Bosch Dishwasher SHI4302 Repair Manual

Bosch Dishwasher SHI4302 Repair Manual

This Repair Manual is designed to assist you in the evaluation, diagnosis and repair of the current SHI, SHU and SHV model dishwasher series. To better understand these appliances, their operation and construction we suggest that you read this manual thoroughly before attempting any repairs.

Technical Specifications

Electrical Requirements

Rating	120V / 60Hz
Dedicated Circuit	15 Amp
Total Amps (load rated)	11 Amp

Water Supply

Suggested Incoming Temp.	140° f
PSI Min / Max	20 / 60
Water Connection	3/8” Copper or Flexible Stainless Steel

Component Values

Component	Ohms*	Amperage	Other
Water Valve	1K	—	—
Drain Motor	16	.75	—
Circulation Motor	10	1.25	—
NTC	55K at room temp. (75° f)	—	Resistance decreases as temperature increases
PTC (actuator)	200	—	—
Heater	10.5	9.75	1200 watts

*always disconnect both component leads before measuring for resistance.

Electrical Warning:

To avoid personal injury and/or property damage it is important that safe servicing practices and procedures are observed at all times. Disconnect the electrical service before attempting any repairs, and live tests are to be performed by experienced and qualified service personnel only.

Bosch Dishwasher SHI4302 Product Overview

The Bosch dishwasher utilizes a two motor system with separate Circulation and Drain Motors, and a Flow Through Heater controlled by a Flow Switch and NTC Thermistor. With some models also having the advanced logic feature of an Aqua Sensor turbidity measuring devise, Fig. 2-1.

• A two motor system allows each motor to be designed for a single function, thus reducing overall size and energy consumption. While also reducing operating noise.
• The Flow-Through Heater allows a shorter heating cycle since all water must pass through the Heater, increasing water temperature by approximately two degrees a minute. To protect the heater from dry fire, the Flow Switch will not allow the Heater to activate unless water is flowing.
• Water temperature is controlled by the NTC (negative temperature coefficient). As water temperature increases the NTC records the decrease in resistance. The Control Unit Logic Board measures this resistance change and allows the program to advance once the correct temperature (resistance level) is reached.
• The Aqua Sensor turbidity measuring device, which is available only on select models, evaluates the pre-wash water using a beam of light and a pick-up sensor. If the beam passes easily through the pre-wash water then no additional wash water is added. If the beam cannot pass through, then the pre-wash water is drained and a fresh fill is added for the main wash cycle.

The heated water then advances through the system via a four level wash system that uses both an upper and lower spray arm as well as an overhead sprayer, Fig. 2-2.

Fig 2.1

Fig 2.2

Bosch Dishwasher SHI4302 Operation

The SHI or SHU 43** series operates using an electronic Control Unit. TO OPERATE:

• First depress the On/Off Button until it locks in place.
• Once the On/Off Button is depressed the LED above the previously used cycle will illuminate.
• To change the cycle, simply press the desired Cycle Button twice. The LED above that cycle will then illuminate.

As the program advances the Cycle Progress LED’s will illuminate (wash, rinse / dry). When the cycle is complete the Clean LED will be illuminated.

TO CANCEL A CYCLE:

Press the Power Scrub Plus and Regular Wash Buttons both in at the same time. The unit will then drain and the Clean LED will illuminate.

Please note: If the door is opened during the cycle, the On/Off Button will be reset to off andmust be depressed again to re-active the cycle. The cycle will resume from where it left off.

Bosch Dishwasher SHI4302 Cycle Chart

Rack System

Bosch Dishwasher SHI4302 Rack configurations for individual dishwasher models will vary. However, all Racks are constructed from a steel wire grid with a gray nylon outer covering.

Note: Racks may discolor due to the water supply or types of food remaining on the dishes. We recommend that a vinegar wash be used to assist in removing these stains. Start the unit, and let run approximately ten minutes, then pour in two cups of white vinegar and let the unit complete the cycle, repeat if necessary.

On select models the Upper Rack is height adjustable. To adjust rack height, or to remove the Rack from the unit. Fully extend the Rack as shown in Fig. 4-2

Note how the Rack Rollers are designed to ride on the outside of the Rails for a smoother operation. With the Rack fully extended. Lift up on the Rack until the Front Rollers disengage from the Rail. Now bring the Rack out further and allow the Rear Wheels to disengage.

Rollers:    Rack Rollers are a press fit making for easy removal and replacement.

Detergent / Rinse-Agent Dispenser

Located on the Inner Door is the Detergent / Rinse Agent Dispenser, Fig. 6-1. The Dispenser Housing is one assembly containing three individual components. Rinse Agent Dispenser. Detergent Cup. Steam Vent.
Note: Mechanical operation and removal of the Dispenser is shown in Section 4.

To fill or adjust the Rinse Agent Dispenser, open the Rinse Agent Door by pulling up on the Door Latch.
The Dosage Meter, item 1, is now visible. The Dosage Meter allows you to adjust the amount of Rinse Agent dispensed into the rinse stage of the cycle. The factory setting is three.
There is also an eyepiece, item 2, that provides a visual indication as to the amount of Rinse Agent remaining in the Dispenser.

To the right of the Rinse Agent Dispenser is the Detergent Cup, item 1.
Once detergent has been loaded into the cup, slide the Detergent Door, item 2, closed.
When the door is fully closed press down on the door end to lock it.

A white Locking Lever, item 1, will then extend. Once closed, the detergent door may be released by pressing in on the Locking Lever.
With the Detergent Door closed the Steam Vent is now visible, item 2.
During the drying stage of the cycle, steam is drawn through the vent and collects in a Condensation Tube.

Washability / Drying

WASHABILITY

There are four factors that play a critical role in Washability: Time, Temperature, Water and Detergent. It is important when attempting to determine the cause of a Washability complaint that all four factors be considered and tested.

• Time: The duration of the program is accurate (see cycle chart).
• Temperature: The wash and rinse temperatures are within the desired range (see cycle chart). Water: The unit is filling with the correct amount of water (Section 3, Fig.5-7) Detergent:  The detergent is fresh, and not being used in excessive amounts.
• Please note: Other factors such as clean filters, a properly routed drain hose, water hardness and quality, as well as loading of items will also effect Washability.

DRYING

As part of an energy saving design Bosch Dishwashers do not activate the Heating Element during the Drying cycle. Instead, the dishwasher utilizes a rinse temperature of up to 161° Fahrenheit, and the addition of Rinse Agent to achieve a quality drying result.

HOW THIS SYSTEM FUNCTIONS:

• During the rinse cycle water is heated to 161° Fahrenheit, this heat is transferred to the items in the dishwasher where it is absorb and stored.
• During the drying portion of the cycle all dishwasher items will then radiate the stored heat, thus evaporating any water that has collected on the items surface, burning it off and converting the liquid into steam.
• This process of “flash drying” is assisted by the release of Rinse Agent into the rinse water. Rinse Agent is a water softener that inhibits water from collecting or pooling, allowing it to be easily evaporated.
• The remaining steam is vented from the interior through the Steam Vent (Fig. 6-4, item 2) where it is then collected by, and drained from the Condensation Tube (Section 4, Fig. 7-5, item 2).

Service note: When confronted with a drying complaint, make sure the Rinse Agent Dispenser is full, and the rinse water temperature is within the desired range. Please remember that the unit will not dry without Rinse Agent.

Readmore and Download Bosch Dishwasher SHI4302 Repair Manual

Title	: Bosch Dishwasher SHI4302 Repair Manual
Format	: PDF
Pages	: 87 Pages
Language	: English
File Size	: 3 MB