boiler breakdown tips from training centre

[lordyjordy111]

Hi all

I recently went to woodys training and would like to know if anyone uses this test with success

he said place multimeter on ac current

unplug boiler (if on plug)

then place probes between live and earth terminals (in boiler)

then between neutral and live terminals

then between neautral and earth terminals

all should read between 0.1mv and 15mv

if all three fail (ie all out of range) then there is a fault with a major component (pump fan gas valve)

does anyone use this test?

 

[Nostrum]

Never heard of that before, checking resistance would indicate a short, but voltage on an appliance that is disconnected, not heard of that one.

to be honest though, you'd already know there was a fault on the boiler. Because that's probably the reason you've been called there in the first place!

 

[lame plumber]

no,,,,,

 

[glenno1]

A strange test that 1 imo

 

[Killy Bing]

........thats basicly safe isolation on something that is unplugged ?

 

[glenno1]

You should not test safe isolation with a multimeter or am i missing something

 

[lame plumber]

You should not test safe isolation with a multimeter or am i missing something

how else would you test isolation is ok, tongue or finger

 

[plumber0808]

how else would you test isolation is ok, tongue or finger

Yep finger sort of wafting around it until I'm brave enough to go for it.

 

[lordyjordy111]

no its not to verify isolation... its to check quality of earth connection as well as indicating what is actually wrong with the boiler, or so im told

voltage comes from batteries in multimeter btw

 

[Mike Jackson]

how else would you test isolation is ok, tongue or finger

You should use a battery free voltage tester that is checked on a known live source or with a proving unit before and after the test. A multimeter can give false readings.

 

[glenno1]

Thank you lordy and mike

 

[Billy Bob Bob]

Hi all

I recently went to woodys training and would like to know if anyone uses this test with success

he said place multimeter on ac current

unplug boiler (if on plug)

then place probes between live and earth terminals (in boiler)

then between neutral and live terminals

then between neautral and earth terminals

all should read between 0.1mv and 15mv

if all three fail (ie all out of range) then there is a fault with a major component (pump fan gas valve)

does anyone use this test?

no furthermore you should have been told to test your leads for continuity first,how do you know a circuits really dead if you have a broken test lead?

 

[lordyjordy111]

he did tell me that to be fair gas man, just didn't put it in my post

anyone else been on this course??

all the courses I go on seem to go over the same stuff..... a lot of theory and not a lot of practical

how did everyone else learn the breakowns?

 

[glenno1]

For dead testing (safe isolation)you need a two pole voltage tester

 

[happyflyer]

You should use a battery free voltage tester that is checked on a known live source or with a proving unit before and after the test. A multimeter can give false readings.

1000% right boilers or not on boilers, you will still need your mutil-tester if you are testing for ionization currents or resistance of thermistors, but for straight testing for full isolation from the mains I would advice none fully trained electricians to only use plain simple probe tester and you must test it on a known live supply close to the boiler you are working on, and do not drop the tester on the way to test the boiler.

BTW Screw-fix do a plug tester that allows you to test the power out of a socket outlet there you can test your tester.




Make sure your probes go inside the holes and your tester lights up on the correct voltage range L to N don't be tripping the main RCD, your a plumber not an electrician and you never will be!!!

 

[glenno1]

You can adapt a shaving socket for proving unit

 

[happyflyer]

You can adapt a shaving socket for proving unit

Explain please, getting an electric shock is serious stuff!!!!

 

[AWheating]

the safest solution is to use a proving unit with your approved voltage indicator.sometimes using a socket as your known source can have its own issues, you do not know if this socket is safe or wired correctly and many voltage testers can when testing between live or neatural to earth trip the rcd's at the board.

isolate and lock off
test your voltage indicator
test for voltage
test your voltage indicator

 

[AWheating]

no its not to verify isolation... its to check quality of earth connection as well as indicating what is actually wrong with the boiler, or so im told

voltage comes from batteries in multimeter btw

i cant see how this would check quality of earth connection, if you remove the plug from the socket you have removed the appliances earth path. Continuity would allow you to look for shorts to earth at the plug.

 

[happyflyer]

It worries me a bit, this lack of general electrical knowledge, maybe sparks should learn plumbing, it might be easier and save lives..

 

[AWheating]

It worries me a bit, this lack of general electrical knowledge, maybe sparks should learn plumbing, it might be easier and save lives..

most the sparks i know dont do safe isolation correctly, and most cant wire a plan correctly either. Ask a sparks where his/her proving unit is and they will say its in the van somewhere

 

[stoker122]

Isn't that test for earth resistance, correct voltage and correct polarity, but should be live when tested?

 

[glenno1]

take red plastic bit out of shaving plug,then when you plug it in you have a proving unit for your probes,not ideal i know but it works