It’s been quite an interesting week in Adelaide for me as we head into winter, the phone has been ringing steadily with people inquiring about Hot Water Repairs and Installations Adelaide.  Being the Hot Water Wizards we are always busy with Bosch Hot Water Services whether it be a new install or a repair on an existing Bosch Hot Water Service through warranty or just a service call, we do it all when it comes to Hot Water in Adelaide.

BOSCH 18e Hot Water Service

In this week’s post I’m going to talk about the BOSCH 18e Natural Gas External Hot Water Service. I often get phone calls from my customers who have a BOSCH 18e Hot Water System and they tell me that the unit has stopped working or is leaking water, this is due to the fact that these units are all now at least 10 years old and coming to the end of their working lives.

 In most cases these are now being upgraded to a newer model called the BOSCH 17e, but that is not always the case as I’m going to explain this week.

A customer in Norwood, Adelaide, South Australia recently contacted with me because we are the “Hot Water Wizards of Adelaide” and wanted some advice on repairing his Bosch 18e, the unit was displaying an error code 14 on his temperature control pad inside the home, which indicates a faulty internal wrap around fuse, this device detects over temperature and causes the Hot Water unit to shut down to protect itself from catastrophic failure.  

Hot Water System Fuse

This fuse is located at high level inside the Hot Water Service casing and wraps around the copper heat ex changer.  It is approx 3mm in diameter and approximately 1m in length and gets wrapped around the heat ex changer 2 times, it is held in place by a series of stainless steel clips and is then plugged into its relevant terminal connections to communicate with the PCB.

When it comes to replacing a part such as this on a Hot Water Service of this age the most cost effective method of resolving this problem is to supply and install a new hot water service.  The reasoning behind this is due to the labour which is involved with actually being able to remove the old fuse and then install a new one.  In order to get to the fuse nearly every component of the BOSCH 18e needs to be carefully removed and if you have ever looked inside one of these units it’s a mine field to say the least.  My customer in this instance insisted on ordering the new part and repairing the existing Hot Water Service, so I did.  


new fuse for bosch hot water system


BOSCH 18e copper heat ex changer before the wrap around fuse is installed.

Once the part arrived from BOSCH I made a time to attend my customer’s house and start the repairs.  The first components to come out of the unit are related to the gas burner and fan and are relatively easy to remove, it wasn’t until I started on the sections of the Hot Water unit which relate to water section that trouble started appearing, corrosion had set in and it started making the removal of further components near on impossible, after much persistence I had to pull up stumps and tell the customer the bad news.

Unfortunately after much perseverance and patience the old BOSCH 18e could not be salvaged, my customer was very understanding and agreed that the only way forward was to get a new BOSCH 17e.  As I previously mentioned there was a control pad already installed onsite, this is no longer compatible with the new units and therefore also needs replacing if the customer wants to have a control pad in the future, the wiring is compatible just not the control pad.  Swapping over the old control pad with the new is probably the easiest part of the project as the fixing holes line up and the wiring is very simple for a licensed plumber/gasfitter Adelaide.

When it comes to installing the pipe work the configuration (when your standing in front of the unit looking at it) as far as hot on far left and gas on far right with cold in the middle is still the same, but the distances off the back mounting wall have slightly differed, so some adjustments will be needed when it comes to pipe work installation.  The mounting holes are now also at slightly wider (centres) so new fixing holes will also be required, all pretty standard stuff when we talk about installing a new Hot Water Service Adelaide.

Once all the pipe work and control pad has been installed and tested including working pressures of the gas on the BOSCH 17e its time to enjoy your HOT WATER!  With the new control pad installed my customer can now dial up the desired temperature of their shower or kitchen sink to do the dishes AND as a huge bonus the control pad can also be programmed to completely fill a bath to the desired height with warm water, amazing technology!

Finishing off this chilly week in #Adelaide if you do find yourself in need of some kind of Hot Water Repair please remember our licensed gas plumbers from Mayfair Plumbing and Gasfitting and visit us on the web at: or call Aaron on 0429 361 819 and discuss your next Hot Water project whether it be gas, electric, heat pump, lpg or solar we can help you.

This article was first published here:

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