BS7671 test and internal electric heating

[Soup]

Hi all
I'm unsure if it's appropriate to post this on this board but I wanted to get opinions from people in the industry on a sticking point with an electrician I currently have.

a bit of background - I am letting out my flat and as part of the pre-let safety checks I decided to go ahead and get a "periodic test" carried out on the flat - a test under BS7671 on the internal electrics.

The electrician did the report and said the circuits were satisfactory, supplying me with an EICR on completion.

On the report, it stated he was unable to test 2 things :
1) The off-peak water circuit, as there was no power on the circuit due to it being tested during the day. I was fine with this...; and

2) The central heating circuit. I have Flexel Ceiling Heating in the flat and was quite specific about asking him to test this from a safety point of view. He said as there were timers in the circuit he was unable to test this (I have two 24-hour "pin-controlled" timers on the hallway wall).

The central heating point is where I am having the issue. Following further discussions, he said that as well as the issue with the timers, the heating did not seem to be powered as it was being fed from a night-time supply, external to my flat.

This struck me as a bit odd - I know my heating works (a friend of mine went to the flat on my behalf to test it after the electrician had done the BS7671 test and said it seemed to work fine) so I'm a bit puzzled why he couldn't test the heating circuit. Maybe the night-time supply could be explained by Economy 7?

The electrician also said he couldn't work out how to turn the heating on as well - so surely if he had actually turned the heating circuit on (there's a main on/off switch on thermostat in the lounge of the flat) then he should have had some sort of electric current reading to confirm whether it was satisfactory within the boundaries of the BS7671 test?

His final reply to me recently was:
"I offered a ‘Periodic Test’ of the flat’s electrics as prescribed by BS7671. This is a test of the various circuits, specifically earth loop impedance and insulation resistance. This testing does not include appliances, and also excludes central heating (systems) which is effectively an appliance.
The power circuit cable from the consumer unit in the hallway goes straight into the timer boxes and these appeared to be preventing that circuit from being tested. There is no requirement under BS7671 to have to dismantle apparatus in order to test which appears to be the case here.

As I said, all other circuits check out fine, and on the basis that this circuit is of the same vintage, and nothing has been modified, there is absolutely no reason to be concerned.
So if you have an absolutely specific cause for concern about the ‘circuit’, then that would be a separate piece of work, and wouldn’t come under the remit of ‘Periodic Testing’.
If it’s the case that you want a general central heating service/ health check, then this is something that is definitely outwith the scope of periodic testing, and is not a service I can offer."

What do you guys think - is he fair in his comments, or he is simply trying to avoid having to going back to test the circuit again with the heating switched on to see if it would have a different result? He seems like a stand-up guy and the other work he has done for me has been fine to date.

Thanks in advance :army:

 

[Darkwood]

Hi Soup and welcome to the forum from the staff

 

[HappyHippyDad]

Hi Soup,
I would personally have a good chat with the homeowner before undertaking the EICR so that you know exactly what you are getting from me and we avoid these kind of scenarios. However, it sounds as though you did mention the central heating before hand.
An EICR generally takes around 3/4 (approx) of a day to complete (based on a 3 bed property) and then another hour (at least for me) to complete all the paperwork.
I would test the Insulation resistance on the central heating, along with one or 2 others tests which it sounds as though he did (these are dead tests, completed with the power off). This would be a test to see if all the wiring upto the boiler is ok. I would not be testing your combi boiler (or whatever appliance it is) iitself.
My instinct is to think he's done an OK job but there has been a lack of clear communication.

 

[davesparks]

If you specifically asked for it to be tested before he started/took the job on then he should have tested it, regardless of what would normally be included in periodic testing.

Pin type timeswitches operate mechanically rather than electronically and almost always have an override control, or failing that just adjust the time to turn it on!

'Dead tests' (those requiring the supply to be isolated) can be carried out on the off peak circuits exactly the same as normal circuits.
Depending on the nature of your off peak supply it is almost always possible to carry out the live tests without the off peak supply being live

 

[Soup]

Thanks very much for the responses guys, really appreciate it.

I should have clarified that my property does not have gas, it is purely electrical from a power point of view so no boiler, simply water tanks.

I did have a detailed chat with him beforehand about the heating system - although I wasn't asking him to test the functionality of the heating itself and whether it was in good working order, I merely wanted to ensure the electrical circuit that related to the heating (and other in-built appliances such as extractor fans) was tested - and from our discussions I thought that it would be.

He's basically said that he couldn't test this particular circuit due to the timers and also because of the lack of power - which is why I queried it with him when my friend said the heating was working fine, there must have been power for it to work - so surely turning it on when testing it would have solved this issue, unless the timers in the circuit prevented this BS7671/EICR test irrespective if the heating was on or off.

The comment from one of your replies : "Pin type timeswitches operate mechanically rather than electronically and almost always have an override control, or failing that just adjust the time to turn it on!"
is what it comes down to - my underlying feeling is that he couldn't/didn't work out how to turn the heating on, thus no power to test that circuit properly - something which could have been rectified by a quick phone call to me asking how to turn the heating on!

Based on the above, do you think I should leave it or push this further?

 

[Richard Burns]

I would feel that the electrician has completed a normal periodic test of your installation.
However if the heating circuit was specifically agreed as being part of the testing this should have been included (up to the point of the timers).
It sounds like he was having difficulty with this part of the installation and from what he says I would not be confident that he would be able to complete this part of the testing.
I would tend to agree that if the installation is compliant in other respects that the heating could probably be complaint as well but if you have a specific concern about it then it may be a solution to get someone else in for an hour to cover that circuit on its own.

 

[Soup]

I would feel that the electrician has completed a normal periodic test of your installation.
However if the heating circuit was specifically agreed as being part of the testing this should have been included (up to the point of the timers).
It sounds like he was having difficulty with this part of the installation and from what he says I would not be confident that he would be able to complete this part of the testing.
I would tend to agree that if the installation is compliant in other respects that the heating could probably be complaint as well but if you have a specific concern about it then it may be a solution to get someone else in for an hour to cover that circuit on its own.

Thanks for that - it might indeed be a good idea to get someone else out just to look at the circuit(s) he couldn't test properly.

Interestingly, I have since found an electrical test report which I had done when I bought the place in 2008 - seems to be the same type of test (Periodical Inspection Report under BS7671). The electrician who did that test at the time managed to do a full test of all circuits, including the heating - so I'm going to send it to this other guy and ask him "if he could do it, why can't you?" (although I'll try to word it more politely than that!) :laugh3:

 

[Soup]

Right, I think I've nearly got to the bottom of this with the electrician now.

When I asked him about the various differences between the 2008 report and his, he noted the following:

- The 2008 report showed a very low (almost non-existent) for insulation resistance on the heating circuit - which would seem to imply that the other electrician also struggled to get a meaningful reading (or any reading at all) out of that circuit;

- The 2008 report did however show what appears to be suitable Zs readings for the heating circuit and the off-peak water, something which my current electrician hasn't able to manage. He's unsure how the previous electrician would have got such a reading given the lack of power and the switches/timers (ie isolation) in the circuit;

- I also queried why he hadn't tested the continuity (Ring final circuit continuity in respect of the "sockets" circuit, and R1+R2 continuity for all circuits) in his report, when the previous electrician had. His response was "There’s no need to do continuity testing on a periodic. If the testing of Zs and Insulation Resistance gives good results, then that really proves a safe circuit which is the aim of the exercise. BS7671 merely states to undertake ‘appropriate tests’. If another sparky chooses to do continuity, that’s up to him but it’s always down to discretion and appropriateness."

So his stance on the heating circuit seems to match up with the outcome of the 2008 report.

I'd be grateful if any of you have any comments on the 2nd point (regarding the inability to test Zs) and 3rd point (whether continuity testing is/isn't part of a periodic test)!!

 

[Richard Burns]

If there is no power to a circuit then for a periodic test this should be noted in the limitations section.
In this case it would be usual to do a R1+R2 test or an R2 test on the dead circuit to confirm protective conductor continuity, from these results and the Ze a Zs value may be calculated.
For your circuit in 2008 it may be that the Zs was calculated up to the point of the timers, if there is the possibility of gaining access to the conductor connections.
For periodic inspections there is no requirement to test the protective conductor continuity for a circuit if there is a valid Zs reading obtained as the Zs reading confirms protective conductor continuity. A lot of electricians will do the R1+R2 test or R2 test as this is part of initial verification and is very familiar and provides a secondary confirmation that there is a protective conductor present with low conductivity.

 

[newtothis]

Maybe you could contact the manufacturer, they might have some kind of list of approved testers for your ceiling heating system ?
Personally think you're flogging a dead horse pursuing the spark over this, if that's your angle, not sayin' it is of course.





Edit - corrected it for you ...Darkwood

 

[HappyHippyDad]

Right, I think I've nearly got to the bottom of this with the electrician now.

When I asked him about the various differences between the 2008 report and his, he noted the following:

- The 2008 report showed a very low (almost non-existent) for insulation resistance on the heating circuit - which would seem to imply that the other electrician also struggled to get a meaningful reading (or any reading at all) out of that circuit;

- The 2008 report did however show what appears to be suitable Zs readings for the heating circuit and the off-peak water, something which my current electrician hasn't able to manage. He's unsure how the previous electrician would have got such a reading given the lack of power and the switches/timers (ie isolation) in the circuit;

- I also queried why he hadn't tested the continuity (Ring final circuit continuity in respect of the "sockets" circuit, and R1+R2 continuity for all circuits) in his report, when the previous electrician had. His response was "There’s no need to do continuity testing on a periodic. If the testing of Zs and Insulation Resistance gives good results, then that really proves a safe circuit which is the aim of the exercise. BS7671 merely states to undertake ‘appropriate tests’. If another sparky chooses to do continuity, that’s up to him but it’s always down to discretion and appropriateness."

So his stance on the heating circuit seems to match up with the outcome of the 2008 report.

I'd be grateful if any of you have any comments on the 2nd point (regarding the inability to test Zs) and 3rd point (whether continuity testing is/isn't part of a periodic test)!!

With regards your first point, an insulation resistance reading is a dead test (conducted with power off) so your electrician could have done this test, I am unsure if he did or not? Also, a low insulation resistance result does not mean that he had difficulties obtaining the result, it means he tested it and that was the result he got. A result of 1MΩ or greater is acceptable, and a result of below 1MΩ means that circuit requires attention.

With regards your second point (the Zs readings) as Richard has said the original electrician may have just calculated this from looking at the Ze result and adding it to the R1+R2 result (so it could be obtained with the power to the heating circuit off). You could perhaps look at these 2 results (Ze and (R1+R2)) and if added together equal 'exactly' the result he has put for Zs then he 'may' have just calculated the Zs (unless coincidentally that was the measured Zs, but unlikely). Ze may be written as 'Zs at DB' on the report that you have.

So, with the power to the heating off your electrician would not be able to carry an actual 'measurement' of the Zs, but he could carry out an R1+R2 of this circuit and add it to the Ze (to obtain a calculated Zs).

Again, as Richard has said not all electricians will carry out a R1+R2 on a report if they get a satisfactory Zs so i dont think your electrician should be penalised for this, but an R1+R2 on the heating circuit would have been necessary as no Zs was obtained.

Lastly, it's very difficult to give 100% guaranteed advice without seeing the installation.

It would be interesting to know how long the electrician was there for and how much he charged?

 

[Risteard]

To get this into perspective, it is not a "periodic test". It is a periodic inspection. Inspection precedes testing, and is the more important aspect. (Many problems will not be located through testing.) The testing merely supplements the testing.

Also, I presume happyhippydad did not mean to suggest that an insulation reading of 1 Ohm would be acceptable!

 

[Leesparkykent]

To get this into perspective, it is not a "periodic test". It is a periodic inspection. Inspection precedes testing, and is the more important aspect. (Many problems will not be located through testing.) The testing merely supplements the testing.

Also, I presume happyhippydad did not mean to suggest that an insulation reading of 1 Ohm would be acceptable!

??????

 

[HappyHippyDad]

To get this into perspective, it is not a "periodic test". It is a periodic inspection. Inspection precedes testing, and is the more important aspect. (Many problems will not be located through testing.) The testing merely supplements the testing.

Also, I presume happyhippydad did not mean to suggest that an insulation reading of 1 Ohm would be acceptable!

Thanks for pointing that out Risteard! How embarrassing! Have amended.

 

[Risteard]

??????

LOL. I meant the testing merely supplements the inspection!

 

[GEOFF S]

The central heating system will fall outside the scope of BS7671 try BS EN 14336:2004. The fixed wiring upto the controls/? will be under BS7671

Cheers

 

[Leesparkykent]

The central heating system will fall outside the scope of BS7671 try BS EN 14336:2004. The fixed wiring upto the controls/? will be under BS7671

Cheers

It's not a water based heating system.

 

[GEOFF S]

It's not a water based heating system.

Thanks Lee, just saw central heating. That said, this productt will have its own product standard to which it needs to de designed, installed, commisioned and tested.

Cheers

 

[Soup]

Thanks everyone for your comments on this. It's quite confusing as a layman with no electrical knowledge/training so I'm trying to get up to speed here!

With regards your first point, an insulation resistance reading is a dead test (conducted with power off) so your electrician could have done this test, I am unsure if he did or not? Also, a low insulation resistance result does not mean that he had difficulties obtaining the result, it means he tested it and that was the result he got. A result of 1MΩ or greater is acceptable, and a result of below 1MΩ means that circuit requires attention.

It would appear the electrician who did my recent inspection has not done this test on the heating circuit - he has left all readings blank on the heating circuit and stated on the test sheet "unable to test due to timers in the circuit".

On the 2008 report, the results the electrician got on the heating circuit were 0.07, 0.08 and 0.07 for phase/neutral, phase/earth and neutral/earth respectively (for insulation resistance). R1+R2 was 0.25. Zs figure was 0.47.

As these figures appear to be below 1MΩ, what "attention" would this circuit would require in your opinion?

With regards your second point (the Zs readings) as Richard has said the original electrician may have just calculated this from looking at the Ze result and adding it to the R1+R2 result (so it could be obtained with the power to the heating circuit off). You could perhaps look at these 2 results (Ze and (R1+R2)) and if added together equal 'exactly' the result he has put for Zs then he 'may' have just calculated the Zs (unless coincidentally that was the measured Zs, but unlikely). Ze may be written as 'Zs at DB' on the report that you have.

So, with the power to the heating off your electrician would not be able to carry an actual 'measurement' of the Zs, but he could carry out an R1+R2 of this circuit and add it to the Ze (to obtain a calculated Zs).

Again, as Richard has said not all electricians will carry out a R1+R2 on a report if they get a satisfactory Zs so i dont think your electrician should be penalised for this, but an R1+R2 on the heating circuit would have been necessary as no Zs was obtained.

I can't find the Ze figure on either report, either shown as Ze or "Zs at DB". Does Ze relate to the total of the insulation resistance readings?

If so, that might work for the heating circuit - as per my point above, on the 2008 report I have readings of 0.25 (R1+R2) plus 0.07+0.08+0.07 (sum of insulation resistance readings) = 0.47 - which matches to the Zs reading on the report.

However, this calculation doesn't seem to work for the off-peak immersion circuit reading on the 2008 report - this has 0.11 R1+R2, then >500 on all 3 insulation readings. Zs total on this circuit per the 2008 report is 0.30.

It would be interesting to know how long the electrician was there for and how much he charged?

He charged me £90 (no VAT as not registered). Based on his hourly rate for other non-electrical work, that would appear to be 2 hours he spent doing the testing and completing the report/testing details on the summary sheets he gave me. This seems cheap (like the budgie) in comparison with what I spent on the 2008 report and the other quote I had for the work recently.

 

[Soup]

UPDATE TO THE ABOVE POST:

I've found the Ze readings on the reports!

2015 report (current report) = 0.04Ω

2008 report (old report) = 0.23Ω

So... looking at the 2008 report.... 0.25 R1+R2 +0.23 Ze = 0.48 (calculated Zs). Zs per the report = 0.47. So virtually exactly the same, like you guys said. Although that might still indicate the 2008 electrician managed to get a "normal" Zs reading of some sort as the Zs figures aren't identical.

So, I think I will go back and ask the current electrician if there was a reason why he didn't use the alternative calculated Zs (ie do an R1+R2 reading) in the absence of a standard Zs reading.

Is there any issue with the differences between the two Ze readings? (the 2015 Ze reading seems quite low comparatively with the 2008 Ze reading)

This does also still leave the question about the low readings on the heating circuit insulation resistance (less than 1MΩ) so I'd be grateful if you would let me know "attention" this circuit might need, in your opinion?

Thanks guys, your help is much appreciated.

 

[Leesparkykent]

UPDATE TO THE ABOVE POST:

I've found the Ze readings on the reports!

2015 report (current report) = 0.04Ω

2008 report (old report) = 0.23Ω

So... looking at the 2008 report.... 0.25 R1+R2 +0.23 Ze = 0.48 (calculated Zs). Zs per the report = 0.47. So virtually exactly the same, like you guys said. Although that might still indicate the 2008 electrician managed to get a "normal" Zs reading of some sort as the Zs figures aren't identical.

So, I think I will go back and ask the current electrician if there was a reason why he didn't use the alternative calculated Zs (ie do an R1+R2 reading) in the absence of a standard Zs reading.

Is there any issue with the differences between the two Ze readings? (the 2015 Ze reading seems quite low comparatively with the 2008 Ze reading)

This does also still leave the question about the low readings on the heating circuit insulation resistance (less than 1MΩ) so I'd be grateful if you would let me know "attention" this circuit might need, in your opinion?

Thanks guys, your help is much appreciated.

I think you are giving this spark a hard time lol.

 

[Soup]

I think you are giving this spark a hard time lol.

Haha :90:

Hope I don't have this much difficulty when the PAT Tester does his thing in a couple of days ;o)

 

[Leesparkykent]

Haha :90:

Hope I don't have this much difficulty when the PAT Tester does his thing in a couple of days ;o)

Not the same electrician isit? Haha :crazy:

 

[newtothis]

Thanks Lee, just saw central heating. That said, this productt will have its own product standard to which it needs to de designed, installed, commisioned and tested.
Cheers

LOL I'm new to this - first thing I did was google the system the OP kindly provided at the outset.
The electrical installation cert for this system would be handy.
I've been taught as a tester you'd refer to previous test results as a way of monitoring changes, eg like deteriorating IR results. ETC
Seems like the OP didn't provide this info to the spark but has produced it after the inspection to question the current inspection.
Just giving my opinion, don't mean any harm to anyone.
I'm grateful to the OP cos a few years down the line when I'm competent to carry out EICRs I will hang up the phone if anyone mentions this system. LOL

 

[HappyHippyDad]

UPDATE TO THE ABOVE POST:

I've found the Ze readings on the reports!

2015 report (current report) = 0.04Ω

2008 report (old report) = 0.23Ω

So... looking at the 2008 report.... 0.25 R1+R2 +0.23 Ze = 0.48 (calculated Zs). Zs per the report = 0.47. So virtually exactly the same, like you guys said. Although that might still indicate the 2008 electrician managed to get a "normal" Zs reading of some sort as the Zs figures aren't identical.

So, I think I will go back and ask the current electrician if there was a reason why he didn't use the alternative calculated Zs (ie do an R1+R2 reading) in the absence of a standard Zs reading.

Is there any issue with the differences between the two Ze readings? (the 2015 Ze reading seems quite low comparatively with the 2008 Ze reading)

This does also still leave the question about the low readings on the heating circuit insulation resistance (less than 1MΩ) so I'd be grateful if you would let me know "attention" this circuit might need, in your opinion?

Thanks guys, your help is much appreciated.

With regards the Ze reading differences, that is quite a difference! I have only been in business for 3 years but have not come across a Ze of 0.04Ω before, it would be interesting to know if the more experienced electricians on the site have? Even if they have then that doesn't account for the difference. Unless your area has had some electrical work done locally I may be inclined to think he has measured the Ze without disconnecting the main bonding (It would be silly to go into detail about what this actually means Soup, but you could ask him if he did).

Also, those Insulation resistance readings are far too low and you should definitely have an electrician back to check them as if they are correct then there is a fault on the circuit somewhere. I dont want to go into detail about what they mean as it just gets too confusing, also it is very difficult to say more withour being there. Your most recent electrician should have looked at this previous report.

I feel 2 hours is nowhere near enough time to do a proper electrical report on a house, unless your home is a one bedroom flat then perhaps you could justify it if it just has perhaps 3 circuit breakers in the consumer unit (fuse box). Also 2 hours could be justified if before hand you had agreed on a very specific report that was only checking certain things, but in general a report takes at least half a day (4 hours) for a 3 bed semi (I take 3/4 day for a 3 bed semi and charge £150).

I think you are giving this spark a hard time lol.

Thats what I have been thinking Lee up until Soups above 2 posts, but 2 hours to complete a full report? How long do you take Lee and be honest?

 

[Leesparkykent]

With regards the Ze reading differences, that is quite a difference! I have only been in business for 3 years but have not come across a Ze of 0.04Ω before, it would be interesting to know if the more experienced electricians on the site have? Even if they have then that doesn't account for the difference. Unless your area has had some electrical work done locally I may be inclined to think he has measured the Ze without disconnecting the main bonding (It would be silly to go into detail about what this actually means Soup, but you could ask him if he did).

Also, those Insulation resistance readings are far too low and you should definitely have an electrician back to check them as if they are correct then there is a fault on the circuit somewhere. I dont want to go into detail about what they mean as it just gets too confusing, also it is very difficult to say more withour being there. Your most recent electrician should have looked at this previous report.

I feel 2 hours is nowhere near enough time to do a proper electrical report on a house, unless your home is a one bedroom flat then perhaps you could justify it if it just has perhaps 3 circuit breakers in the consumer unit (fuse box). Also 2 hours could be justified if before hand you had agreed on a very specific report that was only checking certain things, but in general a report takes at least half a day (4 hours) for a 3 bed semi (I take 3/4 day for a 3 bed semi and charge £150).



Thats what I have been thinking Lee up until Soups above 2 posts, but 2 hours to complete a full report? How long do you take Lee and be honest?

I price it at 1/2-40 mins a circuit depending on a quick visual. TBH I hate doing EICRs....but if I do them they are done properly but most of the landlords round my way go for the cheapest quote which isn't me.

 

[Soup]

LOL I'm new to this - first thing I did was google the system the OP kindly provided at the outset.
The electrical installation cert for this system would be handy.
I've been taught as a tester you'd refer to previous test results as a way of monitoring changes, eg like deteriorating IR results. ETC
Seems like the OP didn't provide this info to the spark but has produced it after the inspection to question the current inspection.
Just giving my opinion, don't mean any harm to anyone.
I'm grateful to the OP cos a few years down the line when I'm competent to carry out EICRs I will hang up the phone if anyone mentions this system. LOL

Thanks for this. I've tried to get details of the system already from the management company, freeholder/freeholder's agent and the maker of the system but to no avail.

Being honest here, it completely slipped my mind that I had the 2008 inspection done until I got into the argument with the electrician about the 2015 inspection - it was fortuitous that I managed to find a copy of the report after such a long period of time! So I didn't mean to try and catch him out or anything.

With regards the Ze reading differences, that is quite a difference! I have only been in business for 3 years but have not come across a Ze of 0.04Ω before, it would be interesting to know if the more experienced electricians on the site have? Even if they have then that doesn't account for the difference. Unless your area has had some electrical work done locally I may be inclined to think he has measured the Ze without disconnecting the main bonding (It would be silly to go into detail about what this actually means Soup, but you could ask him if he did).

OK I'll ask him that and see what he says!

Also, those Insulation resistance readings are far too low and you should definitely have an electrician back to check them as if they are correct then there is a fault on the circuit somewhere. I dont want to go into detail about what they mean as it just gets too confusing, also it is very difficult to say more withour being there. Your most recent electrician should have looked at this previous report.

As noted above, he didn't have sight of this old report but that's only because he wasn't aware of it (and I wasn't reminded of it until after the inspection).

I'll ask him again about the insulation resistance although I think it'll annoy him and he'll just refer back to the fact there was no power in the circuit and/or there are pin timers in the circuit, preventing a proper test!

I feel 2 hours is nowhere near enough time to do a proper electrical report on a house, unless your home is a one bedroom flat then perhaps you could justify it if it just has perhaps 3 circuit breakers in the consumer unit (fuse box). Also 2 hours could be justified if before hand you had agreed on a very specific report that was only checking certain things, but in general a report takes at least half a day (4 hours) for a 3 bed semi (I take 3/4 day for a 3 bed semi and charge £150).

To be fair, the 2 hours was just an estimate based on his hourly rate for other non-electrical work (£45/hour) so just a guess on my part. My property is a 2-bed flat so maybe that would be OK in terms of time spent in this instance. The fact he didn't measure certain things like R1+R2/R2 etc might be where he "saved time". Nice to know my continual questions don't seem to be so over the top now though :shades_smile:

 

[newtothis]

[FONT=&quot]Wishing every success with your venture Soup – there seems to be endless red-tape with absolutely everything these days. [/FONT]

 

[YoungScud]

I'll ask him again about the insulation resistance although I think it'll annoy him and he'll just refer back to the fact there was no power in the circuit and/or there are pin timers in the circuit, preventing a proper test!

Sorry to leap in late, but I've read this whole thread and I'm puzzled about something. Why would a lack of power affect insulation resistance tests? They have to be done with the power off. Zs testing can be done by measurement or calculation, meaning that, if you do a measured Ze test, you can calculate by adding R1 and R2, or you can measure Zs wit the power on. However IR testing is definitively a dead test.

 

[DuaneMHunt1976]

Would doing a Ze test with all the EARTHS in give you a real Dam Low 0.04Ohms value, apose to the 0.23 Ohms the last time

As YoungScud (so wanted to type in YoungStud then) said IR is a DEAD test, so No power Great, Zs a Live Test other wise its the R1+R2+Ze=Zs with no Power would be yes.

 

[davesparks]

Would doing a Ze test with all the EARTHS in give you a real Dam Low 0.04Ohms value, apose to the 0.23 Ohms the last time

That would be a Zs test, if done at a DB it's commonly called Zdb

 

[YoungScud]

Would doing a Ze test with all the EARTHS in give you a real Dam Low 0.04Ohms value, apose to the 0.23 Ohms the last time

As YoungScud (so wanted to type in YoungStud then) said IR is a DEAD test, so No power Great, Zs a Live Test other wise its the R1+R2+Ze=Zs with no Power would be yes.

Leaving the parallel paths in circuit might or might not significantly affect the reading (the more parallel paths, the more likely the difference will be large). It's the whole reason that Ze measurements should be done with the customer's bonding conductors disconnected, and consequently the installation switched off.

By the way, YoundStud is Ok with me. That gives me an idea...

 

[DuaneMHunt1976]

It was more of me suggesting that they really do a Zs/Zdb reading and why the 0.04ohms for Ze

With more points to Earth the resistance will drop (ie parallel Resisters)

 

[Soup]

Right then gents, got another response in this continuing saga.

Regarding his inability to read the Zs on the heating circuit and the off-peak immersion, I asked the following question:

"regarding the Zs reading, it seems you can "calculate" the Zs using the R1+R2 and Ze readings as an alternative in certain circumstances (eg if the power is off, like in our case). Maybe that's how the previous electrician calculated the Zs for both the off-peak immersion circuit and the heating circuit on the 2008 report? (although I note the 2008 figures don't quite match using this calculation, they are very close)."

His response :

"Yes, indeed it can be done this way, but then you have to measure the values of r1 and r2 which as I mentioned before, this continuity testing was not done in this case as you have to actually have continuity without switches or timers in the way. I can’t comment on how the 2008 test was done."

My 2nd question was:

"Just out of interest, having now had sight of the 2008 periodic inspection report, is there anything you noticed from the comparative figures that you think I should be aware of? ie are there any notable differences in the figures between the two tests that points towards degradation of any sort, potential problems now or in the future etc- eg Ze figure of 0.04Ω in 2015 vs 0.23Ω in 2008; also, cooker Zs jumped from 0.23 in 2008 to 1.2 in 2015, the latter figure being above the maximum permitted Zs figure of 0.85 noted on the 2008 report."

His reply was :

"This is getting a bit vague as it was a while ago now, but this value was probably obtained from the socket on the side of the cooker switch rather than the cooker circuit on its own, hence the higher value reading."

So... any thoughts on his comments on either of these? Does the point about switches/timers affecting continuity make sense?

He hasn't really answered the Ze point on my 2nd question, nor has he commented whether the Zs value on the cooker is overly high/outside of the maximum permitted figure of 0.85 per the 2008 report either (NB the cooker is "hard-wired" rather than having a 3-pin plug).

 

[Leesparkykent]

Are you withholding payment on this poor bloke or something?

 

[Richard Burns]

Overall you have had an EICR done on the property, you have been supplied with the appropriate paperwork.
The electrician has failed to cover one aspect of the inspection, which you had specifically asked about, and his response about this was that it was outside his expertise to do this.
You are then querying further aspects of his work (which are somewhat odd but likely he was pushed for time and could not cover all the additional slow testing) and have now produced a report that could have saved him a significant amount of time and you some money and are now querying the comparisons which he had no opportunity to make.

I do not think you are going to be successful in getting any further work from this electrician as it will seem as if there is nothing he can say that will bring this to a close.

 

[Soup]

Overall you have had an EICR done on the property, you have been supplied with the appropriate paperwork.
The electrician has failed to cover one aspect of the inspection, which you had specifically asked about, and his response about this was that it was outside his expertise to do this.
You are then querying further aspects of his work (which are somewhat odd but likely he was pushed for time and could not cover all the additional slow testing) and have now produced a report that could have saved him a significant amount of time and you some money and are now querying the comparisons which he had no opportunity to make.

I do not think you are going to be successful in getting any further work from this electrician as it will seem as if there is nothing he can say that will bring this to a close.

Thanks for taking the time to reply, but I think you're missing the point here a little.

The previous report - which I was only reminded of after the recent test because I was querying why he hadn't completed testing on certain circuits - was only sent to him to ask him how the previous electrician may have managed to get readings where he couldn't (I know I have since asked him to compare the figures on the report but my reasoning for this is set out below).

At the end of the day, as a landlord I need to be able to say that the internal electrics of the property are safe. The previous report had more detail generally, as well as completed readings for the tests he was unable to complete - and this coupled with the fact that there is further doubt about the reliability of some of his readings/methods (even you say that some aspects of his work are "odd" in your post), makes we wonder whether his report as a whole can actually be relied upon. Hence my questions to the good people of this board, and further questions to the electrician, to try and understand it all a bit more and ascertain whether this is the case - which I'm well within my rights to do.

Put simply, I don't see why I should pay for a job if it has not been done properly (if indeed this is the case here). And to be honest, I'm still unsure what the true situation is! :rolleyes4: And even if I do ultimately get a resolution I'm unsure if I would use this electrician again anyway, given the protracted nature of the post-report discussions I've had with him.

And finally, just an FYI - I am being charged a flat fee for the work, so no extra costs for time spent as far as I am aware.

 

[Richard Burns]

I think you have raised an interesting point with us, you are unhappy to pay for a report that is unreliable, however you have not raised this point with the electrician, you have only kept asking him further questions of a specific nature.
I would suggest that if you are unhappy with the report that you inform the electrician, as you have just done here, of your reasoning and see what comes of that.
We are unable from a distance to be able to specifically state if something is definitively wrong; there are some "odd" items but these may be due to various circumstances that we are unaware of as we only have the information you have given us..

 

[Soup]

I think you have raised an interesting point with us, you are unhappy to pay for a report that is unreliable, however you have not raised this point with the electrician, you have only kept asking him further questions of a specific nature.
I would suggest that if you are unhappy with the report that you inform the electrician, as you have just done here, of your reasoning and see what comes of that.
We are unable from a distance to be able to specifically state if something is definitively wrong; there are some "odd" items but these may be due to various circumstances that we are unaware of as we only have the information you have given us..

I have already told the electrician I was unhappy he didn't/was unable to test certain circuits that I had specifically asked him to ensure were looked at, prior to starting the report.

However, like I said in my previous post, I'm still unsure if the report is unreliable, or if he has actually done anything wrong which warrants me complaining further. There are a lot of "question marks" here, but at the end of the day it wouldn't be right for me to make baseless or ill-informed accusations at him if he's done his job properly. Hence my continued questions on here trying to get to the bottom of it all!

I do understand your point about being unable to specifically state if something is definitively wrong "from a distance", as you put it. I was aware this was unlikely to be a straightforward black and white problem and the responses to date have indicated that. However, IF there was something in the information I had provided that you guys highlighted which was clearly incorrect/wrong then I could query him on it - and this is what I was trying to ascertain in my last set of queries.

Hope that clears it up!

 

[DuaneMHunt1976]

The Ze, I think 0.04 is dam low, you living next door to a sub station.
As for the value can be got by measure or just asking, don't think the board will give a value that meets.thenbs7671 standards for your setup

R1+R2, could I guess link at db (turning off power to this) and doing a.R1+R2 To the accom7 and then link at the accom7 then to the heater
Zs = Ze + (R1 + R2 [Db to accom7]) + (R1 + R2[accom7 to heater])

This may get edit because saying some thing shouldn't do, but R1 is about the same value as Rn and the circuit works, so I know R1 is good
So would doing Zs = Ze + Rn + R2 be about the same as Zs = Ze + R1 + R2
It will prove continuity for R2 and Rn, and we know R1 works as the heater works
Insulation Resistance test too