Schwank STS-JZ Installation & Owner's Manual page 59

Options For 24V Thermostat Control:
NOTE: Fenwal DSI has an onboard relay switch to control the blower motor (120 Vac)
and allows for heater control with either 24V or 120V thermostat.
The Fenwal DSI has a post-purge feature.
A 24V Thermostat MUST be used to enable the post-purge feature.
A line voltage thermostat will disable the post-purge feature
Low Voltage Digital Thermostat
(24 Volts - °F or °C selectable)
Not for use in corrosive or wet environments
TruTemp Thermostat (24Vac - 3-Wire)
True comfort control for radiant heating
systems - senses and averages ambient and
radiant temperatures.
Occupancy sensor with auto set-back of 9°F
(5°C).
Do not use in wet or corrosive environments
Line Voltage Thermostat:
Dual Scale: °F or °C
Not for use in corrosive or wet environments
Multiple Heaters per 24V Thermostat
Relay Switch: One required for each burner
after the first burner in a zone (1st burner
connects to 24V thermostat)
Refer to wiring diagram Page 36
(field installed at or in burner)
NOTE: FENWAL DSI has built in relay for
blower operation
24 Volt Option: Control Center
Use when Multiple Tube Heaters are
controlled by a single 24V Thermostat or
TruTemp
(for field mounting)
JS-0569-WR
JM-0150-XX
JL-0772-XX
JS-0568-CC
JM-0303 –KT
59
STS-JZ-F / IQ-F I&O Manual Z83.20-2016
IM101220
RD: APR 2019
RL: 20C