Meggering/insulation testing combis

[LaMont5way]

Hi. I was wondering if any domestic gas service engineers out there megger/insulation test whilst diagnosing boilers or for electrical safety purposes. I have heard before it could damage the appliance but, a domestic boiler is no more sensitive than any other domestic electrical appliance e.g refrigeration, laundry. Any information would be greatly appreciated.

P.s I have already posted this and was told to register to receive advice, I have now done this. And to the person who asked if I would 'megger' a television and at what test voltage; mono 240v 50hz supply to appliance,so for the test you would double this to 500v. I didn't quite understand your question, but, were you suggesting I use a tester with a special I.T test function for boilers because they are like televisions,as opposed to the likes of the Fluke 1577? Cheers.

 

[kris]

Hi there LaMont5way and thanks for taking the time register, no we dont use meggers while diagnosing boilers , I have an analogue megger that goes up to 1000v jolt but i only use it when testing water heater element prongs for breaks or cracks etc, when im working on boilers i use my fluke 116 multifunction tester and my fluke T150 , although the 116 does all that needed ,

 

[Dotty]

Multimeter only. Boilers are voltage sensitive

 

[IDCHAPPY]

I'm a monkey, not a spark, if it gets 240v and doesn't move it's funked

 

[joni os]

Is that a technical term or a tipo.

 

[gasmanrob]

Stick a megger across a duotec board and you'll be dipping your digits in your pocket for a new one.

 

[LaMont5way]

Thanks for clearing that up. You would of thought a healthy transformer would be able to cope, but I know from experience in the event of any kind of surge in the supply modern boilers don't fair well. I still think this testing could prove beneficial for diagnosing certain faults like intermittent loom faults due to wiring shorts or even pumps ,fans. As long as you could test circuits/components separately from the pcb/pcb's, right? And thanks again guys.

 

[kris]

Thanks for clearing that up. You would of thought a healthy transformer would be able to cope, but I know from experience in the event of any kind of surge in the supply modern boilers don't fair well. I still think this testing could prove beneficial for diagnosing certain faults like intermittent loom faults due to wiring shorts or even pumps ,fans. As long as you could test circuits/components separately from the pcb/pcb's, right? And thanks again guys.

I know looms can go from time to time but mostly in my experience its a functioning part that goes and modern boilers now are easy enough to test the looms continuity with a multimeter, for easyness I do like my fluke t150

 

[gasmanrob]

If you could disconnect the board and components then as far as a theory goes it's a grand idea, however the reality of having a kit to suit every manufacturers wiring looms would cost the same as the tester itself thus making it un viable.

Perhaps a hvac specific unit with variable outputs, where you were able to split wiring looms and test 2 leads at a time might prove more practical but quite labour intensive, plus the added ache of getting into the pcb housing on something like a eurocombi or even a chaffataux, it's unlikely to take off or warrant the cost

 

[Dotty]

I know looms can go from time to time but mostly in my experience its a functioning part that goes and modern boilers now are easy enough to test the looms continuity with a multimeter, for easyness I do like my fluke t150

Nice bit of kit that. I just got one.

 

[kris]

Nice bit of kit that. I just got one.

Yeh john I got sick always needing 3 hands with the multimeter lol, it's great with the digital display aswell,

 

[LaMont5way]

I like the look of the tester looks very convenient, thanks. But can you renew test leads or is it buy new meter? It's the only thing that has put me of these meters. Looks an awesome piece of kit though!

 

[quality]

I have used a megger on ignition and detection probes but only a handfull of times and only because i have one

 

[kris]

I like the look of the tester looks very convenient, thanks. But can you renew test leads or is it buy new meter? It's the only thing that has put me of these meters. Looks an awesome piece of kit though!

Can't renew the leads but you can get attachments or extension pieces to go on the end if required,

 

[newcastle phill]

Theres no technical reason why you cant megger a boiler from the LNE wires.
Like any other class 1 2 or 3 appliance they are designed to deal with certain electrical conditions.

My megger will also do a 240v IR test and there is no way that will damage a boiler as thats the same as the mains feed.

The real question is what do you hope to gain. Id be more inclined to test individual components such as fan or solenoid valves out of curcuit.

With current boilers and any other appliance with a pcb you will more than likely only be testing as far as the on off switch upto pcb inputs. As unless the board is properly energised through things like relays pulled in etc - the megger wont 'see' them.

So to summarise 240v wont do any harm

 

[lame plumber]

unless you inadvertently stick 240 through a low voltage circuit

 

[newcastle phill]

You cant do that from the lne inputs

 

[LaMont5way]

Thanks for that Newcastle phill , reassured my own findings. As we all know the tool is practically unheard of in the industry, manufactures make no mention neither do any company's. I still think it could pick up certain faults regular testing can't, although maybe a good engineers intuition may render such testing too timely,possibly damaging , and generally pointless.

 

[newcastle phill]

I agree, with my background before gas being heavily electrical /electronics based testing and repairs. I love my megger, can detect easily a whole multitude of faults that a voltmeter cannot.

 

[drip-dry]

Anyone who thinks they can get stuck into a combi or any electronic appliance. With a volt stick is slightly suffering from ..of course I know what I am doing..

 

[AWheating]

why would you want to insualtion test a boiler?