Why won't my A/C work???

[OliverWestby]

I have a delonghi pinguino '92 portable air con unit, I think it is also known as the PAC 19.
The problem I have is that It won't cool the air blowing through into the room.

From what I can see from removing the covers, there is a compresser which compresses what I think is probably a gas and then pumps it through pipes with water running over them, then through a radiator with air coming out the tube at the back. After tthis, the pipe gets much wider, and off the wider part it a small pipe going to the top radiator to cool the air entering the room.

The Problem seems to be that the overload switch is coming on, and as I don't have the schematic, It is difficult to work out what may be causing this.

Are the any common reasons for this type of problem? and If you have a schematic for one of these units I would be greatful.
Thanks,
Oliver

[Abe]

I have a delonghi pinguino '92 portable air con unit, I think it is also known as the PAC 19.
The problem I have is that It won't cool the air blowing through into the room.

From what I can see from removing the covers, there is a compresser which compresses what I think is probably a gas and then pumps it through pipes with water running over them, then through a radiator with air coming out the tube at the back. After tthis, the pipe gets much wider, and off the wider part it a small pipe going to the top radiator to cool the air entering the room.

The Problem seems to be that the overload switch is coming on, and as I don't have the schematic, It is difficult to work out what may be causing this.

Are the any common reasons for this type of problem? and If you have a schematic for one of these units I would be greatful.
Thanks,
Oliver




The only part which threw me is when you say a radiator with water passing over it.

That might be the condensate pipe.

Anyway, Me thinks that radiator you refer to, with a fan behind it, needs cleaning. Brush it down, remove dust, fluff, debris.... If you have a vacuum cleaner, suck it clean.

Your unit probably tripping on HP switch.

Switch it on again.........Good luck

[Larry2]

Maybe you could post a photo of your unit? Does it ever blow cool air, or is it off on overload right away? How long before overload cuts it off? Do you hear it start the compressor when you turn it on? Describe as much as you can, even if you think it's trivial. Observations are the first step to diagnosis.

[OliverWestby]

I don't have any pictures at the moment, but I'll try to post some.
It does cool the air slightly, and i think the compressor works as it gets rather hot after having the unit running for a while. the switch clicks, then about 5 seconds later clicks with a different sound. this repeats every 30 seconds or so.

Also what do you mean by HP switch?

Oliver

[frank]

SOG ;) :eek:

[Jus Walker]

Does sound like tripping on H.P ( High Pressure ) Becuse the condenser will be clogged with dust. look for dust! clean it by vaccum.

[frank]

Does sound like tripping on H.P ( High Pressure ) Becuse the condenser will be clogged with dust. look for dust! clean it by vaccum.

These little portable units don't have HP protection - just the klixon.

[Brian_UK]

If the unit is a '92 then it is quite likely that the water cooled condenser needs descaling.

The water running over the pipes is there to cool the hot gas from the compressor, after some time the pipes will get scaled up just like the inside of a kettle.

You need to drain the unit, after unplugging it of course, and remove the plastic cover around the water cooling section. Have a look at the pipework, it should be clean copper pipe but probably isn't by now.

You can get heavy duty descaler or you could try a heavy concentration of kettle descaler or similar.

You can sometimes scrape off some of the heavier scale but be careful do not damage the pipework at all.

[OliverWestby]

It does have alot of scale on it so I will have a go at taking that off. It does seem to only trip while the water pump is running (only on when in "super cool" mode)
Should I runthe unit descaler in it to remove the lime scale from the pump as well.

[OliverWestby]

After further inspection, I have discovered that the compressor turns on for about 5 seconds, then off for about 30 seconds before trying again. I have cleaned the limescale and dust off the pipes and radiator, but no improvement.

One thing that occured to me it that there are a couple of old capacitors in the thing. Could they cause some of the problem if they have gone bad.

[slingblade]

After further inspection, I have discovered that the compressor turns on for about 5 seconds, then off for about 30 seconds before trying again. I have cleaned the limescale and dust off the pipes and radiator, but no improvement.

One thing that occured to me it that there are a couple of old capacitors in the thing. Could they cause some of the problem if they have gone bad.

Its fuc*ed mate. bin it and buy a new one.

[Brian_UK]

A bit confused about your "I've cleaned the pipes" bit. That post was one minute after you posted about "Having a look and it seems a bit scaled"

It used to take me about 30 minutes just to get all the covers off and the descaling could take several hours.

Just what chemical did you use to clear the scale ???

Also it might be worth considering a new unit, you've had good service for 14 years; let it die with dignity.

[OliverWestby]

A bit confused about your "I've cleaned the pipes" bit. That post was one minute after you posted about "Having a look and it seems a bit scaled"

It used to take me about 30 minutes just to get all the covers off and the descaling could take several hours.

Just what chemical did you use to clear the scale ???

Also it might be worth considering a new unit, you've had good service for 14 years; let it die with dignity.

It was actually 12 hours and 1 minute lol.
I got it off a mate for a couple of quid because it wasn't working, as a kinda project for the summer, so I was hoping to be able to fix it.
My latest troubleshooting/searching the net has come up with the compressor motor is getting stuck as it has been sat for a long time. I have come across this site that sells a device to attempt to jolt it free.
http://arnoldservice.com/air_conditioning_parts.htm
problem #2 on this page.

I dont really want to spend $20 on a special capacitor if I can get one from a shop for much less to do the same job.
I presume this just adds a boost of current to the capacitor allready in place.

could problem #3 also be a cause to my problem. I may just replace the capacitors and see what the difference is.

[Larry2]

You need to decide if it "cools slightly" or has the compressor "stuck from sitting". If the compressor stuck, it would not give you a moments cooling. It would be stuck and at best the fan motor would blow ambient air. If it's cooling momentarily and then the klixon shuts it off, your $20 kit isn't going to get it going because it's not physically stuck.

If the compressor has a run capacitor, it would be worth your time to measure it for short circuit, open circuit or correct value. The compressor can draw excess current if this capacitor is bad. That would cause it to cycle the klixon.

You may want to feel the pipes and decide if the compressor is really running momentarily or is it only humming momentarily before the klixon shuts it down. A stuck compressor will cycle as you describe, but it won't pump any gas and won't give any cooling at all.

[frank]

Sounding like a true Pro now Larry :D

[OliverWestby]

The pipes don't seem to change temperature at all, although the air coming out feels cool, however, I thing this is because the air is moving so feels cooler, in the same way a fan does.

My DMM doesn't do capacitance, but my mates does, so I'll have a go at testing later.

Cheers for all your help

[Paulajayne]

Any anybody asked if it has gas in it, and how much?


Just a thought ------

Paula