if the
air pressure is too high. Monitor both water and
air pressure gauges until the pressures match.
Once the pressures match, no further adjust-
ments are needed and go to Step 5. If the air pres-
sure is too low, open the trim valve a half turn then
check water and air pressure gauges. If the air
pressure is still too low, open the trim valve a half
turn. If the air pressures match, no further adjust-
ments are needed and go to Step 5. However, if
you air pressure is still too low, go to Step 4.
Note that the Air Inlet Trim Valve is now four turns open
from fully closed. It is not desirable to have the trim valve
open more than four turns. To extend the trim valve’s
range, use the Balance Trim Valve (BTV).
4. Close the BTV one turn from the fully open posi-
tion. Check the water and air pressure gauges. If
the air is still too low, again close the BTV one turn
and check the gauges. Keep repeating the pro-
cess until the air pressure matches or is slightly
higher than the water pressure. The final adjust-
ment can be done using the AITV and Step 3.
5. Verify the balance valve is performing by varying
the fire pump discharge pressure and monitoring
the water and air pressure gauges. The air pres-
sure should follow and match the water pressure.
If not, repeat the final adjustment procedure.
Calibration - Control Air Circuit
Air Inlet Trim Valve / Balance Trim
Valve
Air Inlet Trim Valve (AITV)
Balance Trim Valve (BTV)
Fixed Pressure
Regulator
