Help me understand what happened

[sancycling]

I'm not sure this is where I should post my question but I'm sure many electric gurus can help me out.

So I was brewing this sunday and fell behind schedule for my second batch so I thought it would be a good idea to shorten the time for heating my strike water using an aluminium heating element. I use this element to adjust my mash temp in case I'm off by a couple of degrees.

My HLT is a 7 gal aluminum pot. I put the element in the water and then plugged it in. After 15 seconds or so I hear a loud bang and see a flash. Immediately I unplugged everything (the breaker was tripped). But I realized the pot now had a leak. It seems that something went wrong and the electric arch perforated the bottom of my pot.

What went wrong? What was my mistake?

Thanks. I just want to make sure I don't put my safety at risk or my electric installation.

 

[augiedoggy]

I'm not sure this is where I should post my question but I'm sure many electric gurus can help me out.

So I was brewing this sunday and fell behind schedule for my second batch so I thought it would be a good idea to shorten the time for heating my strike water using an aluminium heating element. I use this element to adjust my mash temp in case I'm off by a couple of degrees.

My HLT is a 7 gal aluminum pot. I put the element in the water and then plugged it in. After 15 seconds or so I hear a loud bang and see a flash. Immediately I unplugged everything (the breaker was tripped). But I realized the pot now had a leak. It seems that something went wrong and the electric arch perforated the bottom of my pot.

What went wrong? What was my mistake?

Thanks. I just want to make sure I don't put my safety at risk or my electric installation.

wow sounds like you had one of the elements wired wrong and it or the pot had electrical current going through the housing of the element... they arched when one touched the other. may I ask if you have the system properly wired to a GFCI because it certianly doesnt sound like it (it would have tripped as soon as the element touched water)..... your lucky you didnt get electrocuted.

 

[sancycling]

This is the type of element that I'm using. There is nothing to wire, just plug it to the wall 110V

 

[JustLooking]

That thing is scary. Not even a ground wire. I believe those things are made for heating cups of water not large volume. In the case of large amounts of water you should be plugging into a GFCI outlet. How deep do you put it into the water?

 

[sancycling]

I bought this thing in Home Depot. $4.50.
It is about 8 inches long... I had about 1 1/2 inches exposed, just like I do when adjusting mash temp.
I had it about 2 inches from the bottom of the pot.

I agree that it is not designed to heat large volumes of water, but it should work to increase a few degrees or help the gas burner.

And as you said it has no ground wire.


Enviado desde mi iPhone con Home Brew

 

[grathan]

You need a gfci outlet when putting electricity near water.

 

[augiedoggy]

You need a gfci outlet when putting electricity near water.

Or in it as in this case... im not sure if it had anything to do with it but I would be checking the polarity of your wall outlet.

 

[Call_Me_Tex]

Or in it as in this case... im not sure if it had anything to do with it but I would be checking the polarity of your wall outlet.

It's a simple resistive element... polarity doesn't matter.

 

[ajdelange]

The only thing to do post mortem that I can think of is to do an ohmmeter check between the blades of the plug and between each blade and the aluminum coil. Presumably you will see an impedance of less than half the blade to blade impedance between one blade and the aluminum. Toss the thing in the garbage.

 

[augiedoggy]

It's a simple resistive element... polarity doesn't matter.

Ahh yes I should have realised that.... too much home brew while posting last night.

 

[Facinerous]

That is most certainly scary and a perfect example of why we should always use a GFCI. I have a guess to what could have happened.

Since you have a nice fresh hole in your HLT it sounds like you found your fault current path. Somehow your pot became grounded, whether this is intentional or not I don't know but if you are using a heat stick in a metal pot it should be grounded.

My theory is, and the big reason for use of a GFCI, what if your hand held heating element became cracked? Most of these elements that I am aware of has a ceramic layer sandwiched in between two layers of metal. One that does the heating, then ceramic insulator, then metal sheath.

If it cracked in some way then when your liquid crept into the crack, over time, your little electron buddies found a better path to ground rather than go all the way through your intended path. Result, a fault, a hole in the pot, and a tripped breaker which I can say at least thank god for that.

 

[sancycling]

Thanks all for the replies and theories.

Even though I'll never know what exactly happened, I definietly learned a few things.

1) Toss the heater
2) Install GFCI outlets in my kitchen. Makes sense just in case.
3) Next time I put something electric in water, I'll make sure it is safe and always use a CFCI outlet in that case.

I appreciate all your help.