Ambient EB-16 Service manual

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Electric Installation, Operating & Service Manual
Installation, Operating and Service Instructions
9700609
Electric Hot Water Boiler
Manual Contents Page
1. Read Before Proceeding.................2
2. Introduction ...........................4
3. Specifications .........................5
4. Locating Boiler ........................6
5. Hydronic Piping........................7
6. Water Quality .........................10
7. Electrical Connections/Wiring ........... 11
8. Sequence of Operation.................16
9. Control Operation .....................17
10. Start-up .............................20
11. General Maintenance ..................21
12. Troubleshooting ......................22
13. Service Parts ........................25
Warranty ................................30
REVISIONS
REV EN DATE DESCRIPTION DWN CHK APVD
TITLE:
FIRST USE:
ITEM NUMBER:
MATERIAL:
---
---
---
---
---
---
DES: ---
CHK: ---
APVD: ---
SCALE: 1:2
SIZE: C
SHEET: 1 OF 1
DATE: REVISION:
DRAWING NUMBER:
---
Boiler Assembly
UNLESS OTHERWISE NOTED:
ALL DIMENSIONS IN INCHES.
TOLERANCES:
X.X ±.1 X.XXX ±.005
X.XX ±.03 ANGLE ±1°
PROPERTY OF
U.S. Boiler Company, LLC
LANCASTER, PA
THIS DOCUMENT CONTAINS CONFIDENTIAL INFORMATION
AND ITS CONTENTS ARE THE SOLE PROPERTY OF U.S. BOILER
COMPANY, LLC. ANY REPRODUCTION IN PART OR AS A
WHOLE WITHOUT THE WRITTEN PERMISSION OF U.S. BOILER
COMPANY, LLC IS STRICTLY PROHIBITED.
THIRD ANGLE
PROJECTION
A A
B B
C C
D D
4
4
3
3
2
2
1
1
TO THE INSTALLER:
Affix these instructions adjacent to boiler.
Provide model number and serial number when
seeking information and support.
TO THE CONSUMER:
Retain these instructions for future reference.
Contact heating installer or technician for all issues
and support.
Models:
• EB-16
• EB-20
• EB-24

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Electric Installation, Operating & Service Manual
DANGER
Explosion Hazard. DO NOT store or use gasoline or other flammable vapors or liquids in the vicinity of
this or any other appliance.
• If you smell gas, DO NOT try to operate any appliance - DO NOT touch any electrical switch or use any
phone in the building. Immediately, call the gas supplier from a remotely located phone.
1Read Before Proceeding
The following terms are used throughout this manual to bring attention to the presence of hazards of various
risk levels, or to important information concerning product life.
NOTICE: Indicates a hazardous situation that,
if not avoided, could result in minor or moderate
injury.
DANGER
Indicates a hazardous situation that, if not
avoided, will result in death or serious injury.
CAUTION
Indicates a hazardous situation that, if not
avoided, could result in minor or moderate
injury.
WARNING
Indicates a hazardous situation that, if not
avoided, could result in death or serious injury.
WARNING
This boiler must only be serviced and repaired by qualified installer, service agency, gas supplier, or
electrician.
• Replace controls with manufacturer-suggested replacements.
• Read, understand and follow all instructions and warnings in this manual’s sections.
• If any electrical wires are disconnected during service, clearly label wires, and assure wires are correctly
connected.
• Never jump out or bypass any safety or operating control or component.
• Assure all safety and operating controls are working correctly before placing boiler back in service.
• Annually inspect boiler.
! !
!
!
!
NOTICE: Keep these instructions near boiler for future reference.
Read and understand this document before proceeding with installation or maintenance.
Boiler is listed with Massachusetts Board of Plumbers and Gas Fitters. See Massachusetts Boards of Plumbers and
Gas Fitters website for the latest Approval Code (https://licensing.reg.state.ma.us/pubLic/pl_products/pb_pre_form.
asp). Commonwealth of Massachusetts requires this product to be installed by a licensed Plumber or Gas Fitter.

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WARNING
Burn and Electrical Shock Hazard.
!
1. Carefully read all instructions in literature packet
and labels posted on boiler before attempting
installation, startup, or service of this boiler.
Perform steps in order given. Failure to follow all
instructions in proper order could result in severe
personal injury, death or substantial property
damage.
2. Use proper personal protective equipment when
installing, servicing, or working near this boiler.
Materials of construction contain heavy metals
and/or other toxic or harmful substances that
can be hazardous to health and life and that are
known to the State of California to cause cancer,
birth defects, and other reproductive harm.
3. Do not disconnect pipe fittings on boiler or in
heating system without first verifying system is
cool and free of pressure and that your clothing
will protect you from a release of hot water or
steam. Do not rely solely on boiler temperature
and pressure gauge when making this judgement.
• Disconnect electrical supply before
installing or performing maintenance.
• Install all guards, cover plates, and
enclosures before leaving boiler in
operation.
NOTICE: Size boiler properly relative to design
heat load or, if using DHW priority, the peak
hot water load, whichever is larger. A grossly
oversized boiler will cycle excessively leading to
premature failure of boiler and its components.
Warranty does not cover damage from excessive
cycling.
4. For heating system employing convection
radiation (baseboard or radiators), use an
industry accepted sizing method such as
the I=B=R Guide RHH published by the Air
Conditioning, Heating and Refrigeration Institute
(AHRI).
5. For new radiant heating systems, refer to radiant
tubing manufacturer’s boiler size guidelines.
6. For system including indirect water heater, ensure
boiler has output called for per indirect water
heater manufacturer’s instructions.
7. A hot boiler installed above radiation level or
as required by the authority having jurisdiction
must be provided with a low water cutoff (LWCO)
device. A UL353 listed flow switch is provided
with this boiler.
8. Inspect shipment carefully for signs of damage.
Any claim for damage for shortage in shipment
must be filed immediately against carrier by
consignee. No claims for variances or shortages
will be allowed by boiler manufacturer, unless
presented within 60 days.
User/Homeowner Read Before Proceeding
WARNING
Burn and Electrical Shock Hazard.
1. A skilled and experienced service technician
should annually inspect boiler and replace any
component exhibiting damage or deterioration.
CAUTION
Burn and Electrical Shock Hazard.
Keep children and pets away from hot surfaces
of the boiler including boiler piping, vent piping,
and vent terminal.
NOTICE: Boiler may leak water at the end of its
useful life. Be sure to protect walls, carpets, and
valuables from water that could leak from boiler.
Protect your home in freezing weather. Do not
leave heating system unattended during cold
weather unless alarms or other safeguards are in
place to prevent such property damage.
1Read Before Proceeding (continued)
Installer or Qualified Service Agency Read
Before Proceeding
!
!

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Electric Installation, Operating & Service Manual
2Introduction
Introduction
• Size boiler based on total heat load of the
building.
• Calculate maximum hourly heat loss for each
heated space following procedures described in
The Hydronic Institute Manual H-22 (Heat Loss
Calculation Guide) or a method suitable for local
conditions.
• Do not oversize the boiler—correct boiler sizing is
critical for in-floor radiant heating applications.
Unpacking
• Remove packing and inspect unit for damage or
missing parts.
• Check packing list and verify all shipped loose
items are received.
• Report any concealed damage or claims to
carrier immediately.
Control Standard Features
• Three-character LED display
• Three button User Interface
• Error code display
• Element Staging and Element Start Rotation
• Dual set points for space heating and domestic
hot water
• Setting for Fahrenheit or Centigrade temperature
scales
• Water temperature heating range 90°-180°F (32°-
82°C)
• Dry fire protection
• Connections for provided flow switch
• Low water cutoff connections
• Load management control connection with
auxiliary heat source connection
• Freeze protection
• Circulator pump terminals
• 40VA transformer
• Three-wire thermostat connection
• Audible alarm
• Pump exercising
• Relay contact monitoring
• Non-Volatile memory
Product Description
Electric Boiler is a heating device that converts
electrical energy to hot water.
Kilowatts of Electricity Used per Hour x 3412 = British
Thermal Units (BTUH) Available Per Hour for Heating.
• Follow information in Table 3-1.
• Electric Boiler is constructed to conform to
American Society of Mechanical Engineers
(ASME) Boiler & Pressure Vessel Code, Section IV.
• Maximum Allowable Working Pressure Water
(MAWP) 30 PSI.
• Construction conforms to Canadian Standards
Association (CSA) Standards Electric Boilers,
C22.2.
• Important product information on boiler:
 Model number
 Manufacturer’s serial number
 BTU rating
 Heating element ratings
 Water pressure & temperature limits
 CSA listing
 ASME stamp
 Total Amps
 Clearances
• Boiler is operated by control board maintaining
water temperature. Control cycles heating
elements based on heating demand and preset
boiler outlet water temperature.
• Control also operates 120 VAC circulator pump
rating up to 5A. When thermostat calls for heat,
control will operate boiler to regulate water
temperature at pre-established set point. System
pump is on whenever thermostat calls for heat.

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Table 3-2: Dimensions and Connections
Table 3-1: Electrical Specifications, 4 Element Boiler Operating at 240 VAC
Model
Number
Boiler
Size
(kW)
Voltage
(AC)
Output
Power
(Watts)
Output
Power
BTU/
hr.
Amps
Element
Size
(Watts)
Pump
Load
(A)
Total
Amps MCA MOP
*Recommended
Copper Wire
140F
(60C)
AWG
167F
(75C)
AWG
194F
(90C)
AWG
EB-16 16 240 16,000 54,600 66.7 4,000 5 72.7 90.8 100 2 3 4
EB-20 20 240 20,000 68,200 83.3 5,000 5 89.3 111.7 125 1/0 2 2
EB-24 24 240 24,000 82,000 100.0 6,000 5 106.0 132.5 150 2/0 1/0 1
Model
Number
Height
(in.)
Width
(in.)
Depth
(in.)
Water
Inlet
(in.)
Water
Outlet
(in.)
Water
Volume
(gal.)
Approx.
Shipping
Weight (lb.)
Ship Loose Items
Flow
Switch
Tee
(NPT)
Air
Vent
(in.)
Relief
Valve
(in.)
Temp./
Pres.
Gauge
(in.)
EB-16 24 19 10 3/4 3/4 2.20 54 3/4 3/4 3/4 1/4
EB-20 24 19 10 3/4 3/4 2.20 54 3/4 3/4 3/4 1/4
EB-24 24 19 10 3/4 3/4 2.20 54 3/4 3/4 3/4 1/4
All dimensions are approximate. Manufacturer reserves the right to change dimensions and/or specifications without
notice.
*Recommended Field Wire Size per National Electric Code (NEC). Check with latest version of NEC and local codes.
No more than three (3) current-carrying conductors in raceway.
Based on ambient temperature of 86ºF (30ºC). Other ambient temperatures see NEC or CEC for correction factors.
UL-834, Section 14.2.
WARNING
Follow NEC and local building code when selecting wires and insulation.
!
What is MCA?
Minimum Circuit Ampacity (MCA) is a calculated value that specifies the minimum primary power wire size to
determine the minimum wire size required for a field wired product. The specification is necessary to guarantee the
wire will not overheat under expected operating conditions. The wire size takes into account the normal current draw,
aging of components and anticipated faults. When operating correctly, the MCA is the highest steady-state electrical
current the unit should see.
What is MOP?
Maximum Over-Current Protection (MOP) is a calculated value that determines the maximum size of the over-current
protection device (fuse or beaker). Depending on your application, there are different MOP equations, to determine
maximum breaker size required to adequately protect equipment under anticipated fault conditions. In addition, the
MOP takes into account the startup surges and components.
Supply wiring must be rated to carry the amps shown as MCA. By comparison, the over-current protection (a breaker
or fuse) must be sized to prevent the unit from drawing more current than the MOP.
3Specifications

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Electric Installation, Operating & Service Manual
4Locating Boiler
10. Minimum clearances to combustible surfaces:
TOP...................................... 9 in.
FRONT................................. 2 in.
LEFT SIDE........................... 12 in.
RIGHT SIDE........................ 12 in.
REAR.................................. 0 in.
BOTTOM............................ 10 in.
11. Minimum service clearance:
TOP.................................... 19 in.
FRONT............................... 12 in.
LEFT SIDE......................... 18 in.
RIGHT SIDE...................... 18 in.
REAR................................. 0 in.
BOTTOM........................... 15 in.
1. Boiler is intended for indoor installation only and
should not be subject to water spray or leakage.
2. Boiler is intended to be wall mounted and is
provided with mounting brackets. Use lag screws
or anchor bolts through holes provided or on 3/4
in. plywood panel.
3. Boiler must be installed with heat exchanger
vertical.
4. On uneven walls, suggest mounting surface be
provided such as two 2 x 4's.
5. Mount boiler no closer than 12 inches to wall
surface on left and 12 inches to wall surface on
right or more, depending on plumbing.
6. Maintain 19 inches top clearance for element
removal and 15 inches bottom clearance for drain
connections.
7. Allow sufficient room from front of unit to door or
wall to remove cover - at least 12 inches.
WARNING
Failure to provide minimum clearance between
boiler and combustible material may result in
fire.
8. When installed in utility room, door should be wide
enough to allow largest boiler part to enter or to
permit replacement of another appliance such as
water heater.
9. Boiler room should be vented to maintain an
operating temperature between 45-80°F (7-27°C).
WARNING
Electrical Shock Hazard.
Do not install boiler underneath a water source.
Failure to do so could result in severe personal
injury and death.
!
!

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Circulating System
1. Size circulator(s) based on total hydronic system
pressure drop and designed flow rate.
2. To prevent rapid cycling on the high limit,
adequate flow is required.
3. Maintain 15-25 PSI system pressure.
4. These water trim components are shipped loose
with each boiler:
• Water flow switch
• Pressure relief valve (30 PSIG)
• Air vent
• Temperature/pressure gauge
• Pipe nipples
5. Provided flow switch opens at approximately
3.0 GPM. Flow switch is intended for “No Flow”
situations.
6. Install flow switch vertically in horizontal pipe with
at least five straight pipe diameters on either side.
See Figure 5-1.
7. Low water cut-off device may be required
to satisfy additional local and national code
requirements.
Boiler Model @ 3.0 GPM
EB-16 37
EB-20 45
EB-24 55
Connecting Supply and Return Piping
8. When boiler is connected to heating system
utilizing multiple zone circulator, each circulator
must be supplied with a flow control valve to
prevent gravity circulation.
9. Reduce pressure back flow preventer must
be present under provisions required by
Environmental Protection Agency (EPA).
10. A pressure relief valve is supplied with each boiler
and must be installed vertically. Install at location
and discharge direction shown using pipe nipple
and elbow supplied. See Figure 5-1. Add piping
so any water discharge will not damage boiler or
other system components.
11. Install gate valves at locations in Figures 5-1
and Table 5-2, so any boiler servicing requiring
removal of water can be done quickly and easily.
Not illustrated but recommended is installation
of air vents at high points of hydronic system to
reduce initial startup time and help avoid element
burnout during entire life of heating system.
12. Follow piping arrangement as illustrated in Figure
5-1 and Table 5-2. Inlet or return pipe is located
at bottom of unit. Reverse flow will cause noisy
operation and cause very early element failure.
Drain cock is to be located at the lowest point of
piping.
13. Pipe discharge outlet of pressure relief valve
within 6 in. of the floor or drain. No threads should
be present on discharge pipe end.
14. Outlet or supply pipe line to radiation is located at
top of unit. A combination temperature/pressure
gauge is provided and should be installed close
to boiler outlet.
15. For further piping information, refer to an industry
accepted sizing method such as the I=B=R Guide
RHH published by the Air Conditioning, Heating
and Refrigeration Institute (AHRI).
5Hydronic Piping
Table 5-2: Maximum Temperature Rise °F
Boiler Model GPM
EB-16 5.5
EB-20 6.8
EB-24 8.3
Table 5-3: Flow Rate to Achieve 20°F
Figure 5-1: Flow Switch Direction

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5Hydronic Piping (continued)
Figure 5-4: Typical Water Piping
Indirect Water Heater
(IWH)
Expansion Tank
Fill Valve
Backflow Preventer
Cold Water Return
Air Separator
& Air Vent
Full Port
Isolation
Valve
Flow Check
IWH Circulator
Full Port Isolation Valve
Full Port
Isolation
Valves
Full Port Isolation Valves
Drain Valve
Full Port
Isolation
Valves
Drain Valve
Pressure Relief Valve
Full Port Isolation Valves
Provided
Flow Switch
Union
Zone Circulators
System
Circulator
System
Zone
Valves
To System
Full Port
Isolation
Valves
To System Zone Circulators
Full Port Isolation Valves
Full Port Isolation Valves
System Zone Valves
System Return
Wye
Notes: 1. Unions and full port service isolation valves vary with each installation. 2. Refer to wiring diagram 7.2 and 7.3.
Pipe within 6" of floor or Drain No Threads on Drain End

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5Hydronic Piping (continued)
Figure 5-5: Primary/Secondary Piping with Zone Pumps
12"
max
Optional Full Port
Isolation Valves
Optional Full Port
Isolation Valves
Flow Check Valves
Heating
Circulators
Fill Valve
Backflow
Preventer
Expansion Tank
Air Separator
Dirt & Magnetic Filter
(High Recommended)
Optional Full Port
Isolation Valves
Heating
Circulators
Optional Full Port
Isolation Valves
Flow Check Valves
Drain Valve
Pipe within 6"
of floor or Drain
No Threads on
Drain End
Pressure
Relief
Valve
Union
Union
Provided
Flow Switch
Full Port
Isolation
Valves
Full Port
Isolation
Valves
To System
From System
Notes:
1. Unions and full port service isolation valves vary with each installation.
2. Refer to wiring diagram 7.2 and 7.3.
Pump

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6Water Quality
1. Poor water quality causes oxidation, scaling,
corrosion, and fouling, which can severely
damage the heating element and pressure vessel.
NOTICE: Warranty does not cover component
failure caused by scale build-up or poor water
conditions.
2. Since water quality varies by location, the installer
should consult a qualified water treatment expert
about developing a water treatment plan.
3. A proper water treatment plan and regular boiler
maintenance extend the boiler’s working life.
Refer to Table 6-1 for water quality requirements.
Oxygen Less than 250 ppb
pH 8.0-10.5
Chlorides Less than 250 ppm
Total Water Hardness Less than 150 ppm
Table 6-1: Water Quality
4. Adhere to the following installation
recommendations to prevent excess dissolved
gas and minerals from entering the heating loop.
5. Adhere to the following installation
recommendations to prevent excess dissolved
gases and minerals from entering the heating
loop.
• Install system makeup water valve with
backflow preventer.
• Install air-vent provided with this unit at
highest point on near boiler piping.
• Install an expansion tank designed for system
total water volume.
• Makeup water should be added at the boiler
outlet and not fed directly to the boiler.
• Keep makeup water at a minimum to prevent
scale build-up.
• Immediately repair leaks and maintain 14-25
psi system pressure.