Local plumber recently replaced the heater tank in our Mira Azora shower.

Last week we noted it smelling and getting hot.

Plumber came back and claimed could see nothing wrong. Wife then used it and it stank and got hot again.

Plumber came back and switched it on with the cover off….even I could see the sparking and glowing off the blue wire at top of heater tank. He tightened up the wire, watched it and no more red glowing, etc.

Now if the shower was running for a long time, would it be normal for where the blue cable goes in to get quite warm?Basically I ran the shower for a fair time, switched off at isolator, etc then took cover off. Blue cable connector a tad warm to the touch.

Bit concerned…..

Give Mira a call in the morning

0844 571 5000

http://www.mirashowers.co.uk/contactus/landing.htm

In short – Don’t worry, it will get warm.
Sounds like the screw holding it down was maybe cross threaded or just not fully screwed down and so the wires had a loose connection causing the sparks and excessive heat. Now that it sounds like the plumber has sorted that issue you’ll be fine. Could be worth checking the wires are securely down? – edit re-read, sounds like the plonker hadn’t fully screwed down the blue wire when replacing the tank.

The wires do get hot in use due to all the current they carry (44 amps) but the silicon insulation on those wires is rated far beyond normal use.

Yeah, if the wire hadn’t been tightened up well enough you would have more resitance across the connection (possible arcing?), which would cause a lot of heat build up. We had the same thing, but in our isolator switch.

It will get warm even when the connection is good, as it is passing a lot of current. Ours is a 10.5kw shower, which is around 45 amps.

Just be sure to keep an eye on it and turn it off it you notice anything smelling bad or getting excessively hot like you have already done.

Loose connections like that in showers can cause problems if left for a while but sounds like you caught it quick.