AERCO Esteem O&M Manual - Manual (Page 52)

46
Operation Verifi cation - Domestic
Hot Water
1. As outlined in the verification for space
heating, repeat STEPS 2 through 4.
2. Raise the DHW aquastat setting to initi-
ate a call for heat. As in the space heating
operation the display should show:
• [ 5140 ] This is a fan / air flow check. The
burner blower will be energized momen-
tary prior to the prepurge cycle.
• [ 1180 ] This is prepurge cycle. The burn-
er blower and DHW circulator become
energized and the 10 second prepurge
cycle begins.
• [ 2180 ] The boiler will begin the igni-
tion sequence. The same sequence of
establishing flame, trail for ignition and
attempts for ignition as described in the
space heating applies for domestic water
heater.
• [ 4180 ] This indicates normal operation
for DHW. The burner will begin modu-
lating its input to maintain the DHW set
point. The burner will not go into the low
input rate for the 1 minute flame stabili-
zation period that occurs in CH mode.
3. Lower the DHW aquastat to satisfy the
call for heat.
• [ 1180 ] The post purge cycle begins.
The control module closes the gas valve
and the blower continues for a 30 sec-
ond post purge.
• [ 8180 ] The DHW circulator will continue
for a 30 second post pump cycle. If
another DHW call for heat is initiated the
boiler ignition sequence will begin imme-
diately.
• [ 0180 ] Boiler is in standby MODE wait-
ing for a space heating or DHW call for
heat.
4. Verify the DHW operation of the boiler by
repeating the outlined operation sequence
several times.
5. Return the DHW aquastat and room ther-
mostat to the desired setting.
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