Bock Water heaters EZFIT Service manual

WARNING
Improper installation, adjustment, alteration, ser-
vice or maintenance can cause serious injury or
property damage. Refer to this manual. or assis-
tance or additional information, consult a qualified
installer or service agency.
WARNING
Do not install on combustible flooring. Install in ac-
cordance with all local codes. In the absence of
local codes, refer to N PA 54 or ANSI Z21.10.3.
CAUTION
The recommended temperature for normal residen-
tial use is 120° . The dial on the aquastat does not
always reflect the out-coming water temperature
and it could occasionally exceed 120° . Variation in
out-coming temperature could be based on factors
including but not limited to usage patterns and
type of installation. Test water at the tap nearest to
the water heater. See page 11 for measuring the out-
coming water temperature.
WARNING
Hotter water increases the risk of scald injury. Be-
fore adjusting the water temperature setting, read
this instruction manual. Temperatures at which in-
jury occurs vary with the person’s age and the
length of exposure. The slower reaction time of
children, elderly or physically or mentally chal-
lenged persons increases the scalding hazard to
them. It is recommended that lower water tempera-
tures be used where these exposure hazards exist.
Households with small children or invalids may re-
quire a temperature setting less than 120° to pre-
vent accidental contact with hot water. To
produce less than 120°F, use point-of-use tem-
perature limiting devices.
If higher water temperature is needed in part of the
water system, automatic temperature limiting de-
vices must be used on all lines to water taps.
WARNING
Water heater blankets may restrict air flow to the
water heater and cause fire, asphyxiation, personal
injury or death.
THIS MA UAL HAS BEE PREPARED TO ACQUAI T
YOU WITH THE I STALLATIO , OPERATIO , A D
MAI TE A CE OF YOUR WATER HEATER A D TO
PROVIDE IMPORTA T SAFETY I FORMATIO .
Read all instructions thoroughly before attempting
installation or operation of your water heater. Keep
these instructions for future reference.
Local plumbing and electrical codes must be fol-
lowed in the installation of this water heater. In the
absence of a local code use the UNI ORM PLUMB-
ING CODE and the N PA Code. Local codes may su-
persede instructions in this installation manual.
These instructions are a guide for the correct instal-
lation of the water heater. The manufacturer will
not be liable for damages caused by failure to com-
ply with the installation and
operating instructions outlined on the
following pages.
DO NOT use this appliance if any part has been
under water. Immediately call a qualified service
technician to inspect the appliance and to replace
any part of the control system and any gas control
which has been under water.
FAILURE TO FOLLOW THESE I STRUCTIO S OR ALL
APPLICABLE BUILDI G CODES
A D REGULATIO S VOIDS THE WARRA TY O
THIS WATER HEATER.
Warranty, Registration Card and Parts List are included.
Homeowner: Please remember to return the Registration Card!
To the Consumer:
Please read these and all component
instructions and keep for future reference.
To the Installer:
Please attach these instructions
next to the water heater.
Rev 6 6/1623412
– Do not store or use gaso ine or other f ammab e
vapors and iquids in the vicinity of this or any
other app iance.
– WHAT TO DO I YOU SMELL GAS
• Do not try to ight any app iance.
• Do not touch any e ectrica switch; do not use
any phone in your bui ding.
• Immediate y ca your gas supp ier from a neigh-
bor’s phone. Fo ow the gas supp ier’s instructions.
• If you cannot reach your gas suppier, ca the fire
department.
–Insta ation and service must be performed by a
qua ified insta er, service agency or the gas supp ier.
WARNING: If the information in these instructions is not followed exactly, a
fire or explosion may result causing property damage, pesonal injury or death.
Installation and Operation Instructions Manual
Models: EZ 75-135, EZ 80-156, EZ 80-199, EZ 90-199, EZ 100-199
Atmospheric Gas Water Heater

Page 2 Atmospheric Gas
Model
Actual Storage (GAL)
Rated Input (BTU/HR)
B
D
H
Top Inlet Conn. Dia.
Gas Conn. Dia.
Recovery @
100° rise (GPH)
A
C
E
G
Side Wtr. Conn. Dia.
Top Outlet Conn.
Dia.
Shipping Weight (LBS)
EZ 75-135N 67 135,000 130 183 73.25 65.5 26 58.25 20 9 16 6 1.5 1.5 1.5 0.5 410
EZ 80-156N 80 156,000 150 214 73.25 65.5 26 58.5 18 9 16 6 1.5 1.5 1.5 0.5 440
EZ 80-199N 80 199,000 191 255 73 65.25 28 58.5 18 9 16 6 1.5 1.5 1.5 0.5 500
EZ 90-199N 90 199,000 191 263 78 70.25 26 62.75 18 9 16 6 1.5 1.5 1.5 0.5 485
EZ 100-199N 100 199,000 191 271 70.75 63 31.5 54.75 18 9 19 6 1.5 1.5 2 0.5 655
Figure 1: All Models
Table 1: Dimensions
Dimensions (inches)
1st HR. Delivery @
100° rise (GAL)
D
B
A
F
E
COLD
G
C
HOT
H
HOT
COLD
Hand
Hole
Drain
Control
Enclosure
Chamber
Inspection
Port
T&P Relief
Valve
Anode Rod (2)
Flue Damper Draft Hood
SPECIFICATI NS
For LP models change suffix "N" to "LP"
Working Pressure: 150 PSI (1034 kPa)
Test Pressure: 300 PSI (2068 kPa)
Voltage supply: 120V, 60Hz, 1P
For natural gas: anifold pressure = 3.5" W.C. (.87 kPa); Inlet pressure range 5-14" W.C. (1.25 - 1.74 kPa)
For propane gas: anifold pressure = 10" W.C. (2.49 kPa); Inlet pressure range 12-14" W.C. (2.99 - 3.49 kPa)
T&P valve installed
All Bock products meet or exceed current ASHRAE standards.
These products are design certified by UL (Underwriters Laboratories) and meet ANSI Z21.10.3 requirements for operation up to 180°F (82°C).
Approved for use as a an automatic storage tank water heater.
WARNING: Do not install on combustible flooring. Installation should be in accordance with all national and/or local codes. In the absence of local codes, refer
to NFPA 54 or ANSI Z21.10.3
CAUTION: The recommended maximum hot water temperature setting for normal residential use is 120°F (49°C). Bock recommends a
tempering valve or anti-scald valve be installed and used according to the manufacturer's directions to prevent scalding.

Atmospheric Gas Page 3
WHEN Y U RECEIVE Y UR NEW WATER HEATER
Check the new equipment to see if all components are in good condition. If damage is observed
or parts appear to be missing, contact your wholesaler.
WATER HEATER PLACEMENT
CAUTIO
This water heater must be located in an area where leakage of the tank, water line
connections, or the temperature and pressure relief valve will not result in damage to
the area adjacent to the water heater or to lower floors of the structure. When such lo-
cation cannot be avoided, a suitable drain pan must be installed under the water
heater. The drain pan depth must be suitable for draining and collecting water. The
drain pan can be purchased from your plumbing professional. The drain pan must be
piped to an adequate drain and all drain piping must be at least 0.75” in diameter
and pitched for proper drainage. The pan must not restrict combustion air flow.
Locate the heater so it is not subject to physical damage from
moving vehicles or flooding. Do not locate the water heater in a
room where swimming pool chemicals or large quantities of water
softener salt are kept. Installing a water heater in this environ-
ment will result in premature failure of tank and burner compo-
nents due to corrosion caused by these elements
diffusing into the air.
D N T INSTALL THE WATER HEATER N C MBUSTIBLE
FL RING. Place on noncombustible flooring and maintain clear-
ances prescribed by this manufacturer and per code N PA 54. If the
water heater must be located on combustible flooring it must be
raised off the floor with a layer of 4'' concrete block laid so the air
holes are aligned as shown in igure 2. Consult with local code officials before using this
method. Please consult local codes, N PA 54 and/or contact Bock Water Heaters with questions
concerning proper flooring materials. Leave adequate room for periodic maintenance of heater
and burner. The water heater should be placed as near to the chimney as practical in order to
keep vent connector length to a minimum. Consult National uel Gas Code for proper vent con-
figuration.
Minimum clearance to combustible construction is: SIDES 6"; BACK 6"; FR NT 24";
DRAFT H D; 18". The installation of this water heater must conform with local
codes and ordinances. In the absence of local codes, the installation must comply
with the National Fire Protection Association (NFPA 54) Code.
HIGH ALTITUDE
The water heaters covered in this manual are approved for installation at “low” altitudes (0 -
2,000 ft.) and “high” altitudes (2,000 - 7,700 ft.) with natural gas. or LP gas installations at
high altitude, contact Bock Water Heaters.
or natural gas installations at high altitude, the standard (low altitude) orifice can be used at
the preset gas valve manifold pressure (3.5” W.C.). Due to a reduced gas energy content (heat-
ing value) and/or a lower atmospheric pressure at high altitude, there will be a reduction in
input rate at the burner with the standard orifice. or these water heaters, this input rate re-
duction is enough to offset the effects of lower oxygen content in the air at high altitudes up
to 7,700 feet. Refer to the rating plate on the water heater for maximum input ratings at low
altitude (also see Table 1) and high altitudes (given at 5,400 feet and 7,700 feet).
or natural gas installations at altitudes above 7,700 feet, contact Bock Water Heaters.
Figure 2

Page 4 Atmospheric Gas
C MBUSTI N AND VENTILATI N AIR
The water heater must be installed in a location with an adequate air supply for combustion,
ventilation and draft control. Unsafe levels of carbon monoxide (CO), condensation and soot-
ing may result if the room does not have an adequate air supply. See “National uel Gas Code
(N PA 54)” or the discussions of “Unconfined Space” and “Confined Space” below. Poor venti-
lation will also result in hot spots around the heater. Temperatures over 90° near the water
heater generally indicate a lack of ventilation.
UNC NFINED SPACE
Unconfined space is defined by N PA 54 as a space with a volume greater than 50 cubic feet
(during typical use) per 1000 BTUH of the total combined input of all fuel burning appliances
in the space. Rooms leading directly to the installation space through doors that cannot be
closed can be considered part of the space. Exception: Buildings with full vapor barriers, tight
doors and windows or air infiltration rates of less than 0.35 air changes per hour will be consid-
ered a confined space and require additional air supplies.
C NFINED SPACE
Confined space is defined by N PA 54 as a space with a volume less than 50 cubic feet (during
typical use) per 1000 BTUH of the total combined input of all fuel burning appliances in the
space. Buildings or rooms of unusually tight construction are also considered a confined
space. See “Unconfined Space: Exception”.
When installing fuel burning appliances in a confined space, air must be supplied to that
space from either inside or outside of the building as conditions allow.
A. Inside Air Supply: A confined space shall be provided with two permanent openings; one
within 12 inches of the top and one within 12 inches of the bottom of the enclosure. These
openings shall lead directly to room(s) of sufficient volume so that the combined volume of
all the space meets the criteria for unconfined space. Each opening shall have a minimum free
area of 1 square inch per 1000 Btu/hr of the combined total input of all fuel burning appli-
ances in the space. Each opening shall have an area of not less than 100 square inches or a
minimum dimension of not less than 3 inches.
B. utside Air Supply: Confined spaces shall be provided with two permanent openings; one
within 12 inches of the top and one within 12 inches of the bottom of the enclosure. These
openings shall communicate directly, or by ducts, with the outdoors or spaces that
communicate with the outdoors.
1.) Leading directly to the outside or through vertical ducts: Each opening shall have a
minimum free area of one square inch per 4000 Btu/hr of total input rating of all equipment
in the enclosure.
2.) Leading to outside through horizontal ducts: Each opening shall have a minimum free
area of one square inch per 2000 Btu/hr of total input rating of all equipment in the enclosure.
Note: All ducts shall have the same cross sectional area as the free area of each opening to
which they connect. The minimum dimensions of all ducts shall not be less than three inches.
Powered combustion air supplies are also commercially available and may be used.
L UVERS & GRILLES
In calculating the free area of an opening, consideration must be given to the blocking effects
of louvers or grilles protecting the opening. Any screens used must be no finer than 1⁄4inch
mesh. If the free area of a louver or grille is known, this should be used in calculating the size
of opening required. If free area is unknown, it may be assumed that wood louvers will have
20 to 25% free area and metal louvers and grilles will have 60 to 75% free area. Louvers and
grilles should be fixed in the open position or interlocked with the equipment so that they
open automatically during equipment operation.

Atmospheric Gas Page 5
VENTING
The water heater shall be located as close to the chimney as practical. Long lateral runs will
result in intermittent combustion problems and unsafe operating conditions. Total vent
height should be a minimum of 6 feet. Shorter vent heights could result in unstable draft and
nuisance lock outs.
The venting system should be sized according to National uel Gas Code: N PA 54/ANSI
Z223.1 (most recent edition) using the “Natural” column. If you do not have a copy of this
code one can be obtained at www.N PA.org for a nominal fee. Copies of the N PA venting ta-
bles are also reprinted in the Bock Engineering Manual available from your Bock Representa-
tive or download from www.bockwaterheaters.com. Note: Do not reduce vent size more than
one size smaller than the vent connector supplied with the heater. If vent size must be reduced
one size, use full size vent connectors on the vent hood and reduce vent size as far from the
water heater as practical. B vent, L vent or multi-fuel venting may be used. Vent tables sup-
plied by the vent manufacturer may also be used in sizing the vent system.
Venting system must be capable of producing –0.02" WC (inches of water column) draft mini-
mum. If draft of –0.02" WC cannot be produced with an existing vent system, a draft inducer
may be required. Installations common vented with large vent hood equipped appliances such
as heating boilers may require vent dampers on the heating boiler connectors for proper vent
operation during no-heating season.
Check the building for items that can cause severe negative pressure problems such as large
exhaust fans. If these devices are installed in the same building check for their effect on draft
and combustion. All fuel burning appliances must be isolated from the effects of these devices
to operate properly. ailure to address this issue will result in unsafe operation and shorten
appliance life spans.
Your Bock water heater may also be operated with a power venter. The power venter must be
properly sized and adjusted to provide proper draft. Power venter wiring must turn on the
power venter on a call for heat and must prove venter operation before allowing the burner to
start. Refer to the power venter instructions for proper wiring and adjustment procedures.
Power vent terminal clearances must comply with local codes or the latest edition of N PA
54/ANSI Z223.1 or CSA B149. See igure 3 and Table 2 for required clearances.
Figure 3: Power Vent Terminal Clearances

Page 6 Atmospheric Gas
VENTING (cont.)
DRAFT H D, DAMPER AND REDUCER C LLAR ASSEMBLY
Your Bock water heater is equipped with a vent hood, reducer collar and an electronic flue
damper. This system has been specifically designed to give your Bock water heater exceptional
reliability and safe operation. The draft hood, damper and reducer collar must be assembled
and installed as shown in Figure 3. Note: Substitution, elimination or relocation of any
of these components will result in unsafe operation and void the warranty of your
water heater. Refer to the instruction sheet provided with the damper for more detail on
damper operation and troubleshooting.
1. Align the hole in the rear of the damper base with
the hole in the tab on the reducer collar. Insert the
smooth end of the damper base into the reducer collar
and secure in place with a sheet metal screw (provided)
through the damper base and collar tab.
2. With the damper arm oriented toward the front of
the heater, slide the reducer collar squarely over the
flue. Make certain that the arm does not interfere with
hot water piping and that the damper harness can safe-
ly reach the damper.
3. Attach damper harness (4 pin connector) to the damper.
4. Install the draft hood on top of the damper assembly. The draft hood should fit snugly over
the corrugated section on top of the damper.
ollowing installation on the water heater, make sure the draft hood and damper assembly are
clear of obstructions. Clear visibility to this area is required for determination of damper posi-
tion. A clearance of 24” from the front of the damper is required for access for service.
Figure 4
Table 2: Power Vent Terminal Clearances
36 inches (91 cm)
36 inches (91 cm)

Atmospheric Gas Page 7
C NNECT WATER PIPING
This water heater incorporates fittings that contain a nonmetallic lining. Do not apply heat to
these fittings when making sweat connections to the heater. Sweat tubing to an adapter before
securing adapter to any fittings on the water heater.
The Bock ez IT series includes hot outlet and cold inlet water connections on the top and side of
the water heater. Choose a cold inlet and hot outlet combination that best suits the installation.
Install dielectric unions and shut off valves on both hot and cold water lines. Recirculation/re-
turn lines can be plumbed to a cold water inlet, if necessary.
These models are equipped with an inlet flow diverter (side cold inlet) installed in the tank.
Heaters equipped with this diverter are labeled with a decal next to the inlet (shown to the
left). The purpose of this diverter is to help keep the tank bottom free of sediment by aiding
tank flushing. The index line on the diverter nipple must be aligned with the arrow on the
decal (left) to function properly. Do not allow the divert-
er to rotate out of position when tightening the inlet fit-
tings.
An approved pressure and temperature relief valve is fac-
tory installed in the opening provided in the upper right-
hand side of the water heater. or safe operation of the
water heater, the relief valve must not be removed from
this location or plugged. When replacing the relief valve,
the new valve must have a rated discharge capacity equal
to or greater than the rated input of the water heater. It must also have a maximum tempera-
ture rating of 210° and maximum pressure must not exceed 150 psi. Pipe the T&P valve outlet
to within 6" of the floor or to a floor drain with a free flowing drain pipe. No shut off valve
should be installed in the line between the relief valve and the drain. The area around the water
heater and the T&P piping should be protected against possible water damage caused by the
functioning of the T&P valve.
CAUTIO
Scalding injury and/or water damage can occur from either the manual lifting of the lever or
the normal operation of the T&P valve if it is not piped to a proper drain. If the valve fails to
flow water or reseat, call your plumber.
Check incoming water line for backflow preventers or water pressure reducing valves, as these
may cause pressure to build up in the water heater and result in tank failure. If this water
heater is installed in a closed system or if backflow preventers and pressure regulators are
installed, a properly sized expansion tank must be installed.
Note: Do not try to heat hard water as this will drastically reduce heater life. Install a water
softener or other scale reducing water treatment system if the water heater is being installed in
a hard water area (water hardness higher than seven grains).
If this heater is used for water (potable) heating and space heating, the following requirements apply:
- Piping and components connected to the water heater for the space heating application must
be suitable for use with potable water.
- Toxic chemicals, such as used for boiler treatment, shall not be introduced into the potable
water used for space heating.
- A water heater which will be used to supply potable water shall not be connected to any
heating system or component(s) previously used with a non-potable water heating appliance.
- If the space heating requires water at a temperature higher than required for other uses, a
tempering valve shall be installed to reduce the water temperature for those uses in order to
lessen scald hazard potential.
- This water heater cannot be used for space heating applications only.
- Space heating piping connections shall be made to the free Hot/Cold connections on the
water heater. Two sets of Hot/Cold connections are supplied.

Page 8 Atmospheric Gas
TEMPERATURE C NTR L M DULE
Your Bock water heater is equipped with an electronic temperature control with many ad-
vanced features. The temperature control is located in the control enclosure along with the
burner ignition module. This temperature control uses two probes to measure the average
water temperature in the tank. One probe located near the tank bottom senses temperature
and has a two wire harness. The other probe located near the top of the heater contains a tem-
perature sensor and a high limit electronic cut out (ECO). This control also has 4 LED’s that in-
dicate the operating condition. A green LED indicates that power is being delivered to the
control. A series of red LED’s indicates a call for heat, a high limit (ECO) cut out and reset sta-
tus. The control requires a manual reset if the water temperature exceeds the ECO setting of
200° . A gray button in the upper right hand corner of the control above the power supply is
the manual reset. Temperature is adjusted with a large black dial on the face of the control.
Temperature settings are marked in white on the dial. The temperature range of this control is
120° to 180° .
C NNECT THE ELECTRICITY
Your Bock water heater uses 120VAC, 60Hz line voltage. Total current load is less than 12
amps. This appliance must be electrically grounded and comply with all local codes. In the ab-
sence of local codes all wiring must conform with ANSI/N PA 70—most recent edition. Electri-
cal power to this appliance should be supplied through a fused disconnect switch located on
or near the water heater. A metal junction box is located in the control enclosure (with a pre-
wired power cord) and may also serve as a location for a fused disconnect switch. Observe cor-
rect polarity when connecting this water heater to the power supply. Line voltage is supplied
to the temperature control module from the junction box. The temperature control module
supplies 24VAC power to the gas valve, burner control module and flue damper. See igures 5
and 6 for wiring diagrams.
WIRING DIAGRAM
Figure 5: Connection Diagram Figure 6: Schematic (Ladder) Diagram

Atmospheric Gas Page 9
C NNECT THE GAS LINE
CAUTIO
Do not use this water heater with any gas other than the type listed on the rating label.
Check the rating label on the front of the water heater and make sure the gas to be used
matches the gas stated on the rating label. Consult your local gas company or Bock Water
Heaters with any questions.
A manual gas valve, a union, and a sediment trap should all be provided in front of the gas
valve. All gas piping must conform to local codes and/or the National uel Gas Code; ANSI
223.1/N PA 54 (Latest Edition).
Supply piping should be sized according to the charts found in the National uel Gas Code
for natural gas applications.
Note: When sizing the gas piping to the heater, make sure that the pressure at the valve is
sufficient when all other appliances are operating. Undersized gas piping will reduce water
heater performance and life as well as result in nuisance lockouts. Also verify that the gas ser-
vice and meter are sized properly for the load.
Gas piping should be carried oversize, i.e.: 3⁄4inch or 1 inch or larger for 1⁄2inch valve to
within 2 feet of the valve itself. This sustains pressure at the valve during start-up to prevent
flashbacks caused by momentary pressure loss. or natural gas, 5" W.C. pressure must be main-
tained upstream of the gas valve during operation. or LP gas, a minimum of 12" W.C. must be
maintained upstream of the gas valve. A 1⁄8inch NPT pipe connection should be installed up-
stream of the manual shut-off valve to check incoming gas pressure.
During pressure testing of the gas supply piping, close the manual gas shut-off valve to the
water heater. Test pressure shall not exceed 1⁄2PSIG (14" W.C). The gas valve is only rated for
1⁄2PSIG. To test at pressure greater than 1⁄2PSIG, close the manual shut-off valve and discon-
nect the gas operating valve.
Turn on gas and inspect piping for leaks by “painting” each joint with soap and checking for
bubbles. Do not use open flame. The pipe thread compound that is used on gas piping must be
of the type resistant to propane gas. Do not use teflon tape on gas piping. Note: or high alti-
tude applications (above 2000 feet) contact Bock Water Heaters.
WATER SYSTEM PERATI N
Partially open all hot water faucets. Open cold water inlet valve to the water heater. Close hot
water faucets as they deliver water that is free of air. Start at lowest point in the building and
work upwards. Inspect for leaks.

Page 10 Atmospheric Gas
GAS SYSTEM PERATI N
Turn off all electrical power to the water heater. Verify that the gas main is open and gas
pressure does not exceed 14" W.C. in the gas line. Gas pressures over 14" W.C. will damage the
gas valve. If gas pressure is under 14" W.C. open the gas cock and bleed the gas lines until all
air is purged from the line. Make certain the area is well ventilated while performing this
step. Check for any gas leaks on the burner piping. Prior to initial burner operation, check
that inlet gas pressure is in the correct operating range (5-14" W.C. for natural gas; 12-14"
W.C. for propane gas).
1. Set the thermostat to the lowest setting.
2. Turn off all electrical power to the appliance.
3. DO NOT attempt to light the burner by hand.
4. Turn gas control knob clockwise to “O ”. D N T F RCE.
5. Wait for five (5) minutes to clear out any gas. If you smell gas, ST P!
WAR I G
LP gas/propane gas is heavier than air and will remain at floor level in the occurrence of a
leak. Spaces below ground level will serve as areas for accumulation of leaking gas. Smell
around the entire appliance area for gas before lighting. Be sure to smell near the floor.
IF YOU SMELL GAS:
• Clear the room, building, or area of all occupants and do not re-enter the area until the
space has been determined to be safe.
• Use all practical means to eliminate sources of ignition. DO OT OPERATE THE APPLIA CE.
If possible, cut off all electric circuits at a remote source to eliminate operation of automatic
switches in the area. Do not use any telephone in the area of the gas leak.
• Call your gas supplier from a telephone remote from the area of the leak. Follow the gas
supplier’s instructions.
WAR I G
DO OT ATTEMPT TO LIGHT A Y GAS APPLIA CE IF YOU ARE U CERTAI OF THE FOLLOWI G:
• LP gas/propane gas and natural gas have an odorant added by the gas supplier that aids
in detection of the gas.
• This odor should be recognizable as a “sulfur” or “rotten egg” smell.
• If you have a diminished sense of smell or are unsure of the presence of gas, contact your
gas supplier from a telephone in another building.
• Consult with your gas supplier about the availability of gas detectors.
If you do not smell gas or the leak is corrected, go to next step.
6. Turn gas control knob counterclockwise to “ON”.
7. Turn on all electric power to appliance.
8. Set thermostat to desired setting.
9. If the appliance will not operate, follow the instructions on
page 11 “To Turn ff Gas To Appliance” and call your
service technician or gas supplier.
Verify gas inlet and manifold pressure. or natural gas, manifold
gas pressure should be 3.5" W.C. and inlet pressure should be between 5-14" W.C. or propane
gas, manifold pressure should be 10" W.C. and inlet pressure should be between 12-14" W.C.
Your Bock water heater uses a built-in pressure regulator and fixed burner orifice so ordinarily
no gas rate adjustments are required.
Figure 7: Gas Valve

Atmospheric Gas Page 11
T TURN FF GAS T APPLIANCE
1. Set thermostat to lowest setting.
2. Turn off all electric power to appliance if service is to be performed.
3. Push in gas control knob slightly and turn clockwise to “O ”. D N T F RCE.
4. Close main gas valve.
INSPECT THE INSTALLATI N AND ADJUST THE C NTR LS
The thermostat has been adjusted to 120° at the factory. Wait until thermostat has shut off
gas to the main burner. Wait 30 seconds following shut-off of gas, then set thermostat to the
highest temperature. The main burner should relight. Set thermostat to the lowest tempera-
ture; the main burner should go out. The thermostat should be adjusted to the minimum
setting that will meet the hot water needs of the homeowner or commercial application.
CAUTIO
There is a scald potential if the thermostat is set too high. The recommended temperature
setting for normal residential use is 120°F. If higher temperature settings are needed for
combined appliance applications or commercial use, an automatic tempering valve
must be installed on all domestic hot water lines. Should overheating occur, or the gas
supply fail to shut off, turn off the electricity to the water heater.
MEASURING THE UTC MING WATER TEMPERATURE
The thermostat is factory set at 120° for domestic use. It is the responsibility of the building
owner to verify that the installer follows the recommended quantitative testing for measuring
the out- coming water temperature. To make sure that the system works properly after installa-
tion and in the future, it is recommended that the heater’s performance be measured and mon-
itored. Run water out of the tap nearest the heater until it comes out warm. Using a calibrated
thermometer, take a measurement. If the water is not at a suitable temperature for the installa-
tion, have a qualified service person adjust the temperature control. Contact Bock for further
information if needed.
This log (or a similar one) should be filled out as follows:
WAR I G
Hydrogen gas can be produced in a hot water system served by a heater that has not been
used for a long period of time (generally two weeks or more). Hydrogen gas is extremely
flammable. To reduce the risk of injury, open the hot water faucet at the highest location in
the house for several minutes before using any electrical appliance connected to the hot
water system. If hydrogen is present, there may be an unusual sound similar to air escaping
through the pipe as the water begins to flow. Do not smoke or allow an open flame near the
faucet at the time it is open.
Date Time Person running test Set temp °F Outlet temp °F

Page 12 Atmospheric Gas
MAINTENANCE
Notice to the wner: If you are having a mechanical problem with your water heater, con-
tact your service company or installer.
Lime and Sediment: A program of regular maintenance should be established to keep your
water heater operating at peak efficiency. Important: The tank can fail prematurely from
an accumulation of lime and sediment in the bottom, excessive pressure and/or
corrosion. Prevention of these damaging factors will extend the life of your water heater
appreciably.
All Bock atmospheric gas water heaters have hand holes that permit the visual inspection of
the tank interior for lime. The hand hole is large enough to reach in and loosen such deposits
by brushing or scraping. A commercial lime dissolving chemical can also be employed. The
loosened residue can be flushed away through the hand hole or drain.
These accumulations can be controlled to an extent by softening the water or using other scale
reducing water treatment systems. The tank should be inspected every six months: Turn off
gas and electrical power, drain, remove the hand hole cover and make a visual check of the
tank interior. If lime (or sediment) has accumulated, remove with a commercial lime dissolv-
ing chemical or scrape loose the deposit and flush it away through the hand hole or drain.
Excessive pressure is controlled by the pressure relief valve. Water expands when heated and
the extra volume must have a place to go. If water cannot expand into the cold water line
because of a check valve or pressure regulator, pressure builds as the water heats. The pressure
relief valve opens and dumps the extra water. If the relief valve is faulty, or none has been
installed, the tank can fail due to excessive pressure. Open the relief valve at least once a
year to make sure the seat is not stuck.
CAUTIO
Before opening the relief valve, be certain that the discharge line directs the flow of
water to the drain. Stand away from the outlet to avoid contact with the water.
Anode rods are installed in the head of the tank to help prevent corrosion. When inspecting
the tank interior for lime or sediment accumulations, also inspect the condition of the anode
rods. When the diameter of either rod has eroded to about 2⁄3of its original diameter
(original=0.90”), it must be replaced.
Electrolysis can be reduced by installing dielectric connections on the cold water inlet and hot
water outlet.
The vent system should be checked at least once a year for damage and/or blockage. Also
check for correct draft and damper operation.
If the water heater is to be shut off during cold weather, the tank and water lines should be
drained to prevent freezing.
The water heater warranty will be invalid if the tank fails due to excessive pressure, the accu-
mulation of lime or sediment, corrosion, or freezing. The warranty explicitly documents
further causes of invalidation.
If necessary, the water heater flue may be cleaned with a brush or a flexible wire. Before pro-
ceeding:
• Turn the gas valve to O .
• Wait at least 5 minutes for the combustion chamber and flue to cool.
• Use a brush or flexible wire to clean the flue. This can be done through the top of the flue.
It is not necessary to remove the burner or baffle.
• Slide the flexible wire or brush down the flue at the base of each row of fins. This should
knock any rust flakes into the combustion chamber for removal.
WAR I G
If the flue is blocked with soot this indicates serious combustion problems related to the
building and/or installation. These must be addressed before placing the water heater back
in operation.
• Vacuum or sweep out any sediment collected in the combustion chamber before restarting
the heater. This can be done through the chamber inspection port.

Atmospheric Gas Page 13
CHAMBER INSPECTI N P RT
The chamber inspection port is located near the bottom of your Bock water heater. If access to
the combustion chamber for flame inspection or maintenance is necessary, following these
steps:
• Wear protective handwear. Areas around the combustion
chamber may be hot after operation of the appliance.
• Remove the sheet metal screws at the right and left sides of the
sheet metal door.
• Swing the door clockwise or counterclockwise on the rivet to
expose the inspection port plug. Use needle-nose pliers to pinch
and pull the plug from position. Two pinch points are located
on the front-center of the plug.
• ollowing inspection of the flame or maintenance, replace the plug and sheet metal screws
to their initial locations.
Inspecting the burner flames: The burner flame should be visually inspected at least once a
year to determine if the flame has altered in appearance. Changes in the flame shape and
color can indicate the need for service.
The burner flame should be steady and appear blue on the burner face with well defined yel-
low and orange tips. lame shape should be similar to that shown in igure 8. A flame that
does not burn upwards and/or is mostly yellow indicates a draft and combustion problem. If
this type of flame is observed, call a qualified service agency.
Products of combustion need to be checked with instruments. High levels of CO could indi-
cate a problem with the heater such as a blocked flue or other installation related problems.
Inspecting the ignitor/flame rod assembly: The burner ignitor/flame rod assembly is com-
prised of an ignitor/flame rod and a ground rod. This assembly should be visually inspected
at least once a year. Disconnect power to the water heater and open the chamber inspection
port. A flashlight may be necessary. Visually inspect the two ignitor assembly rods for black
soot/carbon buildup. If the rod(s) exhibit carbon buildup, future ignition and flame sensing
problems may arise. Call a qualified service agency to clean these components.
TR UBLESH TING
Burner will not light:
1. ollow instructions under “Gas System peration”.
2. Check temperature control reset status. LED’s indicate control status. Reset the control by
pressing the reset button. Refer to “Temperature Control Module” section.
3. Check 3 amp fuse on temperature control module.
4. Verify that the temperature control is calling for heat. If the tank is cold but control is not
calling for heat, check resistance of the temperature sensors. Resistance of temperature
sensors should be, for example, in the range of 19.9 kohms - 3.8 kohms for temperatures
between 50 - 120 . Check the ECO for electrical continuity (resistance should be 0 ohms).
5. Check voltage to burner control. 24VAC should be supplied to the burner control when a
“call for heat” is present at the temperature control.
CAUTIO
Label all wires prior to disconnection when servicing controls. Wiring errors can cause
improper and dangerous operation. Verify proper operation after servicing.
Figure 8: Main Burner Flame

Page 14 Atmospheric Gas
6. The burner control contains an LED that flashes a fault code for certain events. If the red
LED is flashing, refer to Table 3 for flash code descriptions.
7. Verify that power is supplied to the damper and that
it is free to rotate. See the instruction sheets included
with the damper for more detailed troubleshooting.
8. Check for spark at the ignitor. If no spark check wire
condition. If spark is present but burner does not
light, turn off power to water heater. Remove burner
assembly from water heater and check spark gap po-
sition. igure 9 shows the proper position of the
spark gap. The gap needs to be directly above and
midway between the inner and outer ribbons at the
end of the burner tube.
9. Check wiring connections to the gas valve. Verify that 24VAC is supplied to the gas valve. If
burner lights and immediately shuts off check the gas valve ground and ground wire. If gas
valve is not opening, replace valve and recheck gas supply pressure.
10. Inspect the rollout switch (located at the bottom of the control enclosure). If switch opened
due to flame rollout, call a qualified service agency and do not resume operation of the
water heater.
If flame rollout did not occur, turn off power to water heater and check for electrical conti-
nuity across wire terminals. Press the button at the top of the device to reset the switch.
Table 2: Fenwal control flash codes
If system fails to light on next three trials for ignition,
check gas supply, ignition cable, burner ground
connection, check for spark at igniter, check for proper
position of spark gap above burner ribbon,
contamination of spark/sense rod.
Ignition lockout3 Flashes
Red LED
Flash Code Indicates Recommended Service Action
Reset by cycling "Call for Heat" or reseting power to
water heater. If error repeats, replace the control.
Steady ON Internal control failure
Figure 9: Spark Gap Position







BURNER C NVERSI N KIT
The Bock ez IT series is designed for use with natural gas or LP gas. Do not operate this water
heater with a gas other than the type listed on the rating label. A burner conversion kit shall
be purchased and installed in the event that a fuel change from natural to LP gas is desired.
The conversion kit will include a complete burner, rating label that indicates the new fuel
type, and detailed instructions. Please contact your sales representative or Bock Water Heaters
with any questions.
Table 3: Fenwal control flash codes
WARNING
Conditions that cause the rollout switch to open could result in death or serious
injury. A qualified agency shall inspect the water heater before it is put back
into service.
䊱
!

Atmospheric Gas Page 15
PARTS LIST
2
1
3
5
4
20
21
21
10
789
11
12
13 14
15
6
17
19 18
16
Table 4: ezFIT Parts
Figure 10: ezFIT Parts
1 Draft Hood 12 Temp. Sensor (lower)
2 Flue Damper 13 Inspection Port Plug
3 Reducer Collar 14 Inspection Port Door
4 Hot Outlet Nipple (Top) 15 Cold Inlet (flow diverter) Nipple (side)
5 Flue Baffle 16 Wire Harness (Temp. Control/Damper)
6 Temp. Sensor & ECO (upper) 17 Hot Outlet Nipple (side)
7 Hand Hole Cover (jacket) 18 T&P Relief Valve
8 Hand Hole Cover 19 Pipe Nipple (for T&P Valve)
9 Hand Hole Gasket 20 Dip Tube
10 Wire Harness (Gas Valve) 21 Anode Rods
11 Drain Valve
Part Description

Page 16
Table 5: ezFIT Control Enclosure and Burner Parts
Part Description




  



Figure 11: ezFIT Control Enclosure Parts






Figure 12: ezFIT Burner Parts
PARTS LIST
22 Power Cord 29 Gas alve (Natural or LP)
23 Temperature Control 30 Ignitor & Flame Rod Assembly
24 Burner Ignition Module 31 Flame Spreader
25 Control Enclosure Cover 32 Burner Tube
26 Control Enclosure Base 33 Ignition Cable
27 Junction Box 34 Burner Orifice
28 Rollout Switch

Atmospheric Gas Page 17
LIMITED WARRANTY F R GAS-FIRED WATER HEATER
Bock Water Heaters, Inc.
110 S. Dickinson Street
Madison, WI 53703
hone: 608-257-2225
WHAT D ES THIS LIMITED WARRANTY C VER?
This limited warranty applies only to the original consumer purchaser.
General Defects and Malfunctions: This warranty covers defections and malfunctions in your
new water heater for a period of one year from the original installation date. We will repair or
replace, at our option, any defective or malfunctioning component of the water heater. This
limited warranty will terminate if you sell or otherwise transfer the water heater, or the water
heater is installed at a location different from its original installation location.
Tank and Heat Exchanger: We also warrant that the tank and heat exchanger will not leak due
to defective materials or workmanship for five years from the date of original installation or
from date of manufacture in the event the Limited Warranty Registration Card was not com-
pleted and returned to manufacturer. If the tank and heat exchanger is leaking and we have
verified that the leak is due to a defect in materials and workmanship, we will replace the
tank with a tank that is the nearest Bock model available at the time of replacement. If a re-
placement tank is provided, it will remain warranted under this section as if it were the origi-
nal tank. For example, if we send you a replacement tank under this limited warranty two
years after the original installation date, then the replacement tank will remain warranted for
the remaining three years after the original installation date.
H W D Y U GET SERVICE UNDER THE LIMITED WARRANTY?
In order for the warranty period to begin on the date of installation, you must return the war-
ranty registration card attached below within 30 days of purchasing the water heater. You may
also register your water heater online at www.bockwaterheaters.com. You must have a copy of
the original sales receipt at the time you request service. Failure to return the warranty regis-
tration card and provide a copy of the sales receipt will result in the warranty period begin-
ning from the date of manufacture.
To get service under this limited warranty you should contact either the dealer or installer. If
dealer or installer is unknown you can contact us via e-mail at
[email protected] or call us Monday through Friday between the hours of
8 o’clock a.m. to 5 o’clock p.m. Central Time at the following number: 1-608-257-2225.
You can also write us at the following address:
Bock Water Heaters, Inc.
Warranty Support Group
110 S. Dickinson Street
Madison, WI 53703

Page 18 Atmospheric Gas
WHAT D ES THIS LIMITED WARRANTY N T C VER?
This limited warranty does not cover water heaters that are or were:
• Incorrectly installed, especially where the installation violates state or local
plumbing, housing or building codes.
• Operated at inappropriate settings, excessive pressures or temperatures.
• Exposed to adverse local conditions and specifically sediment or lime
precipitation in the tank or corrosive elements in the atmosphere or unacceptable
water quality.
• Installed outside the United States or Canada.
• Accidentally damaged.
Also, we will not cover the following charges, costs and losses:
• Any freight or delivery charges.
• Any removal or installation charges.
• Charges to return the water heater or part to the manufacturer.
• Water damage, loss or damage to property, inconvenience or loss of use.
WHAT WILL V ID THE LIMITED WARRANTY?
If you do any of the following, you will void this limited warranty:
• Fail to retain an original copy of your sales receipt.
• Fail to retain the actual rating plate from the water heater.
• Alter or remove the serial number.
• Transfer or sell the water heater.
• Remove the water heater from its original location and install it somewhere else.
• Fail to follow the care and maintenance instructions provided with the water
heater.
• Remove the anode rods.
• Fail to inspect and replace the anode rods (you must retain and present your paid
receipts as proof of anode rod replacement).
H W D ES STATE LAW RELATE T THIS LIMITED WARRANTY?
This is a limited warranty. WE MAKE NO OTHER EX RESS WARRANTIES WITH RES ECT TO
THIS WATER HEATER. We will not assume, nor authorize any person to assume for us any
other liability in connection with the sale or operation of this water heater. ANY IM LIED
WARRANTIES, INCLUDING MECHANTABILITY OR FITNESS FOR A ARTICULAR A LICA-
TION, IM OSED ON THIS SALE UNDER THE LAWS OF THE STATE OF SALE ARE LIMITED TO
ONE YEAR. This warranty gives you specific legal rights, and you may also have other rights
which vary from state to state. Some states do not allow limitations on how long an implied
warranty lasts, so the above limitation may not apply to you.
WE WILL NOT BE RES ONSIBLE FOR WATER DAMAGE, LOSS OF USE OF THE UNIT, INCON-
VENIENCE, LOSS OR DAMAGE TO ERSONAL RO ERTY, WHETHER DIRECT OR INDIRECT,
AND WHETHER ARISING IN CONTACT OR TORT. Some states do not allow the exclusion of
incidental or consequential damages, so the above exclusion may not apply to you.
Bock Water Heaters, Inc. • 110 South Dickinson Street • Madison, WI 53703
Telephone [phone] • Fax [phone]

Atmospheric Gas Page 19

Page 20 Atmospheric Gas