Yes, I understand that. However, as you saw, what I was commenting on was the fact that the advice very commonly given to posters in this forum (and other places) is that they should not take seriously an 'electrician' prepared to undertake a CU change without a prior PIR/EICR, that 'no real electrician would do that' etc. etc.The problem is, John, to do a full EICR first, you will be required to complete a 'schedule of inspections' and a 'schedule of test results.
Maybe we're being too literal in talking about the 'prior EICR'. There is, as you say, little point in producing an 'EICReport' (the bits of paper) on the pre-change installation. However, can you not do all the inspection and testing (other than those few things which are CU-dependent) prior to the CU change, but then only document the results (together with results of the post-change live tests and a few bits of inspection) after the CU change (plus, of course, any other post-work tests on any work you may have done in addition to the CU change)?This EICR is on the existing installation, which includes the existing CU, (and protective devices etc), it would take you most of the day on an average 3 bedroom semi, cost the customer an additional £100 to £200 and it wouldn't be worth the paper it's written on the day after, when you change the CU.
You would then have to complete an EIC for the CU swap - with accompanying 'Schedules' - granted, you will transfer some of the results, but what a waste of time.
Kind Regards, John.
If the existing CU is obviously ancient, I walk away if the customer won't have an EICR. If this shows any serious faults, the customer has a choice of going ahead or leaving as is. Changing over and then finding faults means the spark can't complete the job until these are resolved.
Not the best way to enhance your chances of getting any referrals.
I was caught in my early days, when I changed a CU and then started testing and lost a couple of days fixing wiring faults before I could commission the new CU. The customer was furious and I decided then I'd never get caught again.