Testing Immersion Heater

[armyash]

I went to a job today, the customer didnt speak any english but i spoke to her boyfriend on the phone. Said they have not much hot water. I tested the immersions to make sure there was power going to them and was only getting a reading to the bottom one at first. Double checked and there was power to both.

I then disconnected the wires from the immersions and checked continuity across the connection points, is that correct? What should my multimeter be displaying?

What other tests can I do.

If someone can PM me a simple step by step guide that would be great. 😀

For what it's worth, she turned the switches for the immersions off as I left, I tried to say she might want them on but she said 'no, it's ok'.

Maybe she thinks turning them on for 5 minutes before a shower is sufficient to get hot water??

 

[BLOD]

approx 18 ohms across element terminals and no reading between element & earth post would suggest element is ok.
Not that accurate but with just a cheap multimeter it's served me well.

 

[BLOD]

forgot to say- there's a lot of cheap thermostats about at the moment - so maybe just check continuity across the stat

 

[armyash]

approx 18 ohms across element terminals and no reading between element & earth post would suggest element is ok.
Not that accurate but with just a cheap multimeter it's served me well.

Thanks that's what I was getting. Could feel the immersions heating up anyway so should be ok. If not I will be back there tomorrow or next week.

 

[GasmanxxxR1]

unless the whole thing is scaled up and just has a smaller volume of actual hot water in it

 

[stevetheplumber]

ive never had a figure for resistance thanks for that, generally i expect resistance across the element and check there no continuity from live and neutral terminal to the cylinder its amazing how you can have an element thats split wide open sitting in the water and still working i quite often just use a neon first off to see at what point theres no power

 

[mikegas]

Ohms law, a 3kw immersion would be 3000W ÷ 230V= 13Amps. 230V ÷ 13Amps = 17.7Ohms

 

[zeebeedee]

forgot to say- there's a lot of cheap thermostats about at the moment - so maybe just check continuity across the stat

Put one in last month in blew in 4 days!