Split unit sensor explanation fault diagnosis?

[karl957]

Hello can any one shed light on what symptoms are normally found when any of the sensors fail on the indoor and the outdoor air conditioner. How to fault find and where to look when unit does not operate correctly? I am new to airconditioner repairs and am looking for all technical advice and any training information or material as I have only previously been doing domestic fridges.Thanks guys I know that I will always get the bestadvice from the great techies and engineers here.

[Grizzly]

Welcome Karl.
The problem with your question is that it has to many possible answers.
Simply put on most of the split systems i know.
There are fault codes that are displayed whenever there is a fault.
Totally logical, where it gets grey is that the fault displayed.
May or may not indicate that it is a direct result of a sensor fault.
Meaning that there are many faults that could be as a result of a faulty sensor.
But the vast majority would normally have you looking elsewhere prior to eventually discovering that a sensor has malfunctioned.
In all fairness it really depends on what sensor and what system.
My advise is download the service manuals and other literature, relevant to the equipment you work on.
If necessary use the forum search button.
You will Find lots of good and helpful advise.
Sorry I can't be more specific but as I say the topic is to big!
Cheers Grizzly

[karl957]

Thanks Grizzly I am at the moment just fishing for advice and information, till the picture becomes clear. To repair anything it is best to fully understand the controlls and operation, I found that getting into something takes alot of system and operational knowledge and then still no one knows everything, you still will get faults that trouble your sleep at night. Error codes can also lead you astray, I worked in a workshop and always enjoyed the challenge of the complicated and challenging jobs that really made you think. So until I understand the air conditioning system I will be asking a lot of questions. The refrigerant side is no problem for me I fully understand the cycle. Technical service books today hide a lot of important knowledge and information because engineers in factorys think that you do not need to now certain things, instead of them giving you the information and let you decide what you can use they just omit to include it in the service manuals. If any one can send me any literature that might help I will be eternally greatfull. I will be working on domestic (home) airconditioners. Thanks for your feed back and good advice recieved so far. Have a great day, Karl

[superswill]

karl,

searching manufactures websites for relevant downloads is key here,find what systems you will come into contact with and download the relevant PDF,

http://www.toshiba-aircon.co.uk/tech...ech_02-02d.htm

http://www.dolphin-airco.be/documentatie.html

http://www.heronridge.co.uk/tech_info.htm

above are a few to start you off

[karl957]

Thanks Paul I will download a few manuals from the sites that you have mentioned and that will be sure to help. If you have any other good information Please send a PM so that I can share my email address. Thanks for sharing.

[Grizzly]

Superswill thanks for the good links.
Grizzly

[paul_h]

Who do you work for Karl?
I'm just asking because most people who repair splits in australia normally work as a service agent that specializes in split system repair of a few brands and has all the factory manuals, tech advice etc.
I learnt my info by working for authorised service agents for a few brands.
With manuals and experience I learnt the common faults and symptoms which I could apply to other brands, although I do need to come here to ask about the brands I don't have experience on like daikin.

I'm just asking because you seem to be thrown in the deep end without any support, and it's unsual for many companies here to even attempt split system repair if they don't have the manuals or tech help. Normally if companies don't have all the knowledge to repair, those companies just recommend replacement to customers instead of making employees like you lose sleep

Don't forget, it's an easy sell to replace a unit, especially a wall split. They come with a 5 yr waranty here, so if you aren't working for a waranty service agent, it's at least 5 yrs old. Not to mention that compressor and inverter PCBs are a rip off for spare part prices, easier to sell a new unit with another 5 yr warranty for $2k than a repair with a 3 month warranty for $1k.

You can always ask here and I'll help if I can along with everyone else I hope. But just pointing out that what seems to be expected of you is not normal here as far as level of competence in repairing splits.

Example: major installer of pana/daikin here gets the maintenance of the splits. I've picked up a lot of work because the techs from this company quite often get diagnosis wrong, ie condemn compresor when only the soft starter or PCB is faulty. That's like $1K+ extra of faulty diagnosis.

example2: You were asking about the samsung inverter board/compressor fault before. Standard here in australia, is if you are not sure, replace both compressor and inverter. If the price is almost the same as a new unit, refer to my ealier point, quote to replace the unit
(not that I agree, but it is the standard - that's why I started my own business, to offer better service )

example3: A guy had a basic conventional compressor mitsi split that had a indoor LED flashing, 3 different companies told him to buy a new split and quoted install. They all said his compressor had burnt out because it was pumping too hard after all these years as he had a 5m vertical pipe run. The unit's are rated to 5m verticals just fine.. Those basic units only register faults for fan lock or thermistor faults. So because of a simple thermistor fault (fan was still blowing air), they tried to tell him the compressor was burnt out and he needed a new unit.

example4: Today someone told me their ducted evaporative cooler wasn't cooling, just blowing hot air. They had a quote from an a/c company for $1400 to repair. Apparently the whole thing needed to be stripped down and all sorts replaced.
I spent all of 20min plugging in a new water pump and walked away with it working perfectly fine and $200 richer. Maybe I don't charge enough and that's why I'm not rich. But being an evap cooler the thing will break down next year etc and I'll get repeat business from them and hopefully friends/family and workplaces. All I know is $200 is good for 20min work.

So if you want any help, just ask. If you want to really learn this stuff, work for an authorized service centre for as many brands as you want. But if you are happy where you are and you are only an employee, you shouldn't have to search for all this info yourself, and you don't need to just to be equal with the average australian a/c mechanic, hardly any of them know any more than basic fault code from a chart and they just order as many parts as it takes to cover their own arse.

edit: short version: Don't feel presured to know all this stuff for your job, feel free to ask questions to learn for your own benefit though, or change jobs to a service agent where they will give you this info and teach you.
PM your mailing adress and I will send you everything I have, I've got about 4gb so it will fit on a DVD but takes too long to up/download.

[karl957]

Thank you Grizzly for all your assistance and help you make this forum rock.

[karl957]

Thank you Paul h for your help, I think that your advice is apt, its just when you are new in a country & company you like to do your best and learn as much as possible as quickly as possible. Thank you once again for your help.