Form 2263-110506 MMP2 Installation and Operating Instructions ©2017 ZONEFIRST
®
Leaving Air Sensor
(Mounted in Supply Air before Zone Dampers)
Model ZPS
LAS Terminals
On Zone Panel
NOTE: If the ZPS is not used, the NO SENSOR jumper located just above
the LAT terminals must be on the pins.
After installing the ZPS, use the chart supplied with the ZPS to check the
Ohm reading for the appropriate duct temperature.
TROUBLESHOOTING
The MMP2 is a very simple control to troubleshoot, especially with the
LED indicators. The only other device needed is a simple Volt/Ohm meter.
Almost all problems can be traced to an external component or wiring to
the MMP2. While the MMP2 has been designed to operate under
extreme voltage conditions and is fuse protected, like any computer the
micro-processor can hang up and not operate properly.
Turn off the power to the panel for several seconds until the LEDs got out
and then turn the power back on to see if the panel resets. In many
instances this resolves the problem.
The first check is for 24VAC Power to the panel. When there is power the
Green Power LED will be lit. If not check the transformer and the power
supply to it.
Zone(s) Not Calling
Each zone has a Green LED next to the zone relay when it is calling. The
LED being lit shows that the call is being recognized by the MMP2. If a
zone is supposed to be calling and the Zone LED is not on, check for 24VAC
across the thermostat terminal C and the Y, if a Cool call, W if a Heat Call,
or G if a Fan call. If there is no voltage here at the panel the panel is not
getting the signal from the thermostat. The problem is mis-wiring, a
broken wire or a problem in the thermostat. To check the zone on the
panel, place jumper from R to Y to simulate a Cool call, R to W to simulate
a Heat call, or R to G to simulate a Fan call. By jumping these terminals
the zone LED will activate.
Zone(s) Will Not Shut Off
If a zone will not stop calling, the Zone LED should still be on. Depending
on the call disconnect the Y, W or G wire from the zone terminal strip on
the panel. The call from that zone will drop out when the thermostat wire
is removed. Check the thermostat wiring for a mis-wiring or short that
keeps the zone calling.
If the thermostat wire is disconnected from the proper terminal on the
zone and the zone LED remains lit, re-boot the panel to see if the call
drops. If the call still stays on, turn power off to the panel for 10 seconds
and then turn back on. Once power is restored and the thermostat is
disconnected the call should drop from the zone, if not replace the panel.
Damper Motor Checkout Procedure
In order to determine the operation of the damper motors, the panel
motor plug can be checked to determine if power is being supplied from
the panel. If there is power at the motor plug, the problem may be a
broken wire or poor connection in the cord or the motor itself.
To check the power to the motor from the damper plug on the panel,
switch your meter to DC Volts. Note the wires on the plug and check
across either Positive and Negative wires. Note that each plug has two
positive leads and two negative leads. Both positive and both negative
leads are wired together. The meter will read either Plus (+) or Minus (-)
12VDC depending if the damper is to be Open or Closed respectively.
DAMPER CLOSED
-12VDC
NOT USED
NOT USED
POSITIVE (+)
POSITIVE (+)
NEGATIVE (-)
MOTOR PLUG
VDC
-12VDC
NOT USED
NOT USED
POSITIVE (+)
POSITIVE (+)
NEGATIVE (-)
MOTOR PLUG
-12VDC
-12VDC
NOT USED
NOT USED
POSITIVE (+)
POSITIVE (+)
NEGATIVE (-)
MOTOR PLUG
VDC
DAMPER OPEN
+12VDC
NOT USED
NOT USED
POSITIVE (+)
POSITIVE (+)
NEGATIVE (-)
MOTOR PLUG
VDC
+12VDC
NOT USED
NOT USED
POSITIVE (+)
POSITIVE (+)
NEGATIVE (-)
MOTOR PLUG
+12VDC
+12VDC
NOT USED
NOT USED
POSITIVE (+)
POSITIVE (+)
NEGATIVE (-)
MOTOR PLUG
VDC
When using multiple dampers on a single zone, please note to have no
more than 10 dampers on a single zone. Adding dampers beyond the
recommended number may cause all dampers to be slow to operate and
may not fully cycle between open and closed.
