Economy 7 immersion heating problem

[chriscole943]

Hi, attended a job today where the client said that the E7 element isn't working, no hot water in the mornings. I turned off the daytime element and I put a plug on the flex of the nightime element, plugged it in and I could hear element start to heat. Left it on to see if it would click off with thermostat and it did a little while later. I checked the radial circuit supplying it from the E7 board, L-N-Cpc continuity all ok. Checked IR and again all ok. Checked mcb, ok. Checked 20A switch and again ok. I can only assume problem on E7 timer and asked client, she's adamant E7 works because the storage heaters were working. I checked the element again by turning heat adjust screw to full and thermostat clicked and again element started to heat. I was able to access the E7 timer and clicked to on and it come on. I've left it by putting a single socket on that circuit with a plug in tester in it and told the client to listen later to see if the E7 timer is actually working. I was wondering if anyone has had prob like this and have I missed anything. I haven't been paid for this or other works I did today and would like to get it sorted. I haven't posted on here before but look in regularly, lots of good advice, guidance and banter. Sorry for long post but.
Any suggestions welcome

 

[Stocksie]

I think you've covered everything there so I'd say the E7 timer. Did u continuity test the flex ?

 

[GarryJ]

Sounds like faulty E7 Programmer/timer. Could you rig up a temp supply at the DB to feed the full E7 circuit then it would allow you to test the programmer by fast forwarding the timer?

 

[chriscole943]

Flex is ok. And there was no programmer on that circuit. It comes from E7 board 20amp mcb into 20amp switched outlet, out to flex to element.

 

[chriscole943]

I did get temp supply to board to liven circuit and all ok????? Going back in morning, and hopefully getting paid.

 

[ayjay]

how do you know the immersion is actually heating the water?
you say you can hear it "start to heat"
if an element in an immersion starts to heat theres no noise
if its split there IS noise, a bubbing sound--no heat
btw the nightstores are on separate breakers the immersion has sweet f/a to do with them

 

[chriscole943]

Don't know what you mean by split? But what I meant was it sounds like a kettle element. I left it plugged in for an hour and it heated the water. I just went and turned on the immersion at mine and its making the same sound.

 

[chriscole943]

I know the night stores are different but there is 2 elements, day & E7 night. The night element is supplied from its own mcb in the E7 board.

 

[ayjay]

hi chris, sometimes the element splits open inside the cylinder and just bubbles due to the current escaping into the water
but if its actually heating the water , it must be a Supply problem

 

[Dave Dee]

I would say you have covered everything. Perhaps your customer had run off all of the hot water in the tank and then thought that there was a problem when only cold water was running through the system. If your test lamp lights, then all should be OK.

 

[Sav]

Hi, attended a job today where the client said that the E7 element isn't working, no hot water in the mornings. I turned off the daytime element and I put a plug on the flex of the nightime element, plugged it in and I could hear element start to heat. Left it on to see if it would click off with thermostat and it did a little while later. I checked the radial circuit supplying it from the E7 board, L-N-Cpc continuity all ok. Checked IR and again all ok. Checked mcb, ok. Checked 20A switch and again ok. I can only assume problem on E7 timer and asked client, she's adamant E7 works because the storage heaters were working. I checked the element again by turning heat adjust screw to full and thermostat clicked and again element started to heat. I was able to access the E7 timer and clicked to on and it come on. I've left it by putting a single socket on that circuit with a plug in tester in it and told the client to listen later to see if the E7 timer is actually working. I was wondering if anyone has had prob like this and have I missed anything. I haven't been paid for this or other works I did today and would like to get it sorted. I haven't posted on here before but look in regularly, lots of good advice, guidance and banter. Sorry for long post but.
Any suggestions welcome

Hi Chris,
Sorry to sound like a dunce, but can you explain the procedures again for testing, as I sometimes come across E7 with similar problems, but not sure on testing procedures.
thanks again and sorry to sound thick !!!

Sav

 

[chriscole943]

I just did the basics to check the circuit was ok . Continuity end to end of L-N-CPC, then did Insulation resistance tests between all 3 to check integrity of cables. Reinstated, put temp supply on, checked polarity. All ok.

 

[chriscole943]

Thanks Ayjay, didn't know that about a split element.

 

[jibjob]

Hi, IR the element, if you see lots of zero's it's knackered. Continuity should be about 18/19 ohms across LN. When you say E7 timer do you mean at meter ie time switch etc, or is it local to hot water cylinder?

 

[chriscole943]

Thanks I'll IR and continuity when I go back tomorrow. The timer is at meter.