Download  Print this page

Bosch AE12 Troubleshooting Manual

12 kw electric tankless water heater
Hide thumbs
   

Advertisement

Quick Links

Technical Service Bulletin
12 kW Electric Tankless Water Heater
Troubleshooting Guide
Models: AE12, RP12T, US12
DANGER: ELECTRIC SHOCK
ELECTRICITY IS EXTREMELY DANGEROUS.
TAKE EXTRA PRECAUTIONS AND
DISCONNECT THIS PRODUCT FROM THE
ELECTRICAL SUPPLY BEFORE CLEANING,
SERVICING OR REMOVING THE COVER.
BOSCH ELECTRICAL APPLIANCES
SHOULD ONLY BE SERVICED BY A TRAINED
TECHNICIAN OR LICENSED ELECTRICIAN.
Bosch technical support is available at 866-330-2729.
Please document results from each troubleshooting step
prior to calling. Without this information documented, we
cannot make a determination as to what is wrong with your
water heater. This will delay a resolution.
Introduction
Who should perform the troubleshooting?
Anyone who has the qualifications to work safely with 240VAC. If you
do not possess the tools or the knowledge to work safely with
240VAC, contact a licensed professional.
What does this troubleshooting guide cover?
This guide covers every test we can advise you to perform on the
location, installation, and water heater. With ALL the information
from ALL the tests in this guide, it is possible to diagnose any water
heater of this type to a point where we can advise a repair or cover
warranty.
Required tools:
Adjustable wrench
Empty gallon container
Digital multi-meter
Phillips head screwdriver
Flat head screwdriver
Step 1 – Document installation details
Record information in Step 1 of the Building and Install
questionnaire on page 5.
DANGER: ELECTRIC SHOCK
FOR STEPS 2, 3 AND 4, SHUT OFF THE
CIRCUIT BREAKER POWERING THE
APPLIANCE, LOCK IT, AND VERIFY THAT
THERE IS NO VOLTAGE AT THE UNIT.
Step 2 – Water supply and water heater settings
Verify the heater is installed in one of the two positions (inlet/
outlet connection on bottom) shown in Fig. 1.
Installation #1 (front view)
Installation #1 (front view)
Hot
Hot
Cold
Cold
Installation #2 (front view)
Installation #2 (front view)
Hot
Hot
Cold
Cold
Figure 1
Hot
Hot
Cold
Cold

Advertisement

Table of Contents
loading

  Related Manuals for Bosch AE12

  Summary of Contents for Bosch AE12

  • Page 1 TECHNICIAN OR LICENSED ELECTRICIAN. APPLIANCE, LOCK IT, AND VERIFY THAT THERE IS NO VOLTAGE AT THE UNIT. Bosch technical support is available at 866-330-2729. Please document results from each troubleshooting step Step 2 – Water supply and water heater settings prior to calling.
  • Page 2: Step 3 - Physical Inspection

    Troubleshooting Guide | AE12, RP12T, US12  Make sure the heater is not being supplied by preheated or Checking for plumbing crossovers:  recirculated water. Keep water supply off to the water heater using the contractor provided isolation valves, isolating the hot water Verify that the cold water supply is connected to the INLET ...
  • Page 3 Troubleshooting Guide | AE12, RP12T, US12 Checking the Thermal Cut Out:  Figure 4 Locate the thermal cut out switch (see Fig. 3). Figure 3 Reset button on Thermal Cut Out  Check the fl ow switch for continuity. With no water fl owing through the unit, check continuity between the brown wire and the yellow wire on the circuit board using 100 ohms scale (see Fig.
  • Page 4 Troubleshooting Guide | AE12, RP12T, US12 Check the resistance of the elements. Check to see if either element is grounded to the water tubing.   Ensure that the power to the unit is turned off. Ensure power supply to the unit is off.
  • Page 5 Troubleshooting Guide | AE12, RP12T, US12 Questionnaires Building and Installation: STEP 1: Bosch Customer # (if known) Owner’s Name? Owner’s address? Owner’s phone number? Model and serial number? Model: Serial Number: Where did you purchase this water heater? Name of installer and phone number?
  • Page 6 Troubleshooting Guide | AE12, RP12T, US12 Water Heater: STEP 3: Are there any burned or melted wires in the unit? Yes No Are there any signs of water leakage? Yes No Is the thermal cut out tripped? Yes No If the thermal cut out was tripped, have you reset it? Yes...

This manual is also suitable for:

Us12Rp12t