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This well engineered, gas water heater has been spe-
cially designed to operate with incoming pre-heated
water:
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 trans-
fer 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. On the Aquastar “S”
model, if the incoming water is colder than the thermostat
setting of the heater, the burners will ignite to heat the
water in order to boost it and maintain it at the tempera-
ture setting. If the incoming water has been pre-heated,
(ie) solar, and this water temperature is warm then the
the burners will modulate down accordingly, or shut down
completely if the temperature is as hot or hotter than the
heater thermostat setting. The Aquastar 125 BS is the
perfect backup to a solar hot water system.
FEATURES
- 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.
- Automatic Thermostatic Control for steady hot water
temperature
- Input BTU’s modulate to zero to prevent overheating of
water from pre-heat source
- 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.
- Easy pilot flame lighting with push button piezo ignition.
AquaStar 125B LPS and 125B NGS Specifications
Gas Input max.: 117,000 Btu/hr
min.: 23,400 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
Max. Water Pressure 150 Psi
Shipping Weight 44 LB
Net Weight 42 LB
1.8 GPM at 90o rise
3.7 GPM at 45o rise
Min. Water Flow 1/2 gal/min
LP GAS Supply Pressure inlet. min.
11” 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
UNPACKING THE AQUASTAR HEATER
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.