Weil-McLain Ultra Electric Water Heater Configuration guide

Thismanualmustonlybeusedbyaqualifiedheatinginstaller/servicetechnician.
Readallinstructions,includingtheBoilerManualandothersupplements,before
installing.InstallPLUSorUltraPLUSindirect-firedwaterheaterasexplainedin
thePLUSLineManual.InstallUltraboilerasexplainedintheUltraBoilerManual.
Performstepsintheordergiven.Failuretocomplycouldresultinseverepersonal
injury, death or substantial property damage.
Part No.IWHA016A/1103
Gas-firedWaterBoilers
with
PLUSPLUS
PLUSPLUS
PLUS LINELINE
LINELINE
LINE
Indirect-FiredWater Heaters
PLUS & PLUS water heaters with
Instruction Manual Supplement

Part number IWHA016A/1103
2
PLUS Line Instruction Manual Supplement
PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Contents
The following defined terms are used throughout this manual to bring attention to the presence of hazards of
various risk levels or to important information concerning the life of the product.
Indicates presence of hazards that will cause severe personal injury, death or substantial property
damage.
Indicates presence of hazards that can cause severe personal injury, death or substantial property
damage.
Indicates presence of hazards that will or can cause minor personal injury or property damage.
Indicates special instructions on installation, operation or maintenance that are important but not
related to personal injury or property damage.
Hazard definitions ............................................................................... 2
Please read before proceeding........................................................... 2
1. Install system water piping ............................................................. 3
2. Install boiler-to-water heater piping................................................ 6
3.Fieldwiring ....................................................................................... 8
4.Start-up........................................................................................... 11
Hazard definitions
Please read before proceeding
Installer Read all instructions before installing.
Follow all instructions in proper order
to prevent personal injury or death.
• This document is intended only as a supplement
totheUltraBoilerManualandPLUSLinemanual.
It’s purpose is for connection of an Ultra boiler to
a PLUS Line water heater.
User
• This document is for use only by your qualified
heating installer/service technician.
• Please refer to the Ultra Boiler User’s Information
Manual for your reference.
• Keep this supplement near the boiler for use by
your installer or technician.
Follow the PLUS Line manual to install the PLUS water heater.
Ultra boilers must be installed as directed in the Ultra Boiler Manual and
supplements.
Failure to adhere to these guidelines can result in severe personal injury,
death or substantial property damage.

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PLUS Line Instruction Manual Supplement
PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
System water piping methods
Allpipingmethodsshowninthismanual
useprimary/secondaryconnectiontothe
boiler loop. These designs ensure proper
flowthroughtheUltraboiler,forthemost
efficientandreliableoperationoftheboiler
and the heating system. For other piping
methods,consultyourlocalWeil-McLain
representative or refer to separate Ultra
boilerpipingguides.
Wall-mounted boilers — Piping can exit
bottom of boiler enclosure. See separate
wall-mountinginstructionsfordetails.
Expansiontankandmake-upwater
1. Ensure expansion tank size will handle boiler and
system water volume and temperature. Allow 3
gallons for boiler and its piping.
Undersizedexpansiontankscausesystem
water to be lost from relief valve and
make-up water to be added through fill
valve. Eventual boiler failure can result
duetoexcessivemake-upwateraddition.
2. Tankmustbe located asshown inthissupplement,
or following recognized design methods. See tank
manufacturer’s instructions for details.
3. Connect the expansion tank to the air separator
only if the separator is on the suction side of the
system circulator. Always install the system fill
connectionatthesamepointastheexpansiontank
connection to the system.
4. The piping drawings in this supplement show
diaphragmexpansiontanks.SeeFigure 1forpiping
from air separator to expansion tank and make-up
water line using a closed-type expansion tank.
5. Refer to Ultra Boiler Manual for other system
piping examples.
Diaphragm (or bladder) expansion tank
1. Always install an automatic air vent on top of the
airseparatortoremoveresidualairfromthesystem.
Closed-type expansion tank
1. See Figure 1 for piping connections when using a
closed-type expansion tank.
2. Pitchanyhorizontalpipinguptowardstank1 inch
per 5 feet of piping. Connect to tank with at least
¾" piping to allow room for air to rise.
DO NOT install automatic air vents on
closed-type expansion tank systems. Air
must remain in the system and return to
the tank to provide its air cushion. An
automatic air vent would cause air to
leave system, resulting in water-logging
the expansion tank.
Install system water piping (space heating)1
Boiler circulator
Theboilercirculatorisshippedloose.Itmustbelocated
in either the return or supply piping, as shown in the
appropriate piping diagram in this supplement or the
BoilerManual.
DO NOT use the boiler circulator in any
location other than those shown. The
boiler circulator is selected to ensure
adequate flow through the Ultra boiler.
Failure to comply could result in
unreliable performance and nuisance
shutdowns from insufficient flow.
Sizing space heat system piping
1. SeeFigures 2and 3,pages 4and5,ortheUltraBoiler
Manual for recommended piping. In all diagrams,
the space heating system is isolated from the boiler
loop by the primary/secondary connection.
2. Size the piping and components in the space
heating system using recognized design methods.
Figure 1 Expansion tank piping

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PLUS Line Instruction Manual Supplement
PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Install system water piping (space heating) (continued)1
Figure 2 Zone valve zoning plus optional
water heater piping
Zoning with zone valves
1. Connect boiler to system as shown in Figure 2
when zone valve zoning. The primary/secondary
piping shown ensures the boiler loop will have
sufficientflow.Italsoavoidsapplyingthehighhead
of the boiler circulator to the zone valves.
2. Whenusingaclosed-typeexpansiontank, connect
the expansion tank and make-up water piping as
shown in Figure 1, page 3.
3. Connect water heater (domestic hot water) piping
to indirect storage water heater as shown.
The PhD ControlModuleturnsoff
spaceheatingduringwaterheaterheating.
The boiler circulator will turn off,
preventing hot water from circulating to
the system. The flow/check valve shown
on the boiler outlet piping prevents
gravity circulation in the boiler loop
during water heater heating.
4. Controlling the system circulator
a. To cycle the system circulator from the Ultra PhD
control module, add a circulator relay wired to the
boiler circulator terminals as shown on page 8.
Legend Figure 2
1 Ultra boiler
2 Indirect water heater (water heater), if used
3 Boiler relief valve (see boiler manual for piping details)
4 Reliefvalve discharge piping(see boiler manualfor details)
5 Water heater circulator (see page 7 for suggested sizing)
6 Isolation valves
7 System circulator
8 Diaphragm (or bladder) type expansion tank (see page 3
for piping of closed-type expansion tank, if used)
9 Airseparator [withautomatic air ventonly on systemsusing
diaphragm(or bladder) type expansiontank]
10 Flow/check valves (with weighted seats to prevent gravity
circulation)
11 Purge/drain valves
12 Boiler circulator
13 Zone valves, typical
20 Make-up water supply
21 Primary/secondary connection
NOTE1: To ensure adequate flow rate through the
boiler,usethefollowingpipesizeonallboiler
loop piping (connecting boiler to and from
theprimary/secondaryconnection,item21):
Ultra-80orUltra-105–1"orlarger.
Ultra-155orUltra-230–1¼"orlarger.
Ultra-310–1½"orlarger.
Useatleasttheminimumpipingsizeabove
and pipe the boiler using only primary/
secondary piping as shown. Failure to
follow these guidelines could result in
systemproblems.

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PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Install system water piping (space heating) (continued)
Figure 3 Circulator zoning plus optional
water heater piping
Zoning with circulators
1. Connect boiler to system as shown in Figure 3
when circulator zoning. The boiler circulator
cannot be used for a zone. It must supply only the
boiler loop.
2. Install a separate circulator for each zone.
3. Whenusingaclosed-typeexpansiontank, connect
the expansion tank and make-up water piping as
shown in Figure 1, page 3.
4. Connect water heater (domestic hot water) piping
to indirect storage water heater as shown.
The PhD ControlModuleturnsoff
spaceheatingduringwaterheaterheating.
The boiler circulator will turn off,
preventing hot water from circulating to
the system. The flow/check valve shown
on the boiler outlet piping prevents
gravity circulation in the boiler loop
during water heater heating.
NOTE1: To ensure adequate flow rate through the
boiler,usethefollowingpipesizeonallboiler
loop piping (connecting boiler to and from
theprimary/secondaryconnection,item21):
Ultra-80orUltra-105–1"orlarger.
Ultra-155orUltra-230–1¼"orlarger.
Ultra-310–1½"orlarger.
1
Legend Figure 3
1 Ultraboiler
2 Indirect water heater (water heater), if used
3 Boiler relief valve (see boiler manual for piping details)
4 Reliefvalve discharge piping(see boiler manualfor details)
5 Water heater circulator (see page 7 for suggested sizing)
6 Isolation valves
7 System circulator
8 Diaphragm (or bladder) type expansion tank (see page 3
for piping of closed-type expansion tank, if used)
9 Air separator [with automatic air vent only on systems
using diaphragm (or bladder) type expansion tank]
10 Flow/check valves (with weighted seats to prevent gravity
circulation)
11 Purge/drainvalves
12 Boiler circulator
14 Zone circulators, typical
20 Make-up water supply
21 Primary/secondary connection
Useatleasttheminimumpipingsizeabove
and pipe the boiler using only primary/
secondary piping as shown. Failure to
follow these guidelines could result in
systemproblems.

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PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Install boiler-to-water heater piping2
Combined space heating/water
heating applications
1. Figure 4showsrecommendedpipingbetweenUltra
Boiler and PLUS water heater. All show direct
connection of the water heater piping to the boiler
because the boiler circulator shuts down during
water heater operation.
2. Table1, page 7, uses the recommended flow rates
fortheUltraPLUSwaterheaterandminimumflow
rates for the Ultra boiler to provide recommended
water heater piping and circulator sizing. If using
another circulator, verify it is at least equal to the
Taco selection given in Table 1. For general
informationonheadlossthroughboilerandboiler-
to-water heater piping, refer to the Ultra Boiler
Manual.
3. Procedure:
Step 1:Select Ultra Boiler model and PLUS water
heater model in Table 1.
Step 2: Readrecommendedminimumflowrate,GPM,
in table.
Step 3: Read across to find recommended minimum
pipesizeforboiler-to-waterheaterpiping.
Step 4: Read across to find recommended Taco
circulatormodel.Useacirculatorwithapump
curveatleastequaltotheTacocirculatorshown.
SeeFigure 6,page 7forpumpcurvesoftypical
Tacocirculators.
Figure 4 Boiler-to-water heater piping:
Combined space heating/water
heating application
3 Boiler relief valve (see Boiler Manual for piping details)
4 Relief valve discharge piping (see Boiler Manual for details)
5 Water heater circulator — must be at least equal in capacity to
circulator recommended inTable 1, page 7
6 Isolation valves
10 Flow/check valve (with weighted seat to prevent gravity circulation)
11 Purge/drain valves
Figure 5 Boiler-to-water heater piping:
Dedicated water-heating only
application
Dedicated water-heating only
applications
1. Figure 5showsrecommendedpipingbetweenUltra
Plus Boiler and PLUS water heater for dedicated
water-heating only applications.
2. Pipesizing:
Table 2, page 7, provides the recommended
minimumpipesizeforboiler-to-waterheaterpiping.
3. Circulator:
UsethecirculatorrecommendedinTable 2,page 7.
InstallthecirculatorasshowninFigure 5.
4. Procedure:
Step 1: SelectUltraBoilermodelandPLUSwater
heatermodelinTable 1,page 7.
Step 2: Readflowrateexpectedusingthecirculator
specifiedinthelastcolumn.
Step 3: Size connecting piping as listed under
“Boilerpiping”inthetable.
3 Boiler relief valve (see Boiler Manual for piping details)
4 Relief valve discharge piping (see Boiler Manual for details)
5 Water heater circulator — (see Table 2, page 7)
8 Expansion tank (diaphragm or bladder type)
6 Isolation valves
10 Flow/check valve (with weighted seat)
11 Purge/drain valve
20 Fill line to fill valve (item 23)

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PLUS Line Instruction Manual Supplement
PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Notes Tables 1 and 2
Table 1 Combinedspaceheating/waterheating applications (seeNotes)
Install boiler-to-water heater piping(continued)2
1. First hour ratings in Tables 1 and 2 are based on:
• 115°F or 140°F domestic outlet water supply
temperature from water heater.
• 50°F domestic water inlet temperature.
• 190°F boiler water temperature leaving Ultra boiler.
• Circulator and pipe sizes as given in the Tables.
2. If the net Btu/hr rating of the boiler is close to the
space heating load (for combined systems) — or if
there is an unusually large demand for domestic
water—increasedboilercapacitymayberequired.
Table 2 Dedicatedwater-heatingonlysystems(usingcirculator supplied with boiler) (see Notes)
Figure 6 Pump curves forTaco circulators

Part number IWHA016A/1103
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PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Figure 7 Line voltage field wiring connections (service switch provided by installer)
Field wiring3
ELECTRICAL SHOCK HAZARD —
For your safety, turn off electrical power
supply at service entrance panel before
making any electrical connections to
avoid possible electric shock hazard.
Failuretodosocancauseseverepersonal
injury or death.
Wiring must be N.E.C. Class 1.
If original wiring as supplied with boiler
must be replaced, use only type 105 °C
wire or equivalent.
Boiler must be electrically grounded as
required by National Electrical Code
ANSI/NFPA 70 – latest edition.
Installation must comply with:
1. National Electrical Code and any other national,
state, provincial or local codes or regulations.
2. In Canada, CSA C22.1 Canadian Electrical Code
Part 1, and any local codes.
Line voltage connections
1. Connect 120 VAC power wiring to line voltage
terminal strip in left compartment of electrical
entrance, as shown in Figure 7, item 1.
2. Provide and install a fused disconnect or service
switch (15 amp. recommended) as required by the
code. (See Figure 7, item 2)
Wiring boiler circulator
1. The Taco 0011 circulator supplied with the boiler
is wired one of two locations, depending on
whether system is combined space heating/water
heating or dedicated water-heating only. Boiler
circulator is shipped loose. Wire Boiler circulator
to terminals (refer to Figure 7):
a. Combined system: terminals 5, 6, and 7 (installed as
Figure 7, item 3).
b. Dedicatedsystem:terminals3,4,andgroundwirenut
(installed as Figure 7, item 5).
Wiring PLUS circulator
1. For combined systems, connect water heater
circulatortolinevoltageterminal stripterminals 3,
4 and ground wire nut. See Figure 7.

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PLUS Line Instruction Manual Supplement
PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Wiring a system circulator
1. For combined systems, to activate a system
circulatorwhentheBoilercirculatoroperates, wire
as shown at bottom of Figure 7, page 8.
2. Youmustinstallarelayas shown.DONOTwirein
parallel with the Boiler circulator. See CAUTION
in Figure 7.
Routing line voltage wiring
1. Route line voltage connections to the jacket
openings shown in Figure 8.
Low voltage connections (Fig. 9)
1. Connectlowvoltagewiringtolowvoltageterminal
strip (Figure 9, item 1) as shown in Figure 9 and
the boiler wiring diagram.
2. Route all low voltage wires through grommeted
jacketopeningtorightoflowvoltageterminalstrip,
as shown in Figure 8.
Room thermostat (space heating)
1. Forcombinedspaceheating/waterheatingsystems,
connect Figure 9, item 2, room thermostat or end
switch (isolated contact only) between terminals 5
and 6.
2. Install thermostat on inside wall away from
influencesofdrafts,hotorcoldwaterpipes,lighting
fixtures, television, sunrays, or fireplaces.
3. Thermostat anticipator (if applicable):
a. If connected directly to boiler, set for 0.1 amps.
b. If connected to relays or other devices, set to match
total electrical power requirements of connected
devices. Seedevice manufacturers’specifications and
thermostat instructions for details.
Outdoor temperature sensor
1. Outdoor reset operation applies only to combined
space heating/water heating systems.
2. Connect outdoor temperature sensor (Figure 9,
item 6) between terminals 1 and 2 to enable
outdoorresetoperationof theUltra boiler.If fixed-
temperature operation is required, do not install
outdoor sensor.
3. Mountsensoronexteriorwall,shieldedfromdirect
sunlight or flow of heat or cooling from other
sources.
4. Install a summer/winter switch (Figure 9, item 7)
acrossterminals1and2toforcefixed-temperature
operation during summer months. (When the
switch is closed, boiler will attempt to maintain
constanttemperature.)
5. Route sensor wires through the grommeted hole
at right of the electrical entrance (see Figure 8).
PLUS water heater thermostat
1. ConnectPLUSwaterheater aquastatterminals“C”
and “1” to Ultra Boiler low voltage terminal strip
between terminals 3 and 4 (Figure 9, item 3).
Additional limits
1. Connect additional limit controls and interlocks
between the terminals shown in Figure 9.
2. Controlsconnected betweenterminals6and7(see
Figure 9, item 4) will cause a soft lockout
(automatic reset). When limit(s) closes, boiler will
resume normal operation.
3. Controlsconnected betweenterminals6and8(see
Figure 9,item 5.)willcauseahardlockout(manual
reset). The boiler will only restart after the Ultra
display panel RESET switch is pressed.
Field wiring(continued)3
Figure 8 Routing field wiring

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PLUS & PLUS WATER HEATERS WITH GAS-FIRED WATER BOILERS
Field wiring(continued)3
Figure 9 Low voltage field wiring connections
Summer/winter switch (item 7) — Install a summer/winter switch, if desired, to disable the boiler
(space heating) circulator during non-heating months. Connect switch across the outdoor sensor
terminals.Whenswitchcloses,theboilercirculatorisdisabledandtheboileroperatesonlyoncallfor
DHWheating.

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Start-up4
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
theright-handdigit.Pressthe“Store”buttontosave
this setting.
Set space heating target temperature
1. PresstheUltracontrolpanel“Step”buttonuntilthe
displayfirst digitshows“4.”The right 3 digitsshow
the outlet water temperature setting.
2. Press the“+”or“-”button to change the setting to
the desired outlet water temperature. (The factory
default setting is 190 °F.)
a. Outdoor sensor installed — Setting is the target
temperature for outdoor temperature at or below
32 °F. At higher outside temperatures, the Ultra PhD
controlmodulecalculatesthetargettemperature.(See
Ultra Control Supplement for detailed discussion of
outdoorreset.)
Whenasummer/winterswitchisused,closingtheswitch
willdisabletheboiler(spaceheating)circulatorduring
summeroperation.
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
connectedto lowvoltageterminalstripterminals 3
and 4 as shown on page 10.
2. Whenthewaterheaterthermostatcallsforheat,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
theright-handdigit.Pressthe“Store”buttontosave
this setting.
4. The Ultra PhD control module turns on the PLUS
circulatorwhentheindirectwaterheateroperating
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
charactersthatshouldshowontheUltradisplaypanel.
“180”intheright 3 places meansthedisplayshows the
measuredboilerwatertemperature.Thenumbershown
will not necessarily be 180.
1. TurndownaquastatonPLUStank.Ifnecessary,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](self-check onpower-up,for afewseconds)
[0180] (no call for heat)
4. Raise room thermostat to call for heat.
[5180] (blower/circulator on) The blower and boiler
circulatorenergizeandthecontrolchecksforairflow.
[1180](prepurge)Afterafewsecondsdelay(controlself-
check), blower speed will increase to ignition speed.
Theblower willrun inprepurgefor 10seconds.
[2180] (ignition) After prepurge, the control module
opens the gas valve and starts ignition spark.
a. Ifburnerflameproveswithin4.5seconds,burner
continues to fire. Burner will fire at start-up rate
— 50% of maximum input — for about 10
seconds to allow flame to stabilize.
b. Ifburnerflamedoesnotprovewithin4.5seconds,
controlmoduleattemptsignitionsequenceagain.
Flame must prove within 5 attempts or control
will lockout (display will show [E 02]).
c. Verify flame failure operation by closing boiler
manualgascocktopreventgasflow.Openmanual
gas valve after testing.

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4
[3180] (burner on, space heating) Once flame is proven
and stable, the burner turns down to low fire for
approximately 2 minutes.
• After this low fire period, the burner is allowed to
modulate. Firing rate depends on actual outlet water
temperature versus target temperature.
5. Allow boiler to bring water temperature to target
temperature.
[6180] (target temperature reached) The burner will shut
down. The blower will run in postpurge (see below),
thenturnoff.Theboilercirculatorcontinuestorunas
long as there is a call for heat.
6. Lower room thermostat to stop call for heat.
[1180](postpurge)Whentheroomthermostatissatisfied
(callforheatended),theburnerturnsoff.Theblower
willcontinuefora15-secondpostpurge,thenturnoff.
(If another call for heat occurs, the boiler will remain
offforoneminutebeforestartingagain,andthedisplay
will show [6180].)
[0180] (no call for heat) Boiler is now in standby mode
(waiting for heat call).
7. Repeat above steps several times to verify
operation.
8. Return the room thermostat to normal setting.
Verify operation — PLUS water
heater
1. Reconnect PLUS aquastat wiring to boiler if
necessary.
2. Turn off power to boiler at service switch.
3. Wait a few seconds, then turn on power to boiler.
[A180](self-checkon power-up,fora fewseconds)
[0180] (no call for heat)
4. RaisePLUSaquastatabovetanktemperature,tocall
for heat.
[5180] (blower/circulator on) The blower and PLUS
circulatorenergizeandthecontrolchecks forair flow.
[1180] (prepurge) Blower speed will increase to ignition
speed.Theblowerwillruninprepurgefor10seconds.
[2180] (ignition) After prepurge, the control module
opens the gas valve and starts ignition spark.
a. Ifburnerflameproveswithin4.5seconds,burner
continues to fire. Burner will fire at start-up rate
— 50% of maximum input — for about 10
seconds to allow flame to stabilize.
b. Ifburnerflamedoesnotprovewithin4.5seconds,
controlmoduleattemptsignitionsequenceagain.
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 valve to prevent gas flow. Open gas
cock after testing.
[4180](burneron,PLUS)Onceflameisprovenandstable,
theburner isallowedtomodulate.Firingratedepends
on actual outlet water temperature versus target
temperature.
5. Allow boiler to bring water temperature to target
temperature.
[6180] (target temperature reached) The burner will shut
down. The blower will run in postpurge (see below),
thenturnoff.ThePLUScirculatorcontinuestorunas
long as there is a call for PLUS heating.
6. Lower PLUS aquastat to stop call for heat.
[1180](postpurge)Whentheroomthermostatissatisfied
(callforheatended),theburnerturnsoff.Theblower
willcontinuefora15-secondpostpurge,thenturnoff.
(If another PLUS call for heat occurs, the boiler will
begin the heating cycle immediately.)
[8180] (PLUS circulator run-on) The PLUS circulator
continuestorunfor30 seconds.
[0180] (no call for heat) Boiler is now in standby mode
(waiting for heat call).
7. Repeat above steps several times to verify
operation.
8. Return the PLUS aquastat to normal setting.
Operating information
1. To check operating conditions (actual and target
temperatures, for example), see page 40 in Ultra
Boiler Manual for an explanation of the Ultra
control module Information mode.
2. During normal operation (no shutdown or
lockout),theright3displaydigitsshowactualboiler
outlet water temperature.
Replace boiler jacket front door
Replace boiler jacket front door after
installation or servicing. The boiler front
door must be securely fastened to the
boiler to prevent boiler from drawing air
from inside the boiler room. This is
particularly important if the boiler is
located in the same room as other
appliances. Failure to keep the door
securely fastened could result in severe
personal injury or death.
Start-up(continued)