Heatrae Sadia Electric boiler - no hot water

[Abzkhan87]

I have a Heatrae Sadia Megaflo electric boiler which is producing no hot water. I have recently moved to the flat (3 months) and the bolier is out of warranty. I am very reluctant to call out an engineer and fork out £ amounts of money as it could it be something very simple.

I am not sure what to check for and have read on several sites about the electrics tripping? But I haven't a clue how to check this. I have tried turning off the the mains switch and turning it back on but no luck.

Is there anything else I could check for before calling out for an engineer?

Advice is much appreciated.

 

[Mottie]

Follow the cable out from the boiler. Does it go to a switched box? Does it have its own fuse within the main fuse board?

 

[Abzkhan87]

The cable leads to a mains switch. About half a meter the switch is a squared shaped "board" that's written fuse on it.

Thanks for the reply.

 

[oldbuffer]

A picture of the Megaflo (which is an unvented hot water cylinder rather than a boiler) together with the wires connected to it and the switches / fuses at the other ends of those wires would be very useful.

I'm assuming you have no boiler, gas fired or otherwise.

You are likely (but not certain) to have two immersion heaters inside the cylinder. Each will be connected to a separate electrical outlet by means of a (normally) white electrical lead about 10mm in diameter. The lead from the lower immersion heater may well be fed with off-peak electricity, which is only available between (about) midnight and 5:00. This heats all the water in the cylinder, ready for the day's consumption. The upper immersion heater only heats about 1/3 of the cylinder and is useful if you run out of hot water during the day. Off peak electricity is around half the cost of ordinary electricity.

There are a number of possibilities. Each immersion heater has two thermostats. One switches the heater off when the water is hot and then switches back on when it cools. The other (the "overheat" thermostat) switches the heater off if the water gets too hot, and has to be manually reset - its a safety device. It could be that one or both overheat thermostats has tripped. Its also possible that the immersions are simply not switched on. Whatever the cause, without the right tools its not possible to diagnose the fault, and you will probably need to call an engineer. It needs to be an engineer with a "G3" qualification, without which no one is allowed to work on these cylinders. Incidentally, unvented cylinders are meant to be serviced annually.

See if you can get some suitable photographs on here - it just might be something very obvious.

 

[Abzkhan87]

Oldbuffer, your response is much appreciated. I will be uploading some photos shortly so maybe that could help.

It looks like it may have well to looked at by an engineer as it could be anything that you just mentioned.

Thanks.