Purge Air From All System And Zone Piping - Honeywell AQ25A Series Technical Reference Booklet

c. Depending on the settings for the AUX.PUMP (line
voltage-rated dry contacts) and the AUX OUT (low
voltage-rated dry contacts), either or both of these
relays may also close.
4. Turn down the setpoint of one thermostat. The zone
valve or pump associated with that zone should turn off.
The Boiler T-T and Boiler pump relay outputs should be
de-activated.
5. Repeat steps 3 and 4 for all zones to verify each zone is
operating correctly. Thermostats may be exercised
individually or all together to accelerate the check out
process.
6. Turn up the DHW Aquastat to simulate a call for hot
water.
a. If the DHW device is a pump, the DHW relay output
energizes immediately. The Boiler pump relay
remains off.
b. If the DHW device is a valve, the Boiler pump relay
energizes after a delay to allow the zone valve to
fully open. This delay is selected from the
EQUIPMENT SETUP>DHW>DHW VLV.OP menu
option.
c. Turn up the setpoint of one of the AQ1000 zone
thermostats.
(1) If the DHW relay is configured to control a pump,
and DHW PRIOrity is selected, the Boiler and the
associated zone pump's relay remain off.
(2) If the DHW relay is configured to control a valve,
and DHW PRIOrity is selected, the Boiler pump
activates after a delay for the DHW zone valve to
open, but the associated zone relays remain off.
(3) If DHW PRIOrity is disabled, space heating zone
pumps and valves should operate during a call for
DHW.
AQ251 SERIES BOILER RESET CONTROL PANELS
7. Turn down the DHW Aquastat to end the call for hot
water. Space heating operation should continue (if DHW
priority is disabled) or resume (if DHW PRIOrity is
enabled).
6 PURGE AIR FROM ALL SYSTEM
AND ZONE PIPING
The PURGE operation on the AQ251 Control Panel allows the
installer to purge all zones (loops) sequentially, or each zone
individually, for a period of time, PURGE TIME, which selected
from the EQUIPMENT SETUP >TEST AND PURGE > PURGE
submenu. The purge time can be adjusted in increments of 1
minute, up to a maximum of 30 minutes per loop to be purged.
After you have defined which loops to purge (all loops, or an
individual loop) and for how long (using the AQ251's menus),
position the indicator arrow (←) beside the START PURGE
option and press the OK button. The START PURGE display
will change to STOP PURGE and the AQ251 display begins
counting down the time remaining for the purge cycle.
Purging All Loops
When the purge time has elapsed for the first loop, the control
proceeds to the next loop and performs the purge operation on
each loop in sequential order. After all selected loops have
been purged, the display shows PURGE COMPLETED.
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