Bosch Appliances 125HX NG specifications No Spark AT the Pilot

Problems are stated in upper case, bold face. Most common causes for the problems follow in order of likelihood. The suggested solutions require that the cover be taken off. To do this, remove incandescent particle tray, pull off the temperature adjustment knob and unscrew and remove the plastic collar. Pull main cover out toward you and lift up and out.

NO SPARK AT THE PILOT

1. On/Off switch is not ”On” (Position ).

The On/Off switch is located behind the flipdown cover plate on the front panel strip. See fig. 9.

2. Cross over in water lines

To confirm there is no cross-over in the plumbing, shut off the cold water supply to the AquaStar and open all hot water faucets. There should not be any water flowing at any faucets. Water running is a sign of a plumbing cross- over. Consult your plumber.

3.Water flow is not sufficient to activate heater. Water flow rate at faucet is below minimum flow needed to activate heater. When temperature adjustment knob is turned all the way clockwise, the AquaStar model 125HX requires 1/2 gallon per minute flow to activate the heater. As a reference, this is a flow which would fill a quart jar in

30seconds. If the temperature adjustment knob is turned fully counterclockwise, a flow rate of 1.1 gallons/minute is required to activate the heater.

The red LED light (located behind the coverplate on the front panel) flashes when the water flow is not enough.

4.Water inlet filter is clogged

Water flow is restricted, preventing needed flow to activate heater. Clean water inlet filter screen.

5.Cold incoming water connection made to wrong side of heater

Make sure cold water inlet connection is on the right side of heater when you are facing heater.

6.Water valve parts may be dirty or components damaged

First check that venturi is free of dirt particles. Water valve and component parts must be totally free of dirt. In hard water areas, mineral deposits can eventually (3-5 years in hard water areas) corrode the water valve parts to a point where they will need replacing. Any sign of moisture or corrosion at the joint of the water valve and the gas valve is a sign that the water valve components need to be serviced immediately.

7.Poor circuit connections at the ECO (overheat sensor) or the flue gas safety device

Ignition sparker will not operate if the electrical circuit is interrupted. Check that the connections to the ECO and Flue Gas Safety Device are secure and tighten if necessary. If the Aquastar is Powervented, check spill switch reset

SPARK APPEARS AT PILOT WHEN HOT WATER TAP TURNED ON, BUT PILOT AND BURNERS WILL NOT IGNITE

1. Air in the Gas Line

Normally this is a problem at time of initial installation, after the pipes have been worked on, or after a gas supply line has been allowed to empty. Bleed the air trapped in the gas line by turning the hot water faucet on and off until the air has been cleared from the line.

2. No gas to the AquaStar

A. Gas cock on gas line may not be open

B. Gas regulator may be shut or damaged. Replace or unlock the regulator. Note: The regulator furnished with the heater is exclusively designed for low gas pressure. Excessive pressure will lock it up. Locking usually happens when using propane gas if the gas pressure between the gas tank and the water heater’s gas regulator has not been reduced. See Page 2 for recommended correct gas pressure. To unlock a regulator, consult your gas supplier or call CEC.

3. Pilot orifice or gas valve is dirty

Clogging of the pilot burner can be caused by dust in the air or dirt in the gas. The pilot orifice or gas filter may need to be cleaned or replaced.

4.Pilot electrovalve switch may need to be replaced (See Fig 13).

Call CEC.

5.Electronic Control Box may need to be replaced (See Fig 13).

Call CEC.

12 6 720 606 804 (02.10)