AquaStar 125B NG, 125B LP User Manual

INSTALLATION AND OPERATING INSTRUCTIONS FOR AUTOMATIC
INSTANTANEOUS TYPE WATER HEATERS FOR USE WITH NATURAL AND
LIQUEFIED PETROLEUM GAS

MODEL 125B LP and 125B NG (Flow Modulated)

Suitable for water (potable) heating and space heating

Intended for variable flow applications with steady cold water inlet temperatures. For preheated domestic

hot water, install the 125 BS model. For recirculating applications, install the 125 BL model.

WARNING

If the information in this manual is not followed exactly ,
a fire or explosion may result causing property
damage, personal injury or death.

FOR YOUR SAFETY

Do not store or use gasoline or other flammable,
combustible or corrosive vapors and liquids in the
vicinity of this or any other appliance.

WHAT TO DO IF YOU SMELL GAS

- Do not try to light any appliance.

- Do not touch any electrical switch; do not use any

phone in your building.

- Immediately call your gas supplier from a neighbor’s

phone. Follow the gas supplier’s instructions.

- If you cannot reach your gas supplier, call the fire

department.

WARNING: Improper installation, adjustment,

alteration, service or maintenance can cause injury
or property damage. Refer to this manual. For
assistance or additional information consult a
qualified installer, service agency or the gas supplier .
Upon completion of the installation, these instructions
should be handed to the user of the appliance for
future reference.

FEA TURING: Automatic Variable Power Modulating Gas
V alve

- Installation and service must be performed by a
qualified installer, service agency or the gas supplier .

This well engineered, gas water heater has all the fea­tures a water heater should have:

It operates on the principle of heating water instantaneously
“on demand”. When a hot water faucet is opened, cold
water flows through the coils of the heat exchanger in the
Aquastar. This same flow opens the gas valve, and the
burners are ignited by the pilot flame. The heat exchanger
coils absorb the heat generated by the burners and trans­fer heat to the water. When the hot water faucet is shut
off, the gas valve automatically closes and the burners
turn off. Your hot water faucet is an ignition key to turn on
the water heater, giving you control over your hot water
energy use. Each time you turn off your hot water faucet,
you also shut off the water heater .

AquaStar 125B LP and 125B NG Specifications

Gas Input max.: 1 17,000 Btu/hr

min.: 28,000 Btu/hr
Water Connection 1/2” Thread fitting
H x W x D 29 3/4” x 18 1/4” x 8 3/4"
Vent 5”
Gas Connection 1/2” NPT thread
Min. Water Pressure 18 Psi at 4 GPM

FEA TURES

- High Quality Materials for Long Working Life.

- Copper heating coils for endless supply of hot water.

- Burner output proportional to hot water flow demand
for maximum energy efficiency.

- Safety thermocouple at pilot burner.

- Automatic overheating protection shut-off sensor .

- Stainless steel burners with stabilized blue flame.

- Built-in corrosion resistant draft inducer.

- Compact space saver: mounts on a wall with two hooks.

- Easily removable one-piece cover.

- Easy one person installation.

- Adjustable water flow restrictor to ensure that water flow
demand will not exceed the heating capacity of the
heater.

Max. Water Pressure 150 Psi
Shipping Weight 42 LB
Net Weight 39 LB

1.8 GPM at 90° rise

3.7 GPM at 45° rise
Min. Water Flow 1/2 gal/min
LP GAS Supply Pressure inlet. min. 1 1” W.C.

max. 14” W.C.*
LP GAS Manifold pressure 9.0” W.C.**
Natural Gas Pressure inlet min.: 7” W.C.

max.: 14” W.C.*
Natural Gas Manifold Pressure 4.2 W.C.**
* Inlet gas pressure must not exceed this value

** For purposes of input adjustment

- Easy pilot flame lighting with push button piezo ignition.

UNP ACKING THE AQUASTAR HEA TER

This heater is packed securely . The box includes two water connection fittings, a gas pressure regulator, an incandescent
particle tray, two hooks for hanging the heater, this manual, a personal letter, a warranty statement and a warranty
registration card. Do not lose this manual, as there is a charge for replacement. Please complete and return the
enclosed warranty registration card.

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If you are using the AquaStar for combined space heating and potable water heating

schematic diagram below)

, all piping and other components connected to the system must

(see

be suitable for potable water, (b) toxic chemicals such as those commonly used for boiler
treatment to prevent corrosion and freezing must not be introduced into the system, and
(c) if the space heating requires water temperatures higher than those required for do­mestic, potable water, a mixing valve or other similar device must be provided to reduce
scald hazard potential, (d) maximum system water temperature must not exceed 140°F
(60°C). DO NOT CONVERT AN EXISTING, CLOSED HOT WATER HEATING SYSTEM TO A
COMBINA TION SPACE AND POTABLE WATER HEATING SYSTEM USING THE AQUASTAR
OR ANY OTHER HEAT SOURCE.

Open loop potable water and combination space heating system*

* T o be used with a tank, check local codes. May not be permitted in some jurisdictions.

1. Maximum operating temperature of 125B: 140°F

2. Maximum heating capacity: 40°F rise 20°F rise
AquaStar 125B - 80,000 BTU/hr 40,000 BTU/hr

3. System shown is electric storage tank with recirculating supply drawn from the tapping for the lower heating element.

4. Schematic is for illustration and example only and must not be used for actual installation without appropriate

engineering and technical advice from a professional properly licensed in the locality where the installation is made.

GENERAL RULES TO FOLLOW
FOR SAFE OPERA TION

1. You should follow these instructions when you install

your heater. In the United States: The installation must
conform with local codes or, in the absence of local codes,
the National Fuel Gas Code ANSI Z223.1/NFP A 54.
In Canada: The Installation should conform with CGA
B149.(1,2) INSTALLATION CODES and /or local
installation codes.

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2. Carefully plan where you install the heater. Correct
combustion air supply and flue pipe installation are very
important. If not installed correctly , fatal accidents can be
caused by lack of air, carbon monoxide poisoning or fire.

3. The place where you install the heater must have
enough ventilation. The National Fire Codes do not allow
water heater installation in bathrooms, bedrooms or any
occupied rooms normally kept closed. See the section
below on locating the heater.

4. You must vent your heater. See section on Vent Pipe
Connections, Page 5.

5. The appliance must be disconnected from the gas
supply piping system during any pressure testing at
pressures in excess of 1/2 Psig (3.5 kPa).
The appliance must be isolated from the gas supply piping
system by closing its individual manual shutoff valve during
any pressure testing of the gas supply piping system at
test pressures equal to or less than 1/2 Psig (3.5Kpa).
The appliance and its gas connection must be leak tested
before placing the appliance in operation.

Do not obstruct the flow of combustion and ventilation
air to the appliance. If installed near a clothes dryer it is

very important that the dryer be properly vented. Failure
to properly vent a dryer could result in a gradual
accumulation of lint on the water heater fin coils and
burners, leading to a dangerous condition of venting
blockage and poor unsafe combustion.

4. Y our hot water lines should be kept short to save energy .
It is always best to have hot water lines insulated. Having
a floor drain or sink nearby is handy in case you need to
drain water from your heater.

6. Keep water heater area clear and free from
combustibles and flammable liquids. Do not locate the
heater over any material which might burn.

7. Correct gas pressure is critical for the optimum
operation of this heater (see specifications on page 2).
Gas piping must be sized to provide the required pressure
at the maximum output of the heater, while all the other
gas appliances are in operation. Check with your local gas
supplier, and see the section on connecting the gas supply .

8. Should overheating occur or the gas supply fail to shut
off, turn off the gas supply at the manual gas shut off valve
on the gas line.

9. Do not use this appliance if any part has been
underwater. 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
underwater.

PROPER LOCA TION FOR INST ALLING YOUR
HEA TER

Carefully select the location of your new heater. For your
safety and for proper heater operation, you must provide
an abundant supply of combustion air and a proper venting
installation.
The heater may still operate even when improperly vented.
It will, however, be less efficient and could eventually
damage the heater. It could even result in human sickness
or death due to oxygen deprivation and carbon monoxide
poisoning. Follow the guidelines below:

1. Place your heater as close to a vent or chimney as
possible.

2. National building codes require that you do not install
this appliance in bathrooms, bedrooms, unvented closet
or any occupied rooms normally kept closed.

3. Simultaneous operation of other appliances such as
exhaust fans, ventilation systems clothes dryers, fireplaces
or wood stoves could create a vacuum effect in your home
which could cause dangerous combustion by-products to
spill back into your home rather than venting to the outside
through the flue. Confirm that your Aquastar is venting
properly when all these other appliances are running. See
section on venting.

WARNING: The water in this water heater is cold and

always remains cold except for the times that hot water is
being used DO NOT INST ALL IN AN AREA WHERE IT

COULD FREEZE.
This heater is neither designed for nor approved for
outside installation.

WARNING: Flammable materials, gasoline,
pressurized containers, or any other items or articles
that are potentially fire hazards must NOT be placed
on or adjacent to the heater. The appliance area must
be kept free of all combustible materials, gasoline and
other flammable vapors and liquids.

COMBUSTION AIR REQUIREMENTS

Observe the following instructions concerning combustion
air.

Appliances located in unconfined spaces:
a) An unconfined space is one whose volume is greater

than 50 cubic feet per 1000 Btu per hour of the combined
rating of all appliances installed in the space. That would
be 5850 cubic feet for the AquaStar 125B alone.

b) In unconfined spaces in buildings of conventional frame,

masonry, or metal construction, infiltration is normally
adequate to provide air for combustion, ventilation, and
dilution of flue gasses.

Appliances located in confined spaces:) The confined
space must be provided with two permanent openings,
one commencing within 12 inches of the top and one
commencing within 12 inches of the bottom of the
enclosure. Each opening must have a minimum free area
of one square inch per:

- 1000 Btu/hr if all air is taken from inside the building.

- 2000 Btu/hr if all air is taken from the outside by horizontal
ducts.

- 4000 Btu/hr if all air is taken from the outside by direct
openings or vertical ducts.

Louvers, grills and screens have a blocking effect. If the
effective free area is not known, increase the sizes of your
openings by 75% if your louvers are wood and by 30% if
your louvers are metal. Refer to the National Fuel Gas
Code for complete information. In buildings of tight
construction all air should be taken from outside.

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