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Re: Questions from a 4th year Apprentice
I might buy one for the house anyway just to play around with and help get my head around some electrical theory.
I guess he got into this business after an unsuccessful career in communications?
Haha you are actually right.
Any further questions you have do feel free to fire away as we’d love to help you further. 😀
Thank you very much! That really does mean a lot. I’ve finally gotten a good grasp on some basic electrical theory since joining this forum and – i will keep learning. I don’t want to overburden myself with information that i end up never needing (as i have a tendency to do. I started off reading electrical theory …ended up reading about space.) So how important is it I’m able to follow and understand electrical diagrams? I feel this is something i should know but I’ve never had to use it.
Thanks again for your willingness to help I’ll be sure to post questions as they come up :snig:
Re: Questions from a 4th year Apprentice
Sorry, i mean to say that if an appliance has already been PAT tested (most have as per the sticker attached to the front), my boss will take that as an indication that it is safe. Unless, of course, the fault we are there to see is (or we spot something obvious) dangerous and in need of repair/replacement.
I can’t just buy and start using an insualtion tester though. I will be shown the door lol
So it really comes down to wether the companies practices sit well with me or not. I really don’t want to leave but don’t want to be ‘on the wrong side’ either.
Re: Questions from a 4th year Apprentice
My boss would probably just tell me ”that’s what PAT tests are for, it’s already been done.” I definitely wouldn’t be allowed to buy a megger never mind actively use one because “that’s not how we’ve been trained”.
This is an awkward situation. I want to do thing’s right and want to keep learning too. But I do not want to leave this job.
Re: Questions from a 4th year Apprentice
Look, I have already asked a lot of questions here and am really gratefull for all the advice. If I’ve outstayed my welcome please let me know.
I spoke to my boss and I was told that everything I need is on my multimeter and also that we don’t do PAT testing anymore. Apparantly, as long as I can open an appliance and follow and understand the wiring, how the wiring and mechanics work and relate, and test for live and neutral – then I’m okay. There are some circumstances where we would test for reaistance but they are few and far between. I’m not sure if that is good enough? But to be fair, for most of the work we do in this high pressure fast paced environment – our diagnoses are rarely wrong.
I like getting the opinions of you guys here and always think up more questions regulalry. That is, if I’m not being too pestlike at this end of ‘the trade’ 😛
Re: Questions from a 4th year Apprentice
Sorry, i don’t follow. Side by sides? We don’t do any refrigeration warranty work.
Re: Questions from a 4th year Apprentice
Great info! Having read through everything twice , I do still have some questions though if that’s okay?
NOTE: I have not been taught much about fridge freezers simply as it is something we don’t really do. It is hard for us to get the parts for American style ones so we just don’t look at them and almost any fridge freezer with a digital board seems like more hassle than they are worth in terms of spending both time and money on them. We don’t re-gas either. We replace the odd traditional thermostat but not much else.
Therefore, i have not come across a lot of fridge freezers. However, i dislike feeling like I’m looking at an alien object when i do come across one and would like to know more of their inner workings!
1. The “thermostatically controlled air flap to control the airflow into the fridge” …how common are these for failing? I have never even heard of these!
And are these pretty specific to American style fridge freezers?2. Do most frost free fridge freezer have a defrost heater? Or, again, is this pretty specific to the American style?
3. Are defrost timers even inside modern fridge freezers? Or built-in to the PCB? I’ve never heard of these either :/
4. In regards to non-frost free fridge freezers, if they do not have a fan blowing up cold air from the freezer to the fridge, then what regulates the temperature of the fridge? Are there 2 different compressors and thermostats?
Re: Questions from a 4th year Apprentice
My boss is an animated, frustrated person who goes off on long winded tangents. And has always been this way. With, like, everything in life. So most of the time you ask a question you get an animated, frustrated, long winded answer. But the fault also lies with me. I make the same mistakes over and over, and I find it hard to focus. For someone who has never, ever, had a previous interest in engineering – I find it hard for my brain to adjust to the purely logical way of thinking. I’m sure that must be frustrating.
We are on good terms. Don’t get me wrong with any of this topic. It’s just there are some things I never got a simple straight answer for. And for someone 4 years down the line, I find this unacceptable imo. It would be easier for me at this stage to seek a little clarification elsewhere rather than get my head bitten off/be made to feel stupid.
So, with that said :rotfl: :
1. I get confused with frost free and normal fridge freezers here. I understand that with frost free there is a fan in the freezer that simply blows the cold air up from the freezer to the fridge via duct behind the plastic moulding at the back. If this gets blocked with ice then a thorough defrost is needed. However, on a normal unit, what would stop the fridge from cooling efficiently? The same principle? Just the insulation being blocked with ice?
3. When you say electronics also suspect, do you mean if there is a digital board/thermostat?
I also get confused how to tell wether a compressor is not running due to a faulty thermostat, or an actual compressor problem? Is there any hints, tips or tricks to tell the difference?
Thanks again!
Re: Questions from a 4th year Apprentice
Okay! Fridge freezers!
Is there an easy way to diagnose fridge freezer problems? For example:
(Assuming the obvious that the appliance doors are sealing correctly, is loaded correctly inside, is not too hot/cold in the room itself etc. We are talking about actual faults with fridge freezer units specifically)
1. Freezer compartment ok but fridge compartment too warm – in need of thorough defrost, if problem persists then shortage/chokage of gas.2. Compressor running. Both fridge and freezer compartments too warm – shortage/chokage of gas.
3. Compressor not running. Both fridge and freezer compartments too warm – thermostat or compressor problem.
That should be enough just now to get some discussion going…
Re: Questions from a 4th year Apprentice
Aw man now I’m really confused lol! I guess i should be content with what Dave says; it’s a bit of a non argument and I’m better concentrating on learning how to fault find and fix things rather than random questions. That is basically what my boss has said before too. I just hate not knowing things, you know?
Is there any really good electrical theory books you guys would recommend?
An insulation tester? Unless there is a setting on my multimeter to test for low insulation – then no.
Re: Questions from a 4th year Apprentice
Ah right, using a multimeter? I need to get more proficient at that.
Not really, all basic explanations say that live goes in and neutral goes out. I just want ti know what my boss means by neutral carrying current in (to a load).
Re: Questions from a 4th year Apprentice
Hi guys,
I have been away the past couple of weeks so sorry for the lack of response.
So, just to summarise; it seems that my original assumptions were correct? The reason online tutorials weren’t telling me about neutral wires carrying current into a load (as my boss had explained) is because they were explaining the basic function of neutral in a circuit rather than the details of neutral in an AC circuit specifically? Is that correct?
Dave are you referring to a continuity test? Also, i had no idea about the discovery that electrons flow the other way. That is very interesting!
Re: Questions from a 4th year Apprentice
Thanks very much for your help guys!!! It means a lot. Really.
My boss means well there is just little room for patience.
In both AC and DC circuits the wires transmit the current created by the load (the load in this example being a heating element). The live wire is ‘the supply feed’ the neutral ‘the return’.
This was what i originally assumed. But I’m not sure i fully understand this in regards to AC, Martin. If the current is constantly changing direction then how can it go into the load via the live wire (supply) and then out via the neutral (return)?
Or is it as Dave says where
current in an AC circuit changes direction, so both wires carry the current to the load
?
This makes more sense to me as it shows that both wires carry the current to the load although the voltage is in the live as the neutral voltage is relevant to ground.
Make sense?
Re: Questions from a 4th year Apprentice
Thanks very much for your responses guys.
I am sure your boss wont say no to that
Haha unfortunately no, Dave. I can imagine my bosses reaction to that.
May we ask what your current job entails exactly?
We repair domestic appliances i.e. washing machines, ovens, dishwashers etc. There are a lot of good looking books out there Martin – to the point I’m not sure which to pick. As i should be learning enough from my teacher, i thought it might be best just to ask a few basic questions on a likeminded forum rather than diving into more books (I have read a lot of Haynes manuals for various appliances).
I’ll post here and see what happens as Dave advised.
All i basically want to know is how the neutral wires works exactly in appliance circuitry.For example, before i started my apprenticeship, i always thought that on any and every circuit the live wire has current going into the load and the purpose of the nuetral wire was to curry current away and back to source. So without a neutral wire a closed circuit was not possible and a heater element, for example, could not operate.
That’s how i thought it worked. But when i relayed this to my boss i was made to feel very stupid. I was told that both a live wire and a neutral wire will carry current into a component. I read up on it but could not find anything anywhere which confirmed exactly what my boss said. Everything explained neutral the same as the example i gave above.
It actually was quite a while later before in realised that my idea of how nuetral worked was relevant to DC electricity. How my boss explained the way neutral worked in appliances was due it being AC. Is this correct? (I’m very serious when i say this was never explained to me).
So, as i understand it – both the live and neutral wires carry current into the component (heater element). As it is AC the current is oscillating back and forth slightly at a really fast rate. This is how current flows in an AC circuit and how the appliance is powered. The live wire carries the voltage whereas the neutral carries very little.
Is this correct?
