Test Modes - American Standard YSC036A Installation, Operation And Maintenance Manual

Table 10. Service test guide for
component operation
Test Step Mode Fan
Fan On
1
Minimum On
Ventilation
2 Economizer On
Test Open
3 Cool On
Stage 1
4 Cool On
(Note 3) Stage 2
5 Reheat On
(Note 3)
6 Heat On
(Note 3) Stage 1
7 Heat On
(Note 3) Stage 2
Notes:
1 - The condenser fans will operate any time a compres-
sor is "On.
providing the outdoor air temperatures are within the
operating values.
2 - The exhaust fan will turn on anytime the economizer
damper position is equal to or greater than the ex-
haust fan setpoint.
3 - Steps for optional accessories and non-applicable
modes in unit will be skipped.

Test Modes

There are three methods in which the
"Test" mode can be cycled at LTB-
Test 1 and LTB-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 start-up of the 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 start-up
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
36
Econ
(Note 2) Comp1 Comp 2
Minimum
Position Off Off
Setpoint 0%
Selectable Off Off
Open Off Off
Minimum (Note 1) Off
Position On
Minimum (Note 1) (Note 1)
Position On On
Minimum On On
Minimum Off Off
Minimum Off Off
though the resistance is left on
the test terminals.
3. Auto Test Mode - This method is
not recommended for start-up
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 unit test steps, test modes, and
step resistance values to cycle the
various components, refer to
Table 10.
Electro Mechanical Controls
Upon power initialization, the Gas
Ignition Module (IGN) 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 System
LED located on the IGN module is
turned "On" within one second of
power-up if internal operation is
okay.
Heat 1 Heat 2 Ohms
Off Off 2.2K
Off Off
Off Off 3.3K
Off Off 4.7K
Off Off 6.8K
Off Off 33K
On Off 10K
On On 15K
Electromechanical
Controls Test
Procedure
See unit schematic for correct wire
numbers.
Fan Test and Minimum
Ventilation
Connect red thermostat wire (R) to
black thermostat wire (G).
Economizer Cooling
Connect a jumper wire across OTS
on Economizer Control (ECA).
Connect red thermostat (R) wire to
yellow thermostat wire (Y1).
Cool 1
Connect red thermostat wire (R) to
yellow thermostat wire (Y1).
Cool 2
Connect red thermostat wire (R) to
yellow thermostat wire (Y2).
Heat 1
Connect red thermostat wire (R) to
brown thermostat wire (W1).
Heat 2
Connect red thermostat wire (R) to
brown thermostat wire (W2).
Pre-Start
RT-SVX21F-EN