Customer FAQs

Here you'll find our most frequently asked questions specific to the end users of our appliances.

Access the most frequently asked questions and details about our products and services.

General Questions

Most plumbing and trade stores will be able to sell you a Bosch Hot Water system. To locate these suppliers, we suggest searching online, newspaper advertisements, or consulting the Yellow Pages. If you are still having difficulty, please telephone us on 1300 30 70 37 and we will assist you.

User manuals for installation and/or operation can be found in User Manuals and are available for download.

Each product has a warranty which covers any manufacturing faults. The specific warranty period for your Bosch water heater can be found in the appliance’s user manual. For more information, please visit Warranty & Servicing.

Bosch warranty covers manufacturing defects that may occur with the appliance. Issues caused by faulty plumbing or poor installation and commissioning are not covered by the manufacturer’s warranty. For full conditions refer to the warranty statement found in the installation instructions. Alternatively, download a copy of our warranty conditions found in Warranty & Servicing.

If you experience issues with your appliance inside of the Warranty period, please book a service online and we’ll get in touch with you shortly to arrange an appointment time.

A hot water heater should be installed as close as possible to the most frequently used hot water point. Other factors which may influence the installation position include the length and size of the gas supply pipe, the length of hot water pipe, position of existing doors and windows on the house. Australian Plumbing Standards include minimum clearances and distances which installers must meet.

Bosch has an extensive range of Continuous Flow water heaters which includes models suitable for internal and external installation. For more information, visit our Hot Water page and view our product brochures.

Your local licensed plumber/gasfitter will be able assess your hot water requirements and suggest the appropriate model for your application while taking into account the regulations governing installation of gas appliances.

Some parts of our range such as the Bosch 32 and OptiFlow all require 240 volts to operate. The Bosch HydroPower and Pilot models do not require 240 volt power. Learn more about the specifications of our hot water units on our product page .

Yes. Only suitably qualified plumber/gasfitters are permitted to install gas hot water heaters. The installing plumber/gasfitter is qualified to install and commission gas appliances, and is able to advise on the operations of the gas appliance upon completion of the installation. The installer is authorised to issue a Certificate of Compliance at the completion of the installation.

In most situations a Certificate of Compliance is required. The installer will be aware of any additional State-based plumbing regulations which affect the installation.

Our OptiFlow range of water heaters along with older Highflow water heaters with a ‘H’ in the part number are suitable for installations involving solar input. Highflow water heater models without ‘H’ in the part number are suitable but a solar transfer valve is required. Hydropower and pilot models are not suitable.

In most domestic water supplies in Australia, Bosch hot water units are suitable, however in areas with poor quality water, for example bore water, Bosch water heaters may not be suitable. All water heater installation and operating instructions now include the attached water quality statement.

An auto changeover system is preferable as this ensures you have continuous supply of LP gas. You must still regularly check to see the valve has automatically changed, and arrange for the empty cylinder(s) to be filled. Please discuss this with your LPG supplier.

Yes. In most cases, LP gas is supplied from cylinders located on the customer’s premises. When there is an interruption to the gas supply or no gas in cylinders, the water heater will make repeated attempts to light. If the water heater has not lit after a set number of attempts, the water heater will shut down as a safety precaution, and a reset will be required. Your LPG supplier will be able to discuss possible solutions for supply of LPG based on your circumstances/location and gas requirements.

Your plumber will be able to measure the gas load of all appliances and work out the appropriate gas supply necessary. LPG is best supplied in 45Kg cylinders, and multiple cylinders may be required.

The low temperature potential in you area will also be a factor the plumber will take into consideration because the liquid in the bottle has to vaporizes and low temperatures reduce the ability of the liquid to become a gas.

We also highly recommend that you do not use BBQ cylinders with your Hot Water System.

When purchasing your Gas bottle, we advise that you discuss with your LPG supplier to arrange for an auto change over system for your LP gas to ensure you have a continuous supply of gas. However you must still regulary check to see if the valve has automatically changed and arrange for the empty bottle(s) to be filled.

The temperature and flow rate fluctuations could be caused by a number of things - insufficient gas pressure, low or high water pressures, difference between cold and hot water pressures. The best way to deal with this situation is to have your Bosch Hot Water unit inspected by a suitably qualified plumber/gasfitter familiar with the Bosch water heaters. Bosch units should be commissioned on installation and regular services at intervals of every 2 years which should ensure such fluctuations do not occur.

Bosch recommends that your water heater should have a full service, safety, and performance check carried out at least every 2 years by a qualified plumber/gasfitter familiar with Bosch hot water heaters. Bosch can provide a checklist with recommended service criteria. Bosch can also recommend Bosch accredited service technicians.

To find your nearest service technician, click here

There is not really anything a consumer can check other to see if there may be a smell of gas around the water heater. You should ask a plumber to inspect all gas piping and connections on the household gas supply line to check for any gas leaks and seal them if found. Have the appliance serviced to ensure correct operation which will ensure maximum energy efficiency.

Bosch external water heaters are designed to be installed outside, and where there are ants, spiders, and other small creatures, they can enter the water heater through the air intake openings in the water heater. Since the air is necessary for complete combustion of the gas, these openings cannot be blocked off. We recommend performing regular inspections around the appliance, and if the vermin infestation continues, consult with a qualified pest exterminator about possible solutions based on local conditions. The use of flammable sprays around the water heater is only advisable after the appliance is turned off and disconnected from the power supply. If you do spray around the water heater, you should wait 30 minutes before turning on appliance.

Bosch has a comprehensive network of Authorised Service Agents around Australia, each of whom will be able to service your water heater. Please telephone the Customer Contact Centre on 1300 307 037 , and the operator will assist you with the contact details of a Service Agent near you.

Alternatively you can use our installer locator by clicking on the link below:

Installer Locator

Gas safety standards and state based regulations require that only qualified service technicians work on gas appliances. Servicing by a non qualified person is not permitted. Please telephone the Customer Contact Centre on 1300 307 037 , or use our service technician locator to assist you with the contact details of a service technician near you.

To find a service technician, click here

Bosch has a range of OptiFlow and Highflow accessories, including fully enclosed recess boxes (Highflow models only), semi–enclosed recess boxes, and pipe covers. Your installer will be able to assist you with recommendations.

General Questions for Products

Bosch offers temperature selector Pads as accessories which can be attached to the Bosch Highflow water heaters. These temperature selector pads give the consumer the ability to select the outlet water temperature of the water heater.

No, the hot water unit can only deliver one temperature at a time, even though you may have multiple temperature selector pads.

Standard Bosch Highflow water heaters are factory set to supply water at a temperature of 55°C. The temperature of the hot water delivered by these units can be increased to as high as 75°C, which means that a tempering valve may need to be installed in the house for safety.

Bosch also has available Highflow water heaters which are locked at a maximum delivery temperature of 50°C which means that a tempering valve is not required to be installed in the house. These locked water heaters cannot be unlocked to deliver higher temperature hot water.

Yes, retro fitting of temperature selector pads is possible with a minimum of difficulty.

The default hot water temperature from a unlocked Highflow water heater can be increased to either 60°C or 75°C by the installing plumber.

Bosch supplies Highflow water heaters locked to deliver a maximum temperature of 50°C. These water heaters can be installed in situations where 50°C is required (based on state based regulations). The installation of the tempering valve is not required as the water heater conforms to the Australian Plumbing Standard. The water heater will only supply a maximum of 50°c to all the plumbing fixtures connected to the water heater.

The plumbing regulations allow only minor adjustments to the outlet temperature of a locked 50°C Highflow heater. The outlet temperature at the nearest sanitary fixture must not exceed 50°C after the minor temperature asjustment. This adjustment must be performed by a licensed plumber using a temperature selector pad to make the adjustments.

Yes. The installing plumber can adjust the outlet temperature by inserting pre-set temperature bridges, or by adjusting settings using a temperature selector pad. Special consideration should be given to the need to increase temperature based on the application and hot water requirements to prevent scalding.

Yes. A 240 volt 10 amp external power outlet is required to operate the Highflow range of water heaters.

Yes. The power should remain on at all times.In cold climate areas the power also provides frost protection for the appliance. If the water heater will not be used for extended periods, it is recommended that the system be drained of water.

Bosch Highflow water heaters are suitable with most tap ware but some fixtures are designed to restrict the flow of water. Bosch Highflow water heaters have a minimum flow rate to activate and when mixing hot and cold, the flow rate through the hot water system may be too low to keep the burner alight. The use of a controller would assist in this circumstance as the customer can request the temperature and only turn on the hot water tap. Alternatively the plumbing fixture can be inserted by the plumber.

The Bosch Highflow water heater cannot compensate for the poor or faulty plumbing or blockages in water lines. A plumbing inspection should take place and old or faulty tapwear replaced. Most tapwear have inbuilt filters or strainers to aerate and create smooth flow of water. These should be inspected and cleaned as they could be restricting the flow of water.

There are two (2) things you can check.

You can check the electricity supply to the Highflow:

• Make sure all the hot water taps are off, then turn off the power point where the appliance power is connected, and remove the power lead from the socket. Wait for at least one (1) minute before plugging into the power point again and switching on the power. Wait for at least one (1) more minute while the Highflow carries out it’s own diagnostic check, then turn on a hot water tap and test for hot water.

You can also verify that the gas supply is available:

• Check other gas appliances to see if they are operating correctly (gas cook top, gas heating appliance). For customers using natural gas please check the gas meter assembly ensuring that the main valve is open. Contact your local gas authority if no gas is available or the gas valve is turned off as there may be a reason. For customers using LPG, check that the gas cylinders are heavy or full. Ensure that the supply valve is op

When a hot tap is opened, the Highflow water heater will ignite within a second or two and begin heating the water. The additional time taken for the hot water to get to the hot tap depends on the length and size of the household’s hot water pipe between the water heater and the hot tap.

Please telephone the Customer Contact Centre on 1300 307 037 , and the operator will assist you with the contact details of a Service Agent near you. Bosch has a comprehensive network of Authorised Service Agents around Australia, each of whom will be able to service your water heater. Bosch recommends a safety and service inspection at least every 2 years,and a recommended service checklist is available from Bosch which should be completed by the attending service technician.

Periodically inspect the water heater location to make sure there is no flammable materials or rubbish leaning on or near the appliance, and that the surrounding area offers safe access by a service technician if required. The consumer should also check that the water heater is securely fixed to the wall, the flue is free of any obstructions,that there are no heat marks or black sooting present on the wall on which the appliance is mounted.

Cover off inspection:

  • Ensure no vermin; e.g. spiders, ants etc, are living in the appliance.
  • Operate water heater and ensure that flame is blue (not yellow), check general condition of the appliance and wiring.

Hydropower water heaters use the low voltage electricity generated by the movement of water through the hydrogenerator within the water heater when you open a hot water tap. The low voltage electricity generated by the hydrogenerator provides the power required to ignite the appliance.

No external power is needed. The low voltage electricity generated by the hydrogenerator provides the power required to ignite the appliance

The external Hydropower models can be installed in locations where the occasional frost occurs, but an Exogel valve is required to be installed to provide adequate frost protection. For locations where frequent frost occurs, an internal Hydropower model or internal OptiFlow would be more suitable, or one of the external Highflow models with builtin frost protection circuit may be more appropriate.

Water Flow: The water flow can be adjusted by rotating the water flow selector knob clockwise for decreased water flow, or anticlockwise for increased water flow. Increased water flow will give lower water temperature, and decreased water flow will give higher water temperature.

Gas Rate: The amount of gas going to the burner can be adjusted by moving the slide from left to right. Sliding to the right will increase the gas burner rate while moving to the left will decrease the gas rate. The gas rate will affect the temperature of hot water delivered by the water heater, and is appropriate in area where the incoming cold water temperature is high in summer.

The front cover can be removed by loosening the thumb screws (thumb screws are not required to be completely removed). Hold the side of the cabinet and pull forward and slightly down which will disengage the front cover . Once free, hold and support cover and safely remove to a suitable location. To reinstall, locate the top of the cover near the top supporting bracket and slide into position, push back, and locate cut outs on thumb screws. (Require pictures of cover removal)

Yes. The Hydro models require a minimum flow rate of 3.5 litres per minute to operate the hydrogenerator, and to activate the mechanical controls. The minimum flow rate will depend somewhat on the position of the water flow selector knob of the appliance, and the water pressure to the water heater.

The Bosch Hydropower water heater uses no power and no gas when idle and therefore you only pay for the water and energy used at the time of heating. To operate the water heater correctly, turn on the hot water tap at a reasonable rate and wait for hot water to come through. Once hot water has arrived, open the cold water tap and mix to achieve the desired temperature. Please note that not all tap wear is suitable for the Hydro Power unit.

No, controllers cannot be attached to Hydropower model.

The Hydropower water heater temperature cannot be preset like the Highflow products, however, the performance can be adjusted to supply more or less water flow and to increase or decrease the temperature of the unit.

Yes. Tempering valves can be used with Hydropower models. High performance tempering valves are always suggested to provide complete and safe mixing.

When a hot tap is opened, the water heater will ignite within a second or two and begin heating the water. The additional time taken for the hot water to get to the hot tap depends on the length and size of the household’s hot water pipe between the water heater and the hot tap.

The Hydropower product has a safety time to allow ignition and safe operation. If this short period expires without ignition then a re-ignition attempt will be required. The hot water tap should be turned off, and then on again.

If the heater still fails to ignite, please call the Bosch Contact Centre on 1300 30 70 37 who will be able to recommend a suitably qualified service technician who will be able to attend your water heater.

If this fails to work then you can test the appliance with the assistance of a second person. Ask someone to activate a tap while the other stands near the water heater. Once the tap is turned on the person at the water heater needs to observe the water heater. The correct operation of the water heater can be observed by: (a) listening for the spark ignition, (b) observing the main burner flame through the cover.

Please telephone the Customer Contact Centre on 1300 307 037 , and the operator will assist you with the contact details of a Service Agent near you. Bosch has a comprehensive network of Authorised Service Agents around Australia, each of whom will be able to service your water heater. Bosch recommends a safety and service inspection at least every 2 years,and a recommended service checklist is available from Bosch which should be completed by the attending service technician.

Periodically inspect the water heater location to make sure there is no flammable materials or rubbish leaning on or near the appliance, and that the surrounding area offers safe access by a service technician if required. The consumer should also check that the water heater is securely fixed to the wall, the flue is free of any obstructions,that there are no heat marks or black sooting present on the wall on which the appliance is mounted.

Cover off inspection:

  • Ensure no vermin; e.g. spiders, ants etc. are living in the appliance.
  • Operate water heater and ensure that flame is blue (not yellow), check general condition of the appliance and wiring.
  • Please note: Plumbers and gasfitters are trained and experienced in the servicing and safety inspections of the gas appliances. Servicing must be carried out only by these qualified people.

Bosch external water heaters are designed to be installed outside, and where there are ants, spiders, and other small creatures, they can enter the water heater through the air intake openings in the water heater. Since the air is necessary for complete combustion of the gas, these openings cannot be blocked off. We recommend performing regular inspections around the appliance, and if the vermin infestation continues, consult with a qualified pest exterminator about possible solutions based on local conditions. The use of flammable sprays around the water heater is only advisable after the appliance is turned off and disconnected from the power supply. If you do spray around the water heater, you should wait 30 minutes before turning on appliance.

Check operation of water heater.

Temperature controller on display.

The majority of Bosch water appliances are designed to be installed externally and all gas appliances require ventilation opening to assist in complete combustion. Where there are vermin including ants, spiders and other small creatures, it is advisable to perform regular inspections on the appliance. Customers should consult with a qualified pest inspector about possible solutions based on local conditions. The use of flammable sprays is only advisable after the appliance is turned off and disconnected from the power supply. Please wait ½ hour before turning on appliances.