PLUS Line Instruction Manual Supplement
PLUS & 
PLUS WATER HEATERS WITH 
4 Start-up
Follow Boiler Manual procedures
1.Follow all procedures in the boiler manual to start up and verify operation of the boiler.
Set space heating operation
Verify space heating mode
1.Press the “Mode” button until the display shows “Para.” This is the parameter mode.
2.Press the “Step” button until the display first digit shows “3.”
3.The last digit must show “1.” If any other number displays, press the “+” button until “1” shows in the
Set space heating target temperature
1.Press the Ultra control panel “Step” button until the display first digit shows “4.” The right 3 digits show the outlet water temperature setting.
2.Press the “+” or
a.Outdoor sensor installed — Setting is the target temperature for outdoor temperature at or below 32 °F. At higher outside temperatures, the Ultra PhD control module calculates the target temperature. (See Ultra Control Supplement for detailed discussion of outdoor reset.)
When a summer/winter switch is used, closing the switch will disable the boiler (space heating) circulator during summer operation.
b.Outdoor sensor not installed — Setting is the target temperature at all times.
3.Press the “Store” button to save the setting.
PLUS water heater operation
1.The PLUS water heater thermostat must be connected to low voltage terminal strip terminals 3 and 4 as shown on page 10.
2.When the water heater thermostat calls for heat, the module shuts down the boiler circulator, activates the water heater circulator and immediately sets target outlet water temperature to 190°F. This provides automatic priority heat allocation to the indirect water heater for maximum response and recovery.
3.The water heater circulator continues for 30 seconds after the heating cycle to deliver the most possible heat.
Check PLUS operation setup
1.Go to step 2 if the control is in Parameter mode already. Press the “Mode” button until the display shows “Para” (parameter mode).
2.Press the “Step” button until the display first digit shows “2.”
3.The last digit must show “1.” If any other number displays, press the “+” button until “1” shows in the
4.The Ultra PhD control module turns on the PLUS circulator when the indirect water heater operating control closes. The control module shuts off the boiler circulator (stops space heating) during calls for DHW heating.
Verify operation — space heating
NOTE: “[ _ _ _ _ ]” in the following indicates the characters that should show on the Ultra display panel. “180” in the right 3 places means the display shows the measured boiler water temperature. The number shown will not necessarily be 180.
1.Turn down aquastat on PLUS tank. If necessary, turn off power and remove one of the PLUS aquastat wires to ensure boiler will not receive a DHW heat call.
2.Turn off power to boiler at service switch.
3.Wait a few seconds, then turn on power to boiler.
[A180]
[0180] (no call for heat)
4.Raise room thermostat to call for heat.
[5180] (blower/circulator on) The blower and boiler circulator energize and the control checks for air flow.
[1180] (prepurge) After a few seconds delay (control self- check), blower speed will increase to ignition speed. The blower will run in prepurge for 10 seconds.
[2180] (ignition) After prepurge, the control module opens the gas valve and starts ignition spark.
a.If burner flame proves within 4.5 seconds, burner continues to fire. Burner will fire at
— 50% of maximum input — for about 10 seconds to allow flame to stabilize.
b.If burner flame does not prove within 4.5 seconds, control module attempts ignition sequence again. Flame must prove within 5 attempts or control will lockout (display will show [E 02]).
c.Verify flame failure operation by closing boiler manual gas cock to prevent gas flow. Open manual gas valve after testing.
Part number IWHA016A/1103 | 11 |
