Bosch Hot Water Fault or Error Code E4

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Bosch Hot Water Heater Fault or Error Code E4 Troubleshooting Guide

Bosch is one of Australia’s favourite manufacturers for hot water heaters and with over 127 years of know-how it’s easy to see why. The Bosch hot water heater range is durable, reliable and backed by extremely generous warranties.

Bosch hot water system

Giving you peace of mind knowing that you have purchased a quality appliance. Like with any appliance, faults can still occur within the Bosch hot water heaters.

Thankfully, if you chose to have the optional hot water temperature controller installed with your Bosch gas hot water heater then a fault code will display in the event of any problems within the unit.

This is a handy feature as it allows you to organise a prompt repair before the issue turns into a major problem.

One of the error codes that may display on the digital monitor of your temperature controller is a Bosch fault code E4.

What does the Bosch error code E4 mean?

If a fault code E4 is flashing on your temperature controller monitor you are advised to turn off the appliance immediately.

The Bosch error code E4 signifies that the air temperature sensor within the unit has detected overheating which may be caused by leaking combustion products within the combustion chamber.

For safety reasons, if this code is showing turn of the hot water unit at the power point, remove the plug from the electrical socket and call a fully qualified technician as soon as possible.

Urgent resolve of the Bosch fault code E4 is required

The Bosch error code display E4 requires immediate investigation. This is a serious issue within the hot water system and, for safety reasons, the appliance will close the burner and shut itself off.

You should never attempt to restart your hot water system until the Bosch fault code E4 has been resolved.

For a fast and reliable repair of the Bosch fault code E4 call Jim’s Plumbing.

We have a local plumber available near you 24 hours a day, 7 days a week, including all public holidays.

In a plumbing emergency we can have a fully qualified plumber pulling into your driveway within only an hour* of your booking.

For non-emergency gas or plumbing situations we still provide a same day plumbing service.

If you need a plumber in Adelaide, Perth, Melbourne, Brisbane, Sydney or Canberra call Jim’s Plumbing on 1300 133 509 – 24/7.

Your attending plumber from Jim’s will thoroughly inspect your hot water heater to find and rectify the exact cause of the Bosch E4 error code display.

The combustion air and backflow vent piping will also be checked for any blockages and all venting specifications will be inspected to ensure correct specifications are met.

For a plumber in an emergency you can rely on Jim’s Plumbing for a fast, reliable and affordable repair, with customer satisfaction and quality workmanship guaranteed – first time, every time.

No Interest Ever!* Payment Plan Options Available

No Interest Ever!* payment plan options available on hot water heater replacements to help ease any financial stress this burden may cause. If your bosch hot water heater is leaking, or you have no hot water, we can often have a plumber to you within the hour*.

Choosing the Correct Hot Water System

Choosing the correct hot water system can be difficult, as there are so many options to choose from; Click on the links to find out more about these systems.




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Please be advised that we may have additional Bosch Hot Water System models available.

Simply book a plumber online now, or phone 1300 133 509 to book now.

*NO INTEREST EVER!* PAYMENT PLAN, “Fees, terms and conditions apply”.

No Interest Ever!* Payment Plan offered through Certegy Ezi-Pay Express. No Interest Ever on your hot water heater replacement or new supply and installation, gas service, water service or drain replacement. Conditions apply.

Information on this page is subject to change. Commercial hot water systems also available on enquiry.

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