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SirGr3mlin
02-02-2020, 08:51 AM
Hi all, first post sorry if its in the wrong place.
Quick background, i no very little about the air conditioner layout, everything i know is just from inspecting and guessing really. (so if anything below isnt correctly termed. please dont kill me) im a noob! ;-)
Details :
I was given an air-conditioner recently (delonghi pac w160a) we use to use it in the old office but it wasn't keeping up with the increased temps in the room so they had another installed.
basically it has sat there for 2 years and they said take it.
I got it home and checked it over, what i discovered is that the compressor is turning on and humming away, the pipe going from the compressor to the Condenser is getting hot and the pipe going up to the Evaporator i can see frost forming on the pipe but the evaporator itself isnt getting cold at all.
after sometime the compressor turned off and on inspecting i found it was rather hot. like ouch that is hot, too hot to touch "hot". so i'm sort of thinking its over heating and if it has an internal shutoff then it triggered.
Now, as i mentioned im not an expert but, im sort of thinking is it possible for the gas to have done its dash/gone bad? (if thats a thing) im not sure how many years it has been running for. but i know it was used for at least 2 while i was at that office.
I did initially suspect a leak but i didnt think that there would be any condensation on the evaporator pipe if there was no gas in it?
i checked all the things i could including the cap for the compressor which is giving around 24.25uf (25us 5% rated)
there were a couple of other caps but they seem to run the fans so didn't test them.
I checked the resistance between the compressor terminals as well in case that might help.
(W) - (U) : 4.5 Ohms
(W) - (V) : 6.0 Ohms
(U) - (V) : 10.4 Ohms

Im just wondering, as i love little projects like this and hate throwing things out if i am able to breath new life into them again, if someone has any idea what my fault could be?
If more information is require let me know.

Thanks
SirGr3mlin

frank
02-02-2020, 12:00 PM
When the unit is cool and the compressor is running, does the evaporaor fan run?

martinw58
02-02-2020, 03:04 PM
it sounds like its lost its gas charge

SirGr3mlin
02-02-2020, 08:37 PM
When the unit is cool and the compressor is running, does the evaporaor fan run?
Hey Frank! :-) Yes, both the Evaporator and Condenser fan's run.


it sounds like its lost its gas charge
Heyya Martin! :-( so 50kg paperweight? although its a bit big for the desk. :-(

frank
02-02-2020, 10:03 PM
Frost forming on the liquid line on A/C indicates a shortage of refrigerant

SirGr3mlin
03-02-2020, 12:19 AM
Frost forming on the liquid line on A/C indicates a shortage of refrigerant

thanks frank, so its likely got a leak? and probably isnt worth repairing? there is some rust on the evaporator mounts. not on the copper pipes but near/around them. and actually same with the Condenser. :-/

frank
03-02-2020, 07:41 AM
The only way to determine a SOG is to recover and weigh the charge, but as you are a noobe I doubt that you have the equipment or want to splash out some cash for a fridge tech?

Out of interest, what type of refrigerant is in the unit?

Reading the manual for the unit, it appears that it has a water container - are you running it with the container full, as per the instructions?
https://cdn.productreview.com.au/document/entry-product-manual/075c1081-c0b7-3e28-b9c5-7b0f09893463

SirGr3mlin
04-02-2020, 03:48 AM
The only way to determine a SOG is to recover and weigh the charge, but as you are a noobe I doubt that you have the equipment or want to splash out some cash for a fridge tech?

Out of interest, what type of refrigerant is in the unit?

Reading the manual for the unit, it appears that it has a water container - are you running it with the container full, as per the instructions?
https://cdn.productreview.com.au/document/entry-product-manual/075c1081-c0b7-3e28-b9c5-7b0f09893463

Thanks for the reply, ive rung around the local places prior posting, none of them will work on a portable unit. one said if you bring it in we can have the guys see if we work on them. (but i would need to put all the overs back on. i would happily pay if it was fixable / worth fixing. but i dont want to go spending 500 bucks when a new one is 800. if you get me?
So i just checked the gas and apparently it is "R410A"

Yes, it does have one, i poured 13.5 litres of water into it. looking at how the water is piped it look like it goes down into a tray where another motor literally flicks water onto the Condenser coil/rad thing. I did find the manual and go through, however it looks like the water mode is an optional feature. if no water is added the system 'switches automatically to air-air'

No ive realized something, when i mentioned frost on the copper pipe going into the evaporator coil/rad i was the last 2 cm of pipe going into it. so basically at the coil/rad thing not the entire pipe.
actually i noticed it goes from a smaller say... 3-4mm copper pipe to a bigger 6-8mm just before going into the evaporator coil. the 3-4mm pipe is cool to the touch but not frosting up. just the last 2cm of the 6-8mm pipe.

frank
04-02-2020, 07:20 AM
Have you taken any temperature readings of the air before and after the evaporator to determine that it has poor performance. If you have a touch temp probe you can also measure pipe temps

SirGr3mlin
07-02-2020, 07:57 PM
Thanks for you help Frank, ive decided to put it back together and send it off to be disposed of (after my house inspection so they suggest AC to the landlord ;-) think it is going to require a bit of work to get working. So its probably best i give up this project. :(

intro2010p
08-07-2020, 03:51 PM
The only way to determine a SOG is to recover and weigh the charge, but as you are a noobe I doubt that you have the equipment or want to splash out some cash for a fridge tech?

Out of interest, what type of refrigerant is in the unit?

Reading the manual for the unit, it appears that it has a water container - are you running it with the container full, as per the instructions?

Thanks for sharing your thoughts and a link, it helped for our AC issue as well. We've found and purchased a new model called EdgeStar AP8000W from one well-known camping air conditioner (https://99camping.com/best-camping-air-conditioner/) resource. It really can cool a pretty wide space and digital thermostat feature, and there are no problems with all those tubes, but was that issue, which mentioned above. It seems like it was all about refrigerant, so we've changed it and now it's totally okay.