Bosch Appliances 125HX NG Water Heater User Manual


 
2 6 720 606 804 (02.10)
Principle of Operation:
When a hot water faucet is opened, the water flow through
the heater causes the gas valve to open. At the same
time the hydro-generator activates the electronics which
sends a spark to the pilot. The flame sensor confirms the
pilot has been lighted and allows the first two burners to
come on. The flame sensor confirms correct activation and
all burners come on. The pilot goes off. 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 activate the water
heater, giving you control over your hot water energy use.
Every time you turn off your hot water faucet, the energy
consumption of your hot water returns to zero.
FEATURES
- Electronic Pilot Ignition driven by hydro-generator
- 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 flame sensor at pilot burner.
- Automatic overheating protection shut-off sensor.
- Flue gas safety device.
- Stainless steel burners with stabilized blue flame.
- Built-in corrosion resistant draft diverter.
- 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.
- On/Off Switch to activate system.
- Red LED indicator flashes with low water pressure.
- Green LED indicator main burner operation.
BOSCH is constantly improving our products, therefore
specifications are subject to change without prior notice.
AquaStar 125HX LP and 125HX NG Specifications
Gas Input max.: 117,000 Btu/hr
min.: 28,000 Btu/hr
Water Connection ½” Thread fitting NPT
H x W x D 29 3/4” x 18 1/4” x 8 3/4"
Vent 5”
CATEGORY I GAS APPLIANCE
Gas Connection 1/2” NPT thread
Min. Water Pressure 18 Psi at 4 GPM
Max. Water Pressure 150 Psi
Shipping Weight 43 LB
Net Weight 40 LB
1.8 GPM at 90
°
rise
3.7 GPM at 45
°
rise
Min. Water Flow 1/2 gal/min
LP GAS Supply Pressure
(before Aquastar regulator) min. 11” W.C.
max. 14” W.C.*
Required LP GAS Pressure at inlet
tap while Aquastar is operating: 10.5” W.C.
LP GAS Burner Manifold pressure while Aquastar is
operating at maximum input: 9.0” W.C.
Natural Gas Supply Pressure min.: 7” W.C.
(before Aquastar regulator) max.: 14” W.C.*
Required Natural Gas Pressure at inlet
tap while Aquastar is operating: 5.7” W.C.
Natural Gas Burner Manifold Pressure while Aquastar is
operating at maximum input: 4.2” W.C.
* Inlet gas pressure before Aquastar regulator must not
exceed this value. Pressure may need to be adjusted for
high altitudes, see page 7.
UNPACKING THE AQUASTAR HEATER
This heater is packed securely. The box includes one water connection fitting, a control knob, a gas pressure regulator,
a pressure relief valve, 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.