Schreiber Chillers Excellon 150EX - Manual (Page 15)

Excellon 235785-01/02
1. Rotation of the water pump and fan motor must be correct.
2. Water in the tank must be at the proper level.
3. High temperature thermostat is set at 90 degrees F, as requested by Excellon.
4. All doors on the chiller must be in place.
This Unit is not weatherproof and should not be installed outdoors. Check with the
factory about outdoor usage.
SPECIAL INSTRUCTIONS
WATER PUMP
The manual switch for off and on operations controls the water pump. The motor on this
pump has a built-in overload protection, as do all the motors in our system.
ELECTRICAL CONTROLS - Control Circuit 24 Volts
The control circuit for the refrigeration system has several controls wired in series. First
are the high and low pressure switches that are mounted in the control panel.
High Pressure Switch - The high-pressure switch will shut off the refrigeration system
in the event the refrigerant pressure is too high. High pressure can be caused by the
condenser becoming restricted, by foreign material on the outside surface of the
condenser, or if the fan motor is not running. If the high-pressure limit switch should cut
out, there is a manual reset switch, which is located at the control panel on the right
side. In order to reset this switch, the disconnect switch and the switch must be turned
off and the control panel door must be open. If and when the high-pressure switch is off,
check the "Trouble Shooting" chart for diagnosis.
Low Pressure Switch - The low pressure switch will cut out at any time the refrigerant
pressure in the refrigeration system is below 25 psi. Low psi can be caused by a freeze
up in the water tank, a leak in the refrigeration system, if the system is low on Freon (R-
22), or if there is any sort of restriction in the system. If the switch cuts out, it will
automatically reset. Never try to adjust the high and low pressure switches or by-
pass them, or serious damage to the system will result. Adjustment should only be
made after the internal pressure of the refrigeration system has been read.
Please read the enclosed instructions on the ambient air temperature controller. The off
and on cycle of the refrigeration system is controlled by the ambient air. Should the unit
be cycled off by the ambient air controller, or if you need to have the refrigeration to
come on and bypass the ambient air controller, put a cup of cold water on the ambient
air probe. The second control of the circuit is the ambient air temperature controller. It
controls the cycling of the refrigeration system. Once this control is set, it will control the
cycling of the unit automatically. Do not set it below freezing unless the proper amount
of antifreeze is put into the unit. Because the antifreeze is a poor conductor of heat,
never add more than necessary.