Shower overheating no loose connection

[Ampo]

Hi all. Shower has melted on top left corner. I thought it would likely be a loose connections on the feed. On taking the cover off the 10mm coming in and connector block looks fine and is tight and I soon realised the burn Mark is from the live going from the block up to the top of the heating/pump canister. Connections are all tight. I have run it for 30 seconds and the live gets to hot to touch but the incoming 10mm is still cold so can only guess that it's an issue inside the heating unit that is then passing the heat down the live. Anyone ever come across this? I was just expending a simple loose neutral. Triton say there have been no recalls and were pretty uninterested. Sounds like a new unit needed but has left me curious if anyone has seen this before?

 

[Gavin John Hyde]

Can you upload pictures to help better understand what you are saying?

 

[markythesparky]

Change the shower.

 

[Ampo]

I'm not back home at the moment but can take a photo when I am. All you will see is the live cable going from the connector block up to a crimp on top of the heater unit (tritons live cable). The insulation has not perished but it's getting hot enough to burn through the plastic enclosure. Very strange.

 

[123]

Is the shower still under warranty?

Just because there has been no recall doesn't mean the shower won't be faulty, any make of shower can develop a fault. If it's under warranty don't remove it, check with Triton what to do. I know with Mira and Redring if the unit is faulty under warranty they come and sort it...you taking it back to supplier messes up your warranty

 

[Ampo]

No five years old. It's all good I'll just swap it out. Just thought it was quite a worrying scenario. If unnoticed for another couple mins could have easily melted through a hole and exposed live parts. When I get a min I'll chuck a clamp meter on it out of interest

 

[chris gray]

The element sounds like it’s had its day

 

[Deuce]

Definitely swap out the shower. Even if it was sat in front of me and I had time to work out what the fault was, whatever it was the answer would still be to buy a new one

A decent replacement is about £100, or less at trade... And my preference, for less still you can just come off the tap feeds and have a proper shower? I can't stand the electric ones!!

Just one thing to consider though, just in case it isn't the shower... Check the voltage on the supply circuit. If for whatever reason it is low then your shower will be drawing higher amps to compensate for the lower than rated voltage. I'm only saying this on the off chance that there is an obscure voltage issue which itself would need looking into. For the sake of passing a multi meter over the supply terminals you will know for sure.

 

[123]

Definitely swap out the shower. Even if it was sat in front of me and I had time to work out what the fault was, whatever it was the answer would still be to buy a new one

A decent replacement is about £100, or less at trade... And my preference, for less still you can just come off the tap feeds and have a proper shower? I can't stand the electric ones!!

Just one thing to consider though, just in case it isn't the shower... Check the voltage on the supply circuit. If for whatever reason it is low then your shower will be drawing higher amps to compensate for the lower than rated voltage. I'm only saying this on the off chance that there is an obscure voltage issue which itself would need looking into. For the sake of passing a multi meter over the supply terminals you will know for sure.

No it won't. The shower is a fixed resistance load. If the voltage goes down, so do the amps.

 

[Ampo]

Yeah I'll swap it was more just curiosity. Would ent use it now anyway. I'll take a look at supply voltage. Only been here for 3 months and been meaning to do a full test but haven't got around to it. This might prompt me now. I only need the next one to last a year and then I'm having a new bathroom with shower off the combi as it's also my preference.

 

[Deuce]

No it won't. The shower is a fixed resistance load. If the voltage goes down, so do the amps.

But wouldn't the fixed resistance draw higher amps as the voltage is reduced - the same level of resistance at lower voltage would demand higher amperage to meet the resistance surely?

As ever, I accept I might be wrong - ready to learn...

 

[Ampo]

I'm confused by this too. I would have calculated it as going up in amps

 

[Deuce]

I'm confused by this too. I would have calculated it as going up in amps

Exactly. Fixed resistance doesn't equal fixed current draw. With lower voltage it has the potential to carry more amps was my way of thinking

 

[123]

But wouldn't the fixed resistance draw higher amps as the voltage is reduced - the same level of resistance at lower voltage would demand higher amperage to meet the resistance surely?

As ever, I accept I might be wrong - ready to learn...

No! It's a fixed resistance load, the elements resistance will not change. So if the voltage drops then the current will drop, and vice versa.

Ohms law, R (the element resistance) is the one that will not change. I = V/R

 

[Jim_e_Jib]

Exactly. Fixed resistance doesn't equal fixed current draw. With lower voltage it has the potential to carry more amps was my way of thinking

It's Ohm's law - I = V/R

R is fixed so as V gets lower, so must I.

You can think of it as the voltage pushing the current through the resistance. A lower voltage means it pushes less current through.

If you run some examples with say a resistance of 10ohms and voltages of 240 and 220, you'll see the current drop.

Edit: beaten to it!

 

[Deuce]

No! It's a fixed resistance load, the elements resistance will not change. So if the voltage drops then the current will drop, and vice versa.

Ohms law, R (the element resistance) is the one that will not change. I = V/R

It's Ohm's law - I = V/R

R is fixed so as V gets lower, so must I.

You can think of it as the voltage pushing the current through the resistance. A lower voltage means it pushes less current through.

If you run some examples with say a resistance of 10ohms and voltages of 240 and 220, you'll see the current drop.

Edit: beaten to it!

Ok, I accept the weight of opinion and I'm off to google until I've got my head around this

On this basis then, lower voltage would mean lower amps so that the element would put out less heat?

My confusion comes from us once plugging an electric pool heater made in the UK, into a 220v system overseas and the cable quickly overheated. Why didn't the cable stay cool and the heater simply perform less well than it would at 240ish volts? It was a ~56a heater of a 63a supply.

 

[Jim_e_Jib]

Ok, I accept the weight of opinion and I'm off to google until I've got my head around this

On this basis then, lower voltage would mean lower amps so that the element would put out less heat?

My confusion comes from us once plugging an electric pool heater made in the UK, into a 220v system overseas and the cable quickly overheated. Why didn't the cable stay cool and the heater simply perform less well than it would at 240ish volts? It was a ~56a heater of a 63a supply.

Yep, that's right-lower voltage and lower current would mean lower wattage and less heat output.

I'm not sure about your pool heater - maybe the cable just wasn't able to handle such a high current or perhaps there were other factors involved - damage in transit? Was this for the aquarium...?

 

[Deuce]

Yep, that's right-lower voltage and lower current would mean lower wattage and less heat output.

I'm not sure about your pool heater - maybe the cable just wasn't able to handle such a high current or perhaps there were other factors involved - damage in transit? Was this for the aquarium...?

Not for the aquarium, but for a temporary pool so same thing..

The heaters are in regular use and are tested and still perform well. It was just that one location where both heaters struggled.

They became electrically hotter than they should around the cable entry. I can't accurately say if they heated the water more/less efficiently than normal as the issue was detected, and both disconnected too soon to make any judgement on that.

 

[telectrix]

if the element is OK, then overheating of the cable in the shower could be down to a high resistance termination, either between the cable and crimp or crimp and terminal.

 

[Ampo]

Need to dust off the old books, I think I was getting confused with the amp thing as I would be calculating say the 9.5kw of the shower where of course ohms law throws that out the window because the 9.5kw is only relevant to the expected supply voltage so less voltage less kw less amps. Have I got there