4
DHW HEATING:
•
Target temperature is determined by
adding Parameter 1 to Parameter 33 (default 150°F and
30°F). Do not change Parameter 1 from the factory de
-
fault setting of 150°F unless the application is specially
engineered for other temperature. DHW heating default
setting is 180°F.
High limit operation: If outlet water temperature exceeds tar
-
get temperature (or 180°F, whichever is lower), high limit ac
-
tion occurs. The control module shuts the burner off showing
“b 9” followed by “26” on the display.
DHW operation (if used): The boiler is factory set to immedi
-
ately change target outlet water temperature to 180°F on a
call for heat from the DHW aquastat.
Additional Thermal Overrun Protection: High limit operation
shuts down the burner when the outlet water temperature ex
-
ceeds the target temperature. However, adverse conditions
could cause the water temperature to rise too quickly and
overshoot this temperature. The boiler control’s advanced
technology provides protection in the event of thermal over
-
run. using its electronics, the control provides two additional
levels of overrun protection:
LEVEL 1:
•
Indication would occur if supply water tem
-
perature reached 183°F. The control would display a
soft lockout code (“b 9” followed by “18” if on the supply
or “19” if on the return). The control would not operate
the burner again until the water temperature dropped
9°F below target temperature.
LEVEL 2:
•
Lockout would occur if supply water tempera
-
ture reached 200°F or if the return water reached 193°F.
the control would enter hard lockout and display an error
code (“E” followed by “18” if on the supply or “19” if on
the return).
NOTE: Hard lockout requires manually pressing the display
panel reset button to restart operation. Service technician must
troubleshoot the cause of the problem and correct it before placing
the boiler back in operation.
LOW WATER PROTECTION
This boiler comes factory equipped with a manual reset
1.
low water cutoff. In addition, the boiler control uses tem
-
peratures sensed at both supply and return areas of the
heat exchanger. If the flow rate is too low (temperature
difference too high) or either temperature is too high, the
control shuts the boiler down. This ensures boiler shut
-
down in the event of low water or low flow conditions.
Some codes and jurisdictions may accept these integral
2.
features of the control in lieu of requiring an additional limit
control or low water cutoff. Consult your local jurisdiction
for more information on low water cutoff requirements.
This boiler is controlled by a microprocessor electronic con
-
trol that senses outlet water temperature, return water tem
-
perature, and outdoor temperature (when a factory supplied,
field installed outdoor sensor is installed). This information
(plus input from external limit and operating controls) is used
to regulate boiler on/off operation and will modulate boiler fir
-
ing rate to more closely match output to demand.
ELECTRICAL SPECIFICATIONS
Boilers require 120 vac/60 HZ power supply and are not po
-
larity sensitive.
CONTROL SPECIFICATIONS
supply voltage
120 vac/60 hz
Electrical demand
10 va
Prepurge timing
10 seconds
Postpurge timing
15 seconds
Min. off time, space heating
10.2 seconds
Pump on after space htg.
0 minutes
Min. off time, DHW
10.2 seconds
Pump on after DHW
30.6 seconds
line voltage fuse, F1
5 amp fast-blow
low voltage fuse, F3
4 amp slow-blow
BOILER CIRCULATOR
The circulator has sufficient head to handle the boiler pressure
drop plus reasonable pressure drop in the connecting piping.
See the separate Installation Manual (P/N# 240006103) for
piping and flow rate information.
The boiler control’s internal relay contact is suitable for han
-
dling only the boiler circulator provided. Do not wire addi
-
tional pumps in parallel with the boiler circulator. To operate
a system circulator when the boiler circulator is running, see
the section on “Electrical Wiring” in the Installation Manual for
wiring required.
BOILER TEMPERATURE REGULATION
OPERATING TEMPERATURE (TARGET):
The boiler con
-
trol senses outlet water temperature and regulates the boiler
firing rate to achieve a target temperature, set by installer
with Parameter 4. Temperature can be set between 120°F
and 194°F.
SPACE HEATING:
•
Target temperature is fixed (equal to
Parameter 4) when outdoor reset is not installed or cal
-
culated as described under
“Outdoor Reset Operation”
when outdoor sensor is connected.
ExCEPTION:
•
See explanation of
“Supply Temperature
Boost.”
II - OPERATING INFORMATION
