Electrical test procedure on a gas boiler

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Here is a typical heating circuit.
Bear in mind that before the switch (and CU) the N & E are connected together and
in the boiler are multiple circuits which in a combi will include the pump and valve.

512px-Y-Plan-Wiring.gif
 
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You are reading from the line conductor through the element to the neutral, which is connected to earth as said.
 
M

martineire

Prentice Boy how do you test PSC, Zs or Ze? Do they need a meter?

Yes a meter would be required.
I did add it was a rhetorical question as personally I do know how to do the tests (unless they have changed since I retired about 5 years ago. May well have done I admit).

Point I was trying to make was many gas men don't possess even a cheap multimeter and even those who do, have little knowledge of how to use!
Can you pm me info on the correct test procedure so, if you have any handy or point me in the right direction to obtaining some.

Because apparently the likes of theses tests is a load of ****

http://boilerfaultfinder.com/electrical-safety-checks/resistance-to-earth/

http://boilerfaultfinder.com/electrical-safety-checks/short-circuit/

http://boilerfaultfinder.com/electrical-safety-checks/earth-continuityttest/

Thanks
 
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resistance-to-earth
This test merely shows that there is no connection between L & E, which, obviously there should not be.
It could equally be done at the FCU or plug.

short-circuit
This one is just WRONG as you have discovered (183Ω) as there will be some connection between L & N in an appliance, e.g. oven element or just a lamp.
Also, a 'dead short' would give a reading of <0.05&#937; and immediately blow the fuse when switched on.
Plus, of course, with PCB control in the boiler none of the parts will be switched on when the power is off.

earth-continuity test
This test is the useful one to ensure that the boiler carcass is earthed.
Further testing should establish that the Circuit Protective Conductor (CPC - earth wire) itself is actually connected to the Earthing of the installation (your 0.7&#937; virtually does this).
 

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