WATER IS TOO HOT
1. Temperature Selection too high
Turn the temperature adjustment knob counter-clockwise (to the left) to lower the maximum water temperature. Note: This will increase the activation flow rate.
2.Inlet water temperature is very warm (60°-75°F) Reduce inlet gas supply to lower the heaters degree rise. Note: Only the Model 125BS should be used if the inlet water is preheated.
NOTE: Only the model 125B LPS or 125B NGS should be used if the inlet water is preheated.
3.Inlet filter screen is clogged, restricting flow Remove screen and clean it.
WATER IS NOT HOT ENOUGH
1. Temperature selection is set too low.
Change the setting. Turn the temperature selector knob clockwise (to the right). Note: this will decrease the activation flow rate.
2. Gas pressure is insufficient
It is extremely important for a tankless instantaneous water heater to have the right size gas line to obtain the correct gas pressure. See specifications on page 2. Unlike storage tank water heaters, the burners of a tankless water heater must be very powerful to heat water instantaneously since they do this only at the time hot water is actually being used. It is therefore imperative that the gas pressure requirement be met exactly. Insufficient gas pressure will directly affect the water temperature at the time of usage. See page 2 for correct gas pressure settings and see page 11 for proper gas line sizing.
3. Gas supply is insufficient
Make sure your main gas line is fully opened. If using LP gas, be sure that the size of the propane tank is adequate to supply the required gas pressure. See gas pipe sizing chart on page 11.
4.Cold water is mixing with the hot water between the 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 “NO SPARK AT THE PILOT” paragraph 4). Where automatic “anti-scald” valves are required by code, lower the temperature setting on the AquaStar as much as possible and balance the pressure between cold and hot water after the AquaStar.
5.Parts in water valve are dirty or damaged, which will prevent the gas valve from being fully opened.
If the internal water valve parts are damaged from water quality or use, or there is evident corrosion where the water valve and gas valve connect, then immediate service is needed. See step 9 under the problem NO SPARK AT THE PILOT. White vinegar should be applied first to any corrosion before the loosening of screws.
HOT WATER TEMPERATURE FLUCTUATES / UNIT DEACTIVATED
1. Unbalanced pressure in waterlines
The added restriction caused by the Aquastar in the hot water system can result in uneven pressures between the cold and the hot. In such cases when mixing cold water at the tap, the lower hot water pressure may be overpowered by a much higher cold water pressure, which may cause the Aquastar burners to shut down (deactivate). Make sure faucet aerators or shower heads are free of minerals.
Do not add any flow restrictor to the shower head. Typically this deactivation symptom is a result of the hot water being too hot to use comfortably. Warm inlet water generally causes this. Lowering the control knob setting and/or reducing the inlet gas supply to the heater should correct this deactivation symptom.
2. Temperature balance valves
If the inlet water temperature to the water heater is very warm the heater can produce temperatures that may be found to be too hot. A temperature balance shower valve can automatically mix in cold water to reduce such hot water temperature, in the event of any temperature instability with the use of a temperature balance shower valve, refer to shower valve manufactures instructions for internal adjustment setting. Adjustments should be made to the hottest setting in the shower valve. Additionally the temperature control of the heater can be adjusted to produce a more comfortable hot water temperature.
See SETTING THE WATER TEMPERATURE section.
3.Cold water is mixing with the hot water between the AquaStar and the outlet
See #4 under “NO SPARK AT THE PILOT”.
4.Inlet water pressure is erratic due to inadequate supply water pressure or saturated pressure tank on well system
Check the inlet water pressure. For installation on a private well system with the use of a pressure tank, the lowest pressure range setting recommended is 30-50 psi (2.07- 3.45 bar). Confirm that the pressure tank is not water logged.
5.Gas pressure is too low
See page 2 for correct specifications.
EXHAUST FAN DOES NOT OPERATE
1.Check the fuse (see fig 9)
2.Check all electrical connections
3.Check adjustment of microswitch (see Fig. 14)
FAN CIRCULATES WHEN HOT WATER IS SHUT OFF
1. Check adjustment of microswitch (see Fig. 14)
FAN OPERATES WITHOUT WATER FLOW
1.Unplug the heater and first check that all electrical and electronic connections in the heater are clean and tight.
2.Check adjustment of microswitch (see Fig. 14).
3.Control box may need to be replaced (see Fig 9). Check wire connections and test operation of control box (see Fig 9).
