Steffes 612EXT Owner & Installers Manual - Manual (Page 7)

C. CONTROL DEVICES/SAFETY LIMIT DEVICES
Table 2
CATEGORY DEVICE NAME ACTION
Control Devices: Charge Control Thermostat/Switches Cycles charging elements to maintain a
proper core charge level.
Room Temperature Thermostat Cycles unit fan(s) to maintain space temperature.
Bimetallic Coil and Damper Assembly Modulates damper to maintain a preset
discharge temperature.
Charge Control Sequencer/Relay Stages elements "ON" to reduce load on
charge control thermostat.
(Used only on models 412, 512 & 612)
Charge Indicator Light Indicates heating elements are being energized.
(If unit is equipped.)
Time Clock -- Seven day programmable Monitors time and signals heating elements to charge
with Battery Back-Up during off-peak hours. Typically used in Time-of-Use
(Optional in EXT series only.) (TOU) utility rate strategies.
Peak Override Wind-up Timer Overrides peak signal to allow charging of heating
(Optional in EXT series only.) elements during a control period. (Emergency heat
for a preset time initiated by user only.)
Power Line Carrier Provides wireless control signals for utility on-peak
and off-peak periods.
Utility Mode Timer Initiates a time-based on-peak period upon the
(Optional in EXT series only.) completion of a utility controlled charging period.
Peak Control Sequencer Monitors voltage of charging circuits to signal peak
(Optional in EXT series only.) conditions when line voltage interruption is used for peak
control.
Low Voltage Control Module Provides low voltage control of element charging
(Optional in S series only.) and fan operation.
Safety Devices: Core Charging High Limit De-energizes heating elements if maximum core
Switch(es) temperature is exceeded. (Automatically resets when core
temperature decreases.)
Discharge Fan High Limit Monitors discharge air temperature and de-energizes fan(s)
Switch(es) if maximum temperature is exceeded. (Automatically
resets when discharge air temperature decreases.)
Service Light Indicates the core charging high limit switch has
interrupted power to the heating elements.
Tip Over Switch Disables heating elements and fan(s) if unit
(Units equipped with security is not in the upright position.
base only)
D. MAINTENANCE/CLEANING
As with most heating systems, air borne particles in the room may be drawn into the heating system and oxidized.
As these air borne particles are expelled back into the room, they may accumulate on the heater or other surfaces. Over
time, these particles may appear as a black residue, commonly referred to as soot. High concentrations of air borne
particles from such things as aerosols, dust, candles, incense, pet hair, high humidity, smoke or cooking can contribute to
poor indoor air quality and accelerate this process.
To minimize the black residue build up, clean the outer surface of the heater on an annual basis or as needed. Wash
the cabinet only when cool with any liquid cleaner. Do not use scouring powders or furniture polish. Steffes ETS
recommends using "Soft Scrub with Bleach" brand cleanser or equal. Regularly vacuum around all sides of the heater.
•Service Light
A red service light located in the bottom right corner of the grill (See Figure 6) will illuminate whenever the core
charging high limit is tripped. The illumination of the light may indicate violated clearances or possibly an operational
difficulty within the heater. The unit will function with the service light illuminated; however, long-term operation may
reduce the life expectancy of internal components. If the light illuminates repeatedly, notify a service technician.