Bosch AquaStar 125B LPL Installation And Operating Instructions Manual
Automatic instantaneous type water heaters for use with natural and liquefied petroleum gas
Hide thumbs
Also See for AquaStar 125B LPL:
Table of Contents
Advertisement
INSTALLATION AND OPERATING INSTRUCTIONS FOR AUTOMATIC
INSTANTANEOUS TYPE WATER HEATERS FOR USE WITH NATURAL AND
LIQUEFIED PETROLEUM GAS
MODEL 125B LPL and 125B NGL (Non-Modulated)
Certified for space heating in combination with potable water only
Intended for either recirculation to storage or cold water inlet flow that is non-varying.
WARNING
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.
In the Commonwealth of Massachusetts this product
must be installed by a licensed plumber.
Warning: If you do not follow these instructions exactly, a
fire or explosion may result causing property damage,
personal injury or loss of life.
Suitable for heating potable water
Not certified for space heating only.
: Improper installation,
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.
- Installation and service must be performed by a
qualified installer, service agency or the gas supplier.
TABLE OF CONTENTS
Specifications .................................................... Page 2
Rules for safe operation ...................................... Page 4
Locating the Heater ............................................ Page 5
Combustion Air Requirements ............................ Page 5
Mounting the Heater ........................................... Page 6
Venting the Heater ............................................. Page 6
Gas Connections ............................................... Page 7
Water Connections ............................................ Page 9
Safety before lighting the pilot .......................... Page 10
Lighting instructions ......................................... Page 10
About Water Temperature ................................ Page 10
Trouble Shooting ............................................... Page 11
Diagram of AquaStar ......................................... Page 15
Components and Parts List .............................. Page 16
Advertisement
Table of Contents
Related Manuals for Bosch AquaStar 125B LPL
Summary of Contents for Bosch AquaStar 125B LPL
-
Page 1: Table Of Contents
INSTALLATION AND OPERATING INSTRUCTIONS FOR AUTOMATIC INSTANTANEOUS TYPE WATER HEATERS FOR USE WITH NATURAL AND LIQUEFIED PETROLEUM GAS MODEL 125B LPL and 125B NGL (Non-Modulated) Suitable for heating potable water Certified for space heating in combination with potable water only Intended for either recirculation to storage or cold water inlet flow that is non-varying. -
Page 2: Specifications
Aquastar is operating: Natural Gas Burner Manifold pressure while Aquastar is operating at maximum input: * Inlet gas pressure before Aquastar regulator must not exceed this value. Pressure may need to be adjusted for high altitudes, see page 8. - Page 3 COMBUSTIBLE MATERIALS FOR ALCOVE OR CLOSET INSTALLATIONS TOP (A) FRONT (B) BACK SIDES FLOOR (C) VENT DIAMETER * Some local codes require 18” in garage installations AQUASTAR MODEL 125BL SIDE VIEW MODEL 125BL 12 " 4 " 0 " 4 " 12 " *...
-
Page 4: General Rules To Follow For Safe Operation
If you are using the AquaStar for combined space heating and potable water heating (see schematic diagram below), all piping and other components connected to the system must be suitable for potable water, (b) toxic chemicals such as those commonly used for boiler... -
Page 5: Proper Location For Installing Your Heater
A wood stove or furnace can rob the make- up air in the AquaStar’s vent pipe, leaving the cold infiltrating air capable of freezing the cold water in the AquaStar heat exchanger. -
Page 6: Mounting The Heater
In buildings of tight construction all air should be taken from outside. CLEARANCES The Aquastar 125 BL is design certified for installation on a combustible wall and for installation in an alcove or closet with the minimum clearances to combustible and non - combustible construction listed below A. - Page 7 WARNING Note: The burners of an instantaneous “on demand” water heater such as the AquaStar are only on at the time that hot water is actually being used, the vent pipe is therefore cold except for the short durations when hot water is being...
-
Page 8: Gas Piping, Connections And Gas Regulator
Additional Allowance is necessary for an ordinary number of fittings GAS LINE SIZING Follow boxed numbers for piping just one Aquastar 125BL (example: 3/4” B.I. Natural Gas pipe for 30 ft. will handle 152,000 btu’s). For multiple appliances combine the total btu input load and then refer to applicable chart below. -
Page 9: Water Connections
-It is strongly recommended that the Natural Gas pipe be Black Iron pipe the entire distance from the outside meter to the inlet of the Aquastar regulator. 1/2” Black Iron pipe up to 10 feet, 3/4” Black Iron pipe up to 40 feet and 1”... -
Page 10: Safety Before Lighting The Pilot
) and close the gas supply to the heater. INFORMATION ABOUT WATER TEMPERATURE The AquaStar 125B LPL and 125B NGL water heaters produce a 90°F temperature rise at 1.8 gallons per minute. As the flow rate is increased above 1.8, gallons per minute, the temperature will decrease. -
Page 11: Troubleshooting
TROUBLE SHOOTING Air screen filter Introduction The AquaStar 125 BL burners are activated by a water flow valve. Numerous water related problems can cause this water valve to malfunction such as: Insufficient water flow volume to activate the burners at its minimum flow requirement;... - Page 12 3. Water flow rate at hot water tap is too low. Note: The AquaStar models 125BL require 1.8 gallon per minute flow to activate the burners. This is a flow which would fill a quart jar in 8 seconds.
-
Page 13: Water Is Too Hot
AquaStar and the outlet Compare water temperature at outlet of the AquaStar (hold the AquaStar’s outlet pipe with your hand) and at the tap. If these two are very different, check for mixing valve or plumbing crossover (see “MAIN BURNERS WILL NOT IGNITE...”... - Page 14 HOT WATER TEMPERATURE FLUCTUATES 1. Cold water is mixing with the hot water between the AquaStar and the outlet (if not being used with a circulator pump) See #5 under “Burners do Not Ignite When Hot Water Turned On”. 2. Storage in tank (recirculating system) has not fully recovered Storage capacity in tank is inadequate.
-
Page 15: Diagram Of Aquastar
Fig. 10 - Diagram of AquaStar 125 BL Heat exchanger Pilot assembly Burner manifold gas pressure test nipple Pilot gas tubing Main gas burner Gas valve Gas control slide Piezo igniter Location of pressure tap nipple Water valve Gas inlet gas pressure... -
Page 16: Components And Parts List
Fig. 11 - INTERIOR COMPONENTS DIAGRAM AND PARTS LIST... - Page 17 INTERIOR COMPONENTS DIAGRAM Cover Cap cover Water connection gasket Draft divertor Heat exchanger Hot water pipe Cold water pipe Heat exchanger washer Overheat sensor (ECO) Main burner assembly Main burner assembly Pilot burner assembly Pilot filter screen Piezo electrode Pilot orifice “...
-
Page 20: Installation Checklist
Nominal Iron Pipe Size* MAXIMUM LENGTH Semi-rigid Tubing MAXIMUM LENGTH * Flex tubing greatly reduces capacity and, therefore, is not recommended. Minimum Vent Size* and Height Minimum Diameter 5 inches * NOTE: Vent size m ust not be restricted. Installation m ust com ply with national fuel gas code venting requirem ents for a 117,000 Btu Category I appliance and any applicable local codes.
Need help?
Do you have a question about the AquaStar 125B LPL and is the answer not in the manual?
Questions and answers
AQUASTAR 125 BNG -LOW STEADY FLAME WITH MAIN BURNERS, ABOUT 3/4 INCH HIGH. WORKED GOOD FOR 20 YEARS, THANX
A low steady flame about 3/4 inch high on a Bosch AquaStar 125B LPL after 20 years of good performance could be caused by:
1. Insufficient Gas Pressure – Over time, gas supply components may degrade or become obstructed. Checking the gas inlet pressure and consulting a gas service professional is recommended.
2. Clogged Burner or Pilot Assembly – Dirt, debris, or mineral buildup can restrict gas flow to the burner, reducing flame height.
3. Faulty Gas Valve – A malfunctioning gas valve may not deliver the correct amount of gas to the burner.
4. Blocked Heat Exchanger – Mineral deposits inside the heat exchanger can affect combustion and flame quality.
5. Worn-Out Components – After long-term use, parts such as the thermocouple or gas control slide may need replacement.
Inspecting and cleaning the unit, checking gas pressure, and replacing worn components can help restore proper performance.
This answer is automatically generated