Bradford White Everhot IGI-180R10 User manual

1
SERVICE
MANUAL
Tankless Gas Water Heater
Troubleshooting Guide
and Instruction for Service
(To be performed ONLY by qualified service providers)
For the Bradford White EverHot®
Interior Tankless
Gas Water Heater Models:
IGI-180 -10(N,X) IGI-180C-5(N,X)
Manual 45095A Save this manual for future reference

ey to Warning Symbols
Failure to comply with the following instructions may results in serious personal injury or
damage to the appliance.
Be careful of possible electric shock. Wiring inside this appliance may potentially be at
120 volts.
isconnect power supply to unit when carrying out the following service repairs.
Read Fault iagnosis and Wiring iagram carefully to avoid incorrect wiring.
o not disassemble. Parts within can not be exchanged or diagnosed faulty.
Please follow the instructions in the following chapters
to ensure safe and appropriate service.
After completing the service and confirming that there are no water or
gas leaks or incorrect wiring, test operation of the appliance.
2

TABLE OF CONTENTS
Section Description Page
- - - Glossary of Terms and Symbols. . . . . . . . . . . . . . . . . . . . . . . . . . . .4
I. . . . . . . . . . . .General Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
a. How to Use This Manual. . . . . . . . . . . . . . . . . . . . . . . . . .6
b. Cut way illustration. . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
c. Schematic illustration. . . . . . . . . . . . . . . . . . . . . . . . . . . .8
II. . . . . . . . . . . Specifications (General). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
a. Combustion Specifications. . . . . . . . . . . . . . . . . . . . . . . .11
b. Default Dip Switch Settings. . . . . . . . . . . . . . . . . . . . . . .12
c. Venting Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
III. . . . . . . . . . .Main Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
IV. . . . . . . . . . .Safety Device Function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
V. . . . . . . . . . . Sequence of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
a. Operation Sequence Flow Chart. . . . . . . . . . . . . . . . . . . .21
b. Sequence Timing Chart. . . . . . . . . . . . . . . . . . . . . . . . . .23
VI. . . . . . . . . . .Troubleshooting (error messages). . . . . . . . . . . . . . . . . . . . . . . . . .25
a. Quick Reference Diagnostic Points. . . . . . . . . . . . . . . . . .27
b. Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
c. Troubleshooting Flow Chart. . . . . . . . . . . . . . . . . . . . . . .31
d. Trouble Shooting Procedure. . . . . . . . . . . . . . . . . . . . . . .36
VII. . . . . . . . . . Gas Pressure Setting Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . .46
VIII. . . . . . . . . .Service Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
IX. . . . . . . . . . .Flushing Procedure for Lime Scale Removal . . . . . . . . . . . . . . . . . .54
X. . . . . . . . . . . Parts Breakdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
efer to installation and operation manual for the following reference information:
• General Dimensions
• Piping Recommendations
• Remote Control Features
• Water Flow Rates vs Temperature
3

GLOSSARY OF TERMS AND SYMBOLS
This glossary of terms and symbols is provided to assist you in understanding some of the
language used throughout this manual.
dB(A) - sound pressure level in decibels, “ ” range
DC - direct current
AC - alternating current
WFCD - water flow control device
FB - feedback information
Hz - hertz
IC - integrated circuit
BTU/H - British thermal units per hour
PSI - Pounds per square inch
LED - light emitting diode
GPM - gallons per minute
mA - milliamps
W.C. - inches of water column
mm - millimeters
NOx - oxides of nitrogen NO & NO2
OHS - overheat switch
PCB - printed circuit board
CPU - central processing unit
POT - potentiometer
rpm - revolutions per minute
SV - solenoid valve
Ø- diameter
∆°F - delta T or temperature rise above ambient
POV - modulating valve
TE - thermal efficiency
TH - thermistor
TIN - temperature of incoming water
Tout - temperature of outgoing water
4

I - GENERAL INFORMATION
This tankless water heater is a high output, high efficiency appliance, which heats the water
continuously as hot water is being drawn for use. Unlike tank type storage water heaters, this water
heater does not store hot water. The burner operates whenever there is a demand for hot water and
is off when the hot water flow stops. Hot water is continuously supplied for any length of time
required as long as the specified flow rates are not exceeded. There is no need to set the
temperature higher than required for sufficient capacity. This water heater has sufficient capacity to
supply several hot water faucets simultaneously. The hot water flow capability will be dependent
upon the temperature of the outlet water selected. Operational feature of this water heater include:
• The burners ignite by direct spark ignition within 3 seconds of detecting minimum
operational water flow. There is no standing pilot.
• variable speed combustion air blower forces the combustion air supply into the burner
compartment.
• Direct vent design uses only outside air for combustion. The venting system is a coaxial
design requiring a single 5 1/4" (13.3 cm) hole through the outside wall or roof. Vent pipe
fittings have internal gaskets for a tight seal to prevent leakage of flue products and
combustion air.
• The burner flame is continuously monitored and modulated to match the heating
requirements of the water flow. Temperature and flow sensors continually monitor the
water flow and outlet water temperature and adjust the burner and combustion air blower
to maintain temperature.
• The Indoor Direct Vent model series have a digital temperature control integrally mounted
to the front panel of the water heater. The outlet water temperature is adjustable from
96-160°F for residential models or 96-180˚F for commercial models. The front panel
temperature control also displays fault codes if the water heater malfunctions to assist with
servicing the water heater. No installation is required for the main temperature control.
• In addition to the main temperature controller, up to two optional bathroom temperature
controls are available on the residential models for setting the water temperature in the
bathroom fixtures up to 120°F.
• The heat exchanger coil is provided with anti-freeze heaters for protection in cold climate
conditions to ambient temperatures as low as -30°F (-34°C). Drain solenoids should be
installed to drain the water heater in the event of a power failure.
(See installation instructions)
Tools equired for Troubleshooting
Multifunction Digital Testmeter with needle point test leads.
Long reach (12") Magnetic Phillips screw driver (#2 Tip)
3/16 llen wrench
Small (pocket size) blade screw driver
Monometer or Magnehelic inches water column gage
5

I - GENERAL INFORMATION (cont.)
HOW TO USE THIS MANUAL
It is intended for this manual to be used by qualified service personnel for the primary purpose of
troubleshooting analysis and repair of this tankless gas fired water heater. Understanding the basic
operation of the "Main Components" and the "Sequence of Operation" sections of this manual will
contribute greatly to your success in the troubleshooting analysis of this product.
Sections of this manual reference general information and specifications. The primary focus is trouble
shooting analysis and repair. The trouble shooting section consists of the following:
• Error Message Table.
Table showing Error Message as displayed on remote control indicating likely fault and
remedy.
• Quick Reference Diagnostics Points Table.
This guide will identify the specific diagnostic point for each component as well as the
correct electrical value for each component.
• Troubleshooting Flow Chart.
The "Trouble Shooting Flow Chart" identifies fault potentials and directs service to
the appropriate diagnostic check points. The check points are identified in the
troubleshooting procedure and are shown on the wiring diagram by means of an
encircled letter with a subscript number.
Example:
This chart will also refer to a page number to reference a pictorial version of the
component analysis as outlined in the "Trouble Shooting Procedure" section of this
manual.
• Trouble Shooting Procedure.
Pictorial procedure including diagnostic points, electrical values and referral to
"Service Procedure" for replacement of faulty components.
• Service Procedure.
Pictorial procedure for removal and replacement of components.
6

I - GENERAL INFORMATION (cont.)
CUT-AWAY ILLUST ATION
7

I - GENERAL INFORMATION (cont.)
SCHEMATIC ILLUST ATION
8

9
II - SPECIFICATIONS - GENE AL
Model type ESIDENTIAL COMME CIAL
Type of appliance Temperature controlled continuous
flow gas hot water system
Operation With / without remote controls, mounted
in kitchen, bathroom, etc.
Exhaust system Direct Vent - Forced combustion
Maximum/Minimum gas rate 180,000 BTU's - 15,000 BTU's Natural Gas
(Input BTU's) 180,000 BTU's - 15,000 BTU's Propane Gas
Hot water capacity, 0.5 to 6.5 GPM
(50°F rise)
Setpoint Temperature Factory setting - 120°F Factory setting - 140°F
(without remote)
Temperature range MC controller : 96 - 160°F
(with remote) BC controller : 96 - 120°F MCC controller : 96-180°F
BSC controller : 96 - 120°F
pproved gas type Natural or Propane - Ensure unit matches
gas supply type.
Installation Indoor Only
Dimensions Height 23 5/8"
Width 13 25/32"
Depth 8 13/16"
Weight 49 Lbs.
Thermal Efficiency rating 0.87 (Propane) 0.82 (Natural)
Noise level 49 dB ( )
Connections Gas supply 3/4" NPT (Male)
Cold water inlet 3/4" NPT (Male)
Hot water outlet 3/4" NPT (Male)
Ignition system Direct electronic ignition
Electrical consumption Operating - 75 watts
Standby - 5.5 watts
nti-frost protection 100 watts
Water temperature control Simulation feedforward and feedback.
Water flow control Water flow sensor, electronic water control
device, and electronic by-pass control device
Recommended Minimum water
supply pressure 20 PSI (recommend 50-80 PSI for maximum performance)
Maximum water supply pressure 150 PSI

II - SPECIFICATIONS - GENE AL
Safety devices ppliance - C 120 Volts - 60Hz. 15 - Dedicated
Remote control DC 12 Volts (Digital)
Flame failure - Flame rod
Boiling protection - 203°F
Remaining flame (OHS) 194°F bi-metal switch
Thermal fuse 264°F
utomatic frost protection - Bimetal sensor & anti-frost heaters
Combustion fan rpm check - Integrated circuit
Over current - Glass fuse (3 amp)
If remote fails or becomes disconnected unit defaults to
100°F with water flowing, this is an anti-scald feature.
Remote control cable Non-polarized two core cable or low voltage thermostat wire
Clearances from combustibles Top of heater 6" (12" min. recomended for service)
Front of heater 6" (24" min. recomended for service)
Sides of heater 2"
Back of heater 0"
Floor 12"
Vent/ ir Intake 0"
10

II - SPECIFICATIONS - COMBUSTION
Item Gas type Natural Propane
Gas consumption Minimum Btu’s 15,000 15,000
Maximum Btu’s 180,000 180,000
Injector Diameter Upper Ø.037 (.95mm) Ø.029 (.75mm)
Inches (mm) Lower Ø.062 (1.6mm) Ø.045 (1.15mm)
Main Burner B3 7-1(Lean and Rich Bunsen Burner)
Main Damper H73-115, Upper: Ø6, Lower: (Not used)
Gas Pressure Minimum supply 6" W.C. 10" W.C.
Supply/Manifold Maximum supply 10.5" W.C. 13.5" W.C.
Low Fire manifold 0.77” W.C 0.93” W.C
High Fire manifold 3.7” W.C 4.2” W.C
11

II - SPECIFICATIONS (cont.)
DIP SWITCH SETTINGS
DANGER
Do not attempt to adjust dip switch settings from there factory default settings.
Doing so will result in damage to unit, property damage, personal injury or death.
Contact Technical Support for information pertaining to dip switch function.
FACTO Y DEFAULT SETTING, ESIDENTIAL UNITS
Natural Gas Propane Gas
Dip Switch Settings: Dip Switch Settings:
(SW1) (SW2) (SW1) (SW2)
#1 = Off #1 = On #1 = Off #1 = Off
#2 = On #2 = Off #2 = On #2 = Off
#3 = Off #3 = Off #3 = Off #3 = Off
#4 = Off #4 = Off #4 = Off #4 = Off
#5 = Off #5 = Off
#6 = Off #6 = Off
#7 = Off #7 = Off
#8 = Off #8 = Off
FACTO Y DEFAULT SETTING, COMME CIAL UNITS
Natural Gas Propane Gas
Dip Switch Settings: Dip Switch Settings:
(SW1) (SW2) (SW1) (SW2)
#1 = Off #1 = On #1 = Off #1 = Off
#2 = On #2 = Off #2 = On #2 = Off
#3 = Off #3 = Off #3 = Off #3 = Off
#4 = Off #4 = On #4 = Off #4 = On
#5 = Off #5 = Off
#6 = Off #6 = Off
#7 = Off #7 = Off
#8 = Off #8 = Off
See page 13 for special dip switch settings base on vent length.
12

II - SPECIFICATIONS (cont.)
DIP SWITCH SETTINGS
Combustion Blower Dip Switch Settings for Vent Length Compensation Under 22 Feet (6.7 m):
To assure optimum efficiency and reduced noise levels, the combustion blower switch has two dip switch
settings. Dip switch number 1 (top dip switch) is shipped from the factory set to the OFF position to
compensate for the maximum vent/air intake length.
Depending upon the vent/air intake length of the installation, Dip Switch Number 1 may need to be adjusted
to compensate for the venting system distance.
When the Total Equivalent Length of vent pipe is more than 22 feet (6.7 m), leave the Dip Switch Number 1 in
the OFF position. This is the factory Dip Switch setting.
When the Total Equivalent Length of vent pipe is 22 feet (6.7 m) or less, Dip Switch Number 1
must be moved to the ON position.
Dip Switch #1 is located in the top row of dip switches, 1 through 8 on the PC board. See the following
diagram to identify the correct switch. If you do not understand the information concerning the Dip Switch
settings or the location of the Dip Switch, contact Bradford White Sales (800-523-2931) or Technical Service
(800-334-3393 x3634) for assistance. Use the following examples and the previous discussion on calculating
the equivalent vent length to determine the correct setting for Dip Switch #1.
Example #1: Dip Switch Settings (Fig. 8)
You have 6 feet (1.82 m) of vent pipe and two 90˚ elbows.
D = 6 + (2 x 6) + (0 x 1.5)
D = 18 feet (5.49 m) of equivalent vent pipe
Dip Switch #1 should be moved to ON position.
Example #2:
You have 15 feet (4.57 m) of vent pipe, one 90˚ elbow, and two 45˚ elbows.
D = 15 + (1 x 6) + (2 x 1.5)
D = 24 feet (7.3 m) of equivalent vent pipe
Leave Dip Switch #1 in the OFF position (factory setting).
WARNING
Do not alter Dip Switch #1 before using the formula and venting charts to determine the equivalent vent
length. ll other dip switches with the exception of Dip Switch #1 shown in the illustration MUST NOT be
altered. Unauthorized adjustments can cause property damage, personal injury, scalding, or death.
13

II - SPECIFICATIONS (cont.)
VENTING TABLE
Venting Table – Examples of Maximum Venting Distances with Various Elbow Combinations
35 Ft. (10.7 m) 1 41 (12.5 m)
29 Ft. (8.8 m) 2 41 (12.5 m)
23 Ft. (7.0 m) 3 41 (12.5 m)
17 Ft. (5.2 m) 4 41 (12.5 m)
33.5 Ft. (10.2 m) 1 1 41 (12.5 m)
32 Ft. (9.8 m) 1 2 41 (12.5 m)
27.5 Ft. (8.4 m) 2 1 41 (12.5 m)
NOTICE
Each 90 degree elbow is equivalent to 6 feet in straight vent pipe length. Each 45 degree elbow is
equivalent to 1.5 feet (0.46 m) in straight pipe length. The total maximum equivalent vent pipe
distance cannot exceed 41 feet (12.5 m) for horizontal venting distance. The maximum vertical height
for through the roof venting cannot exceed 21 feet (6.4 m). condensate collector must be used if
the venting system height is more than 5 feet (1.52 m) above the water heater.
14
Maximum Straight
Pipe Distance
Number of
90 degree elbows
Number of
45 degree elbows
Maximum Total
Equivalent Feet
(meters) of Vent Pipe

III - MAIN COMPONENTS
1. Mechanical Water egulator
The unique water regulator mechanism ensures the hot water is maintained with no noticeable
change to the desired temperature during use, even if water pressure drops due to another tap being
turned on and increasing the demand.
2. Preset Bypass
preset volume of cold water is mixed with water heated in the heat exchanger.
3. Burner
The burner assembly is made up of 16 identical stainless steel
Bunsen burners, secured by an aluminized steel framework.
n aluminum manifold with 32 integral injectors supplies gas
to the burners, and is attached to the front lower cover of the
burner box and gas control assembly.
4. Gas Control Valve
The gas control valve uses four solenoids to fully modulate within four different input ranges to
respond quickly and accurately to changes in water flow rate. The four ranges are as follows: up to
18% of total btu’s (using three burners), up to 33% (using five burners), up to 50% (using eight
burners, and up to 100% (using sixteen burners) This increases the flexibility of the regulator/
modulating valve by supplying gas equally to each burners.
15

III - MAIN COMPONENTS (cont.)
5. Combustion Fan
ir for the combustion is supplied by a centrifugal fan
driven by a DC motor. fter a pre-purge period of 0.2
seconds, the fan speed is controlled by the PCB to
provide the correct volume of air for combustion. The
calculation for the fan speed is based upon incoming
water temperature, water flow and the temperature
selected on the remote controls.
The actual speed of the motor is continuously monitored
by a magnetic pulse sensor.
This sensor emits (4) pulses per rotation of the fan. This is
the fan feedback or confirmation data processed by the PCB.
The fan speed is constantly correcting to provide optimum combustion conditions. In addition, the
fan speed will determine the opening degree of the modulating gas valve. This enables the gas rate to
always match the volume of air for combustion, as well as the input required to heat the water.
6. Water Flow Sensor and Water Flow Control device
Water flow is detected by a turbine/magnetic pulse generating device. Water flows through the
turbine/magnetic sensor providing information to the PCB by generating a pre-determined number of
pulses in proportion to the water flow. These pulses are counted by the PCB – no pulse indicates no
water flow. The frequency of the magnetic pulses increases as the water flow increases, this enables
the PCB to calculate the exact water flow, and determine the water flow in gallons per minute. s
soon as the required water flow is detected, the PCB activates the combustion fan. The combustion
fan speed is monitored by a magnetic pulse sensor. The output from this sensor is processed by the
PCB which opens the gas modulating valve to a degree proportional to the fan speed. See above for
further details on the combustion fan.
The water flow control consists of a plug and barrel valve which is rotated by a motor to increase or
decrease the volume of water passing through the heat exchanger.
Automatic water flow control device.
16

IV - SAFETY DEVICE FUNCTION
Flame Failure
Situated to the right of the burner in the front of the combustion chamber, the flame rod monitors the
combustion process. This sensor monitors the flame intensity, while the PCB compares this signal to
the feed back signal from the combustion fan motor, water flow control, and gas flow through the POV
valve. If any one of the feedback signals are incorrect, the unit will shut off, preventing discharge of
gas to the burner.
Over Heat Protection Device
lso referred to as an Over Heat Switch. This device is fitted to a bend section at the inlet to the heat
exchanger. If the flame remains on to the burner after the tap is closed and the water temperature
inside the heat exchanger reaches 194 ° F, a 12 volt DC bi-metal cut-off switch will shut off the gas
supply to the solenoids.
No Water
Should the incoming water flow become restricted or stop, the water flow sensor will cease to send a
magnetic pulse signal to the PCB, in turn preventing gas to flow into the combustion chamber. If you
have restricted flow, first check to ensure the inline water filter is not clogged.
Thermal Fuse (Non- esettable)
Wrapped around the entire surface of the heat exchanger you will find a thermal fuse. This device
activates in the event of excessive heat echanger temperatures, or the temperature outside the heat
exchanger reaches 264 °F. If the thermal fuse melts, it breaks an electronic circuit which in turn shuts
off the power supply to the gas solenoids, deactivating the unit.
Combustion Fan evolution Check
The combustion fan rpm’s are continually monitored by a magnetic pulse generator connected to the
PCB. If the fan revolutions deviate from the speed required for complete combustion, a signal is sent
to the PCB and the revolutions adjust accordingly. (If not the unit deactivates)
Automatic Frost Protection
When the temperature inside the appliance drops below 37°F , the frost sensing device inside the
appliance activates the anti-frost heaters to prevent the water inside the unit from freezing. The anti-
frost heaters remain ON until the temperature inside the appliance rises to 57°F. There are four (16)
watt anti-frost heaters located at various points throughout the main water flow area of the appliance.
The unit also incorporates the ability to fire for (3) seconds in the event the anti-frost heaters can not
keep the water temperature from dropping below 37°F. This unique feature will heat the water in the
lines inside the appliance back up to 57°F. Both of the above features function as long as the unit
has power and gas. There is an optional freeze protection system that can be added to the unit’s
piping. Refer to the auto drain down diagram in the product installation instructions for instructions
on how to install the optional freeze protection in the event of a power failure.
17

IV - SAFETY DEVICE FUNCTION (cont.)
Over temperature Cut-Off
The temperature of the outgoing hot water is constantly monitored by the water temperature
thermistor located near the outlet of the appliance. If the outgoing water temperature reaches 5 °F
above the preset temperature, the burner will automatically deactivate. The burner will ignite again
when the outgoing hot water temperature falls below the preset temperature.
18

V - SEQUENCE OF OPERATION
The preset temperature is selected at one of the remotes controls (where fitted). Where no remote
control is fitted , the default temperature can be set at 108, 120, 130, 140, 150, 160, 170, or 180°F.
To select one of the above temperatures as your default setting, you MUST obtain written permission
and training (Contact your technical service group).
When the unit is first plugged into 120 volts, the PCB assumes an incoming water temperature of
77°F. This prevents the appliance from starting in “High fire” and producing very hot water the first
time it is used.
The data used to determine the outgoing water temperature, initially, is incoming water flow and the
remote control pre-set temperature.
From the incoming water flow and remote control pre-set temperature data, the CPU is able to
determine a suitable gas rate to initiate appliance operation once a hot water tap opens.
The calculation of temperature rise and water flow is called simulation feed-forward.
The water heater calculates incoming water temperature by subtracting the theoretical temperature
rise from the outgoing hot water temperature to establish the correct gas flow.
When a hot water tap is opened, water begins to flow through the water heater. The turbine in the
water flow sensor begins to revolve. The revolution speed is proportional to the water flow. sensor
located inside the device relays information in the form of magnetic pulses to the main PCB to
determine whether or not water is flowing, and also, the volume of water flowing. When a
predetermined water flow is sensed, the ignition sequence begins.
The combustion fan pre-purges the combustion chamber. rev counter on the combustion fan
indicates the fan rpm to the main PCB. When the pre-purge cycle is completed, the PCB controls the
fan rpm by varying the DC voltage to the fan motor. This maintains the correct air/gas ratio
throughout the time the water heater is in use and ensures proper combustion.
The gas is ignited by direct spark and the flame is sensed by the flame rod. The opening degree of
the modulating valve is determined by the combustion fan speed.
The changeover valve directs gas to one side or both sides of the burner. t the point where the
changeover valve opens or closes the modulating valve is instantly re-adjusted by the PCB to
compensate for the change in the number of burners in use. From the information provided by the
water flow sensor and the water temperature thermistor, the PCB determines how much gas is
required to heat the water to the temperature selected on the remote control.
The PCB is programmed to provide the maximum volume of water possible at a given temperature
rise. s the water flow from the tap is increased, the PCB increases the gas and air flow to the burner.
19

V - SEQUENCE OF OPERATION (cont.)
When the hot water tap is turned off, the water flow sensor stops revolving, and the magnetic pulse
ceases, indicating to the PCB that there is no water flowing, in turn the PCB closes the gas valves. The
combustion fan continues to operate for 65 seconds. This will provide quicker ignition when the tap is
turned on and off in rapid succession, and removes the need for a pre-purge cycle allowing the burner
to re-light immediately when a hot water tap is opened again.
20