R
2800 LAURA LANE • MIDDLETON, WI 53562 • (800) 288-9383 • FAX (608) 836-9044 • www.tcsbasys.com
10
turn on for that length of time on powerup. Setting
each unit to a different delay allows you to soft start
your system, and thus prevent this peak.
Checkout & Troubleshooting
CHECKOUT
Note:
The fan has a minimum on and off time of 30
seconds. The heating and cooling stages have a mini-
mum on and off time of 2 minutes.
You may verify the status of heating and cooling stag-
es and fan in monitoring screens 5, 6, and 7, which
are accessed by pressing the SERVICE STATUS but-
ton.
V1.0
SZ1018
TCS
MON
12:00 AM 72F
1. Verify all wiring prior to powering the thermostat.
2. Turn power on. The thermostat will display a
momentary screen with the model number , and
then the main monitoring screen with the time, day
and current temperature.
3. Press the PROGRAM SETUP button until you
reach the screen # 14 which allows you to set the
occupant setpoint adjustment limits. Change this to
+/-20 °F (11.1 °C). Press the PROGRAM SETUP
button once more to store the change. Then press
the SERVICE STATUS button once to exit the pro-
gramming.
4. Press the FAN SWITCH button to access the
fan mode and change the mode to AUTO. Press
the FAN SWITCH button once more to store the
change. Press the SYSTEM SWITCH button to
access the system mode and change the mode to
AUTO. Press the SYSTEM SWITCH button once
more to store the change.
5. Verify that the thermostat is operating in the occu-
pied mode by making sure that the top LED is lit. If
not, press the OVERRIDE button. The LED should
light up.
6. Take note of the current temperature reading.
Press the WARMER (up) button. The setpoint
adjustment screen should now be showing. Press
the WARMER button until the heating setpoint is
greater than the current temperature by at least
five degrees. The fan will come on. The heating
stage(s) will sequence on after 30 seconds.
7. Press the cooler (down) button until the heating
setpoint is one degree less than the current tem-
perature. The heating stage(s) will sequence off.
The fan will turn off 30 seconds after the last heat-
ing stage.
Use programming steps #28 through #32 to program
the operating parameters for analog output 1. Use pro-
gramming steps #33 through #38 to program the oper-
ating parameters for analog output 2.
Select whether the analog output is set for heating,
cooling or aquastat. Select direct or reverse action.
Select whether you want the analog output to modulate
from 4 to 20mA or 0 to 20mA. Select the unoccupied
action ("20mA or 0 / 4mA" will hold the analog out-
put device open or closed during unoccupied times.
"Modulating" will modulate the analog output device to
maintain the unoccupied heating or cooling setpoint.).
Enter a proportional band (throttling range) in degrees.
P+I OPTION
The SZ1018 also have a P+I option. Without enabling
this option, stages turn on and off based on tem-
perature vs. setpoint alone, as described above. By
enabling this option, you add a time factor to anticipate
heating and cooling.
DI2 AQUASTAT
DI2 may be set as an aquastat function. When DI2 is
selected to have an aquastat function, and the analog
output is selected to have an aquastat function, opera-
tion is as follows.
With DI2 "Open", the analog output operates in cool-
ing mode, and uses selected direct or reverse action.
When DI2 is "Closed", the analog output operates in
heating mode, and uses the opposite of the selected
direct or reverse action.
SMART RECOVERY
“Smart Recovery” may be enabled. It ramps the set-
point 4°F/hr. when going from the unoccupied mode to
the occupied mode. At the beginning of the occupied
mode, the occupied setpoint will be reached, many
times without the need for the second stage to come
on. This feature is automatically disabled when DI3 is
set to external time clock.
BUILT-IN DELAYS
The SZ1018 have delays built into the programming
sequences to protect equipment. The fan has a mini-
mum on and off time of 30 seconds. When the fan is
in AUTO or COOL mode, it will come on 30 seconds
before the heating or cooling stages are allowed to
sequence on, and remain on for 30 seconds after the
heating or cooling stages sequence off. Each stage
has a minimum on and off time of two minutes. There
is a minimum of two minutes between when one stage
turns on until the next stage is allowed to turn on, as
well as when one stage turns off until the next stage is
allowed to turn off.
DELAY ON POWERUP
The SZ1018 have an adjustable delay on powerup.
When several thermostats are used at one location,
and the power goes out, most thermostats turn all of
the units back on at the same time on regain of power,
creating a peak. The thermostat allows you to set a
value, in seconds, where no outputs are allowed to
