Startup
RT-SVX34F-EN
55
Starting the Unit
Before closing the main power disconnect switch, insure
that the “System” selection switch is in the “Off” position
and the “Fan” selection switch for Constant Volume or SZ
VAV units is in the “Auto” position.
Close the main power disconnect switch and the unit
mounted disconnect switch, if applicable.
HIGH VOLTAGE IS PRESENT AT TERMINAL BLOCK HTB1
OR UNIT DISCONNECT SWITCH.
Upon power initialization, the RTRM performs self-
diagnostic checks to insure that all internal controls are
functional. It also checks the configuration parameters
against the components connected to the system. The LED
located on the RTRM module is turned “On” within one
second of power-up if internal operation is okay. The
economizer dampers are driven open for 5 seconds then
fully closed (if applicable).
When an economizer is installed DO NOT ENTER the TEST
mode until all calibration startup functions have been
completed. Otherwise, the economizer actuator and
power exhaust output may not function properly during
any of the test mode steps. Allow 2 minutes after unit
power up to complete economizer calibration before
entering the test mode function.
Use the following “Test” procedure to bypass some time
delays and to start the unit at the control panel. Each step
of unit operation can be activated individually by
temporarily shorting across the “Test” terminals for two to
three seconds. The LED located on the RTRM module will
blink when the test mode has been initiated. The unit can
be left in any “Test” step for up to one hour before it will
automatically terminate, or it can be terminated by
opening the main power disconnect switch. Once the test
mode has been terminated, the LED will glow
continuously and the unit will revert to the “System”
control, i.e. zone temperature for constant volume units or
discharge air temperature for variable air volume units.
Test Modes
There are three methods in which the “Test” mode can be
cycled at LTB1-Test 1 and LTB1-Test 2.
1.
Step Test Mode - This method initiates the different
components of the unit, one at a time, by temporarily
shorting across the two test terminals for two to three
seconds.
For the initial startup of either a Constant Volume or
Variable Air Volume (Single Zone or Traditional) unit,
this method allows the technician to cycle a
component “on” and have up to one hour to complete
the check.
2. Resistance Test Mode - This method can be used for
startup providing a decade box for variable resistance
outputs is available. This method initiates the different
components of the unit, one at a time, when a specific
resistance value is placed across the two test
terminals. The unit will remain in the specific test mode
for approximately one hour even though the
resistance is left on the test terminals.
3. Auto Test Mode - This method is not recommended for
startup due to the short timing between individual
component steps. This method initiates the different
components of the unit, one at a time, when a jumper
is installed across the test terminals. The unit will start
the first test step and change to the next step every 30
seconds. At the end of the test mode, control of the unit
will automatically revert to the applied “System”
control method.
For Constant Volume or Variable Air Volume test steps, test
modes, and step resistance values to cycle the various
components, refer to
Table 31, p. 56
-
Table 36, p. 58
.
Service Test Switch Location
A toggle service switch has been offered as a standard
option to provide hassle free startup option for the service
person in the field. This toggle switch is located under the
control panel behind the front cover.
WARNING
Live Electrical Components!
During installation, testing, servicing and
troubleshooting of this product, it may be necessary to
work with live electrical components. Have a qualified
licensed electrician or other individual who has been
properly trained in handling live electrical components
perform these tasks. Failure to follow all electrical safety
precautions when exposed to live electrical
components could result in death or serious injury.
Table 30. Service test switch
