I am replacing an electrical triton shower in a bathroom for a identical make of shower and need to know if you now have to get a electrical certificate and sign off once complete. 

Isn't commissioning such a unit according to the manufacturer's installation instructions a sufficient test?
Yes.Would you re-test the circuit to the shower?
what tests would carry out after replacing a shower unit with one of an identical brand and power rating?
The same is true of a kettle.If the old unit was defective it may not have been taking full load when used.
Let's say that you find a voltage drop of 12/240V in a cable of seemingly adequate capacity but of hidden and unknown run length.So I would measure voltage drop along supply cable to determine that the cable was not liable to overheating at the full load of the fully functionally new unit.
I'm confused.That would not show any hot spots such as changes in size of the cable along the run from the CU ( visible inspection needed ) but is better than assuming the cable is OK.

I will agree there are many different definitions of fixed and temporary one of course being use of screw or nail. But in this case I am looking on page 9 of Approved Document P h. where it states even where connection is by a 13A plug and socket. To get a definition of fixed you need to look in the in-service inspection and testing of electrical equipment which for fixed says "This is equipment or an appliance which is fastened to a support or otherwise secured in a specified location" which to my mind would include screws or nails unlike the legal definition used to determine ownership.@ericmark - you use the terms "fixed installation" and "temporary installation", and you say that there's a difference between them, but where are these terms defined and where is the difference defined?
Yes that is true even if most people would not bother it is what it says on page 9. However there is a second document which does not seem to say exactly the same and one could try wangling out of this requirement but in any case that is not the issue here.And when you say "completion certificate", are you saying that fixing an extension lead flex and a multi socket into a kitchen is work that's notifable under the Building Regulations?
And you say that you pesonally record test results, what tests would carry out after replacing a shower unit with one of an identical brand and power rating?
Isn't commissioning such a unit according to the manufacturer's installation instructions a sufficient test? Would you re-test the circuit to the shower?
An extension lead isn't equipment or an appliance.To get a definition of fixed you need to look in the in-service inspection and testing of electrical equipment which for fixed says "This is equipment or an appliance which is fastened to a support or otherwise secured in a specified location" which to my mind would include screws or nails unlike the legal definition used to determine ownership.
Page 9 is irrelevant. The entire Approved Document is irrelevant.Yes that is true even if most people would not bother it is what it says on page 9.And when you say "completion certificate", are you saying that fixing an extension lead flex and a multi socket into a kitchen is work that's notifable under the Building Regulations?
I have no idea what you mean by all that.However there is a second document which does not seem to say exactly the same and one could try wangling out of this requirement but in any case that is not the issue here.
It doesn't "happen" in the middle of a shower replacement job that I do.I would always do an earth loop impedance test it is the only way I can be sure the earth is intact. I have found in the past a nail had been knocked in dead centre of the cable and so even when the installation looks A1 there can be problems. And of course insulation resistance I know you should not have JB's in walls but it does happen.
So why, when you so much as touch even one screwdriver in an unknown installation, do you not carry out a full inspection and test for all circuits? Why just the circuit that the shower you're replacing is connected to?And I jacked one job fitting cookers because he would not give me time to test cooker outlet before connecting up new cooker. So actions speak louder than words yes I would test.
At 57 and worked around the world I have seen many installation which look A1 and are not and I don't take anything for granted. Although you may be changing like for like unless you have the Minor works cert from last change how do you know what was fitted is what the system was designed for the shower you are replacing may not be the original.
I found one with a low prospective short circuit current so looked further and found the 10mm was joined to 2.5mm in the ceiling space and it had originally been a power shower in loft space and someone had changed it for a standard electric shower and changed MCB? Had I not tested on regular basis I may have missed that. When you test all the time you know what results to expect so a fault like that rings alarm bells but if you don't do it regular then you can easy miss things that are out of ordinary as they may still be within spec.

There are two laws which effects us the building regulations and electricity at work act.
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