Danger Of Undersize Wiring For Storage Water Heater

[doggydo 0]

Thought it was good idea to remind forumers to check their water heater wiring.

Recently, my water heaters stop functioning and the electrician traced it to a burn up junction box.

The junction boxs was replaced but it burn out again in a couple of days.

Instead of calling the electrician this time, I check the problem myself.

Found that

A. Heater was supplied with severely undergauge wire. Storage water heater required a min wire gauge of 70, size 40 was used.

B. Thermostat was not properly set.

These nearly cost a fire in my house as evidently, the junction box was melted and the circuit breaker did not trip.

It is very easy to check for undersize wire, turn on your heater, touch the supply wire, if it feel hot, undersize wiring is used. It should not feel hot in any circumstances.

Thermostat should never be set above 100degree celsius. Water will not boil above 100degree. The heater will not stop running even when water is boiling - not only run up your electric bill but also an explosion risk if the pressure relief valve is blocked.

You cannot tell the wire gauge by looking at the wire insulation, size 40 or 70, the insulator thickness is the same and the gauge size on the insulator may not be correct either.

[h4happy 1]

I was about to post this matter too.

Mine is the water heater, it has the current that flow thru' the water heater. But produce no warm water/hot water.

Check using testpan and found out that all has current.

Initially thought that the water heater has spoilt but then I just bought it less than 3 month old.

So, engage my neighbour and he check for me and found out the severely undergauge wire at the junction box. My friend cut off that piece of wire and have a new wire gauge and woala! The water heater ok!

So, for those out there, if experiences no hot water and there is current, check at the junction box for any burn out. It might save you money if you engage a electrician to check or the supplier (transport charges).

[hihihi 0]

my instant water heater also having same symptoms. It started off working after install. After I recently shifted in, now turn ON, LED don't light up, no hot water either.

I opened up, tested the "live" wire has current. My current setup is a wire come out from the wall (done by HDB), then connect to the inside of the water heater.

Can post some pictures? What is a junction box? I'm an amateur, hoping either getting the warranty guy come down or if can DIY also can.