
AGF Manufacturing Inc. • Phone: 610-240-4900 • Fax: 610-240-4906 • www.agfmfg.com 7
OPERATING INSTRUCTIONS
The M5500 is equipped a Programmable Logic Controller (PLC) which monitors
the status of the unit, controls the drain cycle, and provides feedback based on
input it receives from the level switch, thermostat, and motorized ball valves. The
PLC offers the ability to conduct automatic draining of the condensate when it is
full or on demand draining at any time.
The system uses a oat-style level switch to monitor the amount of condensate
collected. When enough condensate has accumulated, the level switch is
activated. This informs the PLC which triggers the alarm to sound and pulse the
red light mounted on the M5500 electrical enclosure. If the M5500 is in automatic
drain mode (indicated by the auto lamp being on) the system will automatically
step through a drain cycle. If the M5500 is not in automatic drain mode (on demand
mode), the alarm will activate as before, but the drain cycle will not start until the
local drain button is pressed or, if it has been wired, the remote button is pressed.
While the alarm is active, an auxiliary contact is also triggered and is capable
of being wired back to a central control panel for remote indication. The alarm
and auxiliary contact are automatically reset when the drain cycle is successfully
completed, and the condensate level is drained below the switch.
Based on the setting of the thermostat, the PLC will activate a 150W heater. The
factory default setting of 50º F is suitable for conditions down to 0º F. Consult with
AGF for recommended settings if operating the M5500 in an area below 0º F. The
thermostat controls the heater operation to within approximately ±10º F of the
set-point (i.e. S.P. 50º F, on @ 40º F, off @ 60º F).
NOTE: AGF does not recommend setting the thermostat below 50º F.
In addition, if the thermostat calls for the heater to be continuously on for two
hours, the PLC will activate the alarm and auxiliary contact as before, and single
ash the power lamp. This is to notify the operator that there is an issue with
maintaining the desired temperature which could be a result of the cabinet door
being left open or the heater not keeping up with temperature demand.