Honeywell TrolaTemp MABS EZ-2 Product Data page 10

MASTERTROL® AUTOMATIC BALANCING SYSTEM™ (MABS®) EZ ZONE (EZ-2 AND EZ-4) CONTROL PANELS
Table 5. Purge DIP switch settings.
DIP Switch No.
1 Off
1 On
2 Off
2 On
LED Indicators
The panel features several LED status indicators visible
through a window in the cover. See Table 6.
Table 6. LED Status Indicators.
LED Color Lighted
Heat Red Heat call
Cool Green Cool call
Purge Amber Purge
mode
Fan Green Fan only
call
Em Red Emergency
Heat heat switch
on or ther-
mostat in
emergency
heat
Zone Green Damper
1,2, open or
3,4 moving
Re-Booting the Microprocessor
When conditions hang up the microprocessor, press and
release the Boot button to re-boot the system and enter the
Purge mode.
69-1360–2
Setting Action
3.5 minutes
2 minutes
Panel control of
fan in Purge
HVAC control of
fan in Purge
Status
Not
Lighted Flashing
Not in heat ZMS high
call temper-
ature limit
tripped
Not in cool ZMS low
call temper-
ature limit
tripped
Not in _
Purge
mode
No fan only _
calls
Not in _
emergency
heat mode
Damper _
closed
ZoneMAX Sensor Leaving Air Temperature Sensor
The ZMS (not included) is a duct-mounted temperature probe
that monitors the supply of air temperature to control capacity
and prevent over-heating or coil icing. The sensor attaches to
the TL terminals at the upper left corner of the panel. See Fig.
9.
IMPORTANT
The ZMS wires must be at least 12 in. away from line
voltage wiring to ensure correct operation. When not
possible, shielded cable must be used.
ZoneMAX Sensor Configuration
DIP switches 2 and 3 set the ZoneMAX Sensor temperature
limit. See Table 7. The recommended setting for fossil fuel/
heat pump systems is 160°F (71°C). For heat pump systems,
the recommended setting is 120°F (49°). The cooling
temperature limit can be set to 40°F (4°C) or 48°F (9°C).
Table 7. ZoneMAX Sensor Configuration.
DIP Switch
No.
2
3
OPERATION
If the system trips due to exceeding a high or low temperature,
the heating or cooling system shuts down and the fan
continues running to dissipate the conditioned air from the
plenum. If the low limit was tripped, the cool LED flashes
continuously until it resets. If the high limit was tripped, the
Heat LED flashes continuously until it resets.
The ZoneMAX Sensor resets and allows normal system
operation when the supply air temperature rises ten degrees
in cooling mode, or falls ten degrees in heating mode. The ten
degrees provide adequate time to prevent short cycling of the
unit.
Circuit Breaker Protection
A built-in thermal circuit breaker protects the panel against
shorts in the thermostat and damper wiring and the remote
occupied/unoccupied switch. It does not protect against shorts
in the HVAC equipment wiring into the panel.
OPERATION
None of the LEDs light when the circuit breaker tripped. The
fuse is a yellow square or rectangular disk located right of the
TR1 and TR2 terminals. If it is hot to touch, remove panel
power for ten seconds to allow the circuit breaker to cool off
and reset.
10
Setting
Off (Default)
ZMS 160°F (71°C) ZMS 120°F (49°C)
heating limit heating limit
ZMS 40°F (4°C) ZMS 48°F (9°C)
cooling limit cooling limit
On