We sell hundreds on Elecro Vulcan Nano heaters every year and we think we have been asked every possible question about them. They are so easy to install and very reliable but if yours does go wrong try these troubleshooting tips to get it working.

Will not start heating.

1. Check you have connected it the right way round. The unit has a flow switch to detect  if there is any water flowing through it and it will not start up unless there is. If you connect the pipes the wrong way round the water flow will not open the flow switch and it will not start.

2. Check you have sufficient water flow. This is a very common problem. As mentioned above, the heater has a flow switch to detect  if there is any water flowing through it and it will not start up unless there is. The heater requires a flow of 1,000 litres per hour to open the flow switch. If your pump is not powerful enough to deliver 1,000 litres per hour then the heater will not work. Your pump will need to have a stated capacity of at least 1,500 litres per hour.

A small pump may say in the specification that it has a capacity of 1,000 litres per hour but it will not deliver all of that capacity. Once the pump is connected in the system the capacity will be reduced by about 35%. In addition the paper filter cartridge could be clogged up. Try taking the filter out and run the pump without it for a short time. If the heater starts then that was the problem. Only do this to test the heater. Don’t leave the filter cartridge out permanently  – get a new one. If that does not work then the pump is not working at its stated capacity. You will need to replace the pump with a bigger one.

Another way to check if lack of flow is the problem is to manually open the flow switch. Turn off the pump. Unscrew the union that holds the flow switch in place and take the flow switch out. It looks like a little paddle. Gently push the paddle and watch the red light. It should come on. If it does let go of the paddle  – don’t have the heater on for too long without water flowing over the element. 

There is a leak

If your heater is leaking like the one in the video below then you should check the ‘O’ rings. There are two ‘O’ rings on each side of the heater. Follow the steps on the images underneath the video. 

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