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Krups
12-06-2004, 03:13 PM
iv been given a lec r.503w running R12 domestic to have a look at, its not cooling at all freezer or fridge, compress is very hot to touch.
basic instincts point me to either a tstat fault or lack of gas ?
am i right in thinking this ?
what else could it be ?
thanks in advance

chemi-cool
12-06-2004, 03:35 PM
Lack of gas I would guess but check for blocked filter as well.

Chemi

frank
13-06-2004, 05:53 PM
Krups

The first thing you must do under UK law is recover and send for destruction, the refrigerant. We are not allowed to work with R12 anymore.

Now, from the symptoms, it would appear that the compressor is hot due to a lack of refrigerant suction gas cooling and the lack of refrigerating effect is also due to a lack of refrigerant.

Got to agree with Chemi on this one - looks like a lack of gas charge or a blockage.

Latte
13-06-2004, 06:27 PM
Hi Krups,

The Compressor is still running so that kind of rules out stat.

As everyone else says it's either lack of gas or blockage.

check the drier either side, does it feel the same temp if yes then poss rule out blockage. As Frank say's R12 you have to do by the book. Reclaim the gas & pressure test. If you find a leak repair it if not try to blow OFN through the system to double check blockage as i assume the unit is on capillary so these easily block up.

I assume this is a theory/practical test so you have to play it by the book but unfortunatly in the real world 90% of the time by the time you pay labour charges it's often cheaper to buy a new unit.

When you reclaim the gas weigh it, this will give some indication if the charge is low, just check on the manufactures label it should tell you what the factor charge is

Regards

Raymond

chemi-cool
13-06-2004, 06:46 PM
Hi Krups,

Yes, Raymond has a good point.

If you work out the cost of recover, new dryer, drop in gasor in the worst case, a new compressor and all the time.

A new unit will be cheaper.

Dont even start looking for a leak.


Chemi

Abe
13-06-2004, 08:35 PM
Krups

r12........so is an old fridge. Often on these units the valve plate fails..........hook your gauges.......if back pressure does not fall on start up.............fit new compressor.

Essential u hook up gauges..........if it goes into vacuum..........blockage, either in drier or cap tube. These dont have access valves.......use LT4G access valve from RPW . Watsco

But ..........either way not worth repairing., unless you want to use the experience to learn the trade.

Brian_UK
13-06-2004, 11:04 PM
Abe, he can't fit gauges as it is an R12 system.

Maintenance/service work can NOT be performed on a CFC system in the UK unless it has an exemption.

As Frank said earlier all that can be done is to recover the refrigerant for disposal.

Overall my suggestion would be to pay the disposal charge levied by the local waste management centre and buy a new fridge.

Abe
13-06-2004, 11:08 PM
Thanks Brian

Well, sorry, seems I was asleep about the regs...........but thanks for updating me .

Pieheid
21-06-2004, 12:58 AM
Compressor may not be pumping properly... :cool:

Abe
21-06-2004, 08:44 PM
Your " handle" about sums it up !
:D

Pieheid
21-06-2004, 11:10 PM
Well i thought i was trying to help, as someone who many many years ago worked on a lot of Lec fridges and frequently had this problem, i would fit an ltv and then guages to find a pressure of 50-60 psi, compressor running but not pumping, if i made a mistake in trying to help i'm sorry. By a strange twist of fate i was working on a lec fridge today {i think a 550 running on 134a} in an Edinburgh hospital and it had the same fault. :)

Brian_UK
21-06-2004, 11:13 PM
Your " handle" about sums it up !
:D
Talk about ROFL Abe, you got me going there.. ;) :D

frank
22-06-2004, 08:42 PM
Ayb - you crease me up ! :)

Abe
22-06-2004, 10:41 PM
Piehead

Im glad you said it was R134A........But full marks to you........
I think your prognosis........was about right!!
Its the evil R12..........systems that we dont want to play with. there dastardly.........especially for you folks up north....the ozone hits you guys first.....

Krups
04-07-2004, 04:58 PM
hey thanks every1 for all ur help....its good to have guys like u who are so helpful to newbies like me....one day i hope i can do the same for others....
cheers folks, i will recover and get disposed of and see what the fault is from there....

Abe
04-07-2004, 05:53 PM
Krups,

Save your time, That unit is Crap, ( pardon the pun)
Head for Comet........or Iceland.......

Abe

Krups
04-07-2004, 11:19 PM
lol the only reason im doing this is just for practice....and i think of it as a hobby.. if you will(i have a lot of time on my hands!) :p

bigjoe
07-07-2004, 03:01 PM
Krups , I am also a refrigeration hobbyist..learnt the crap

some 30 odd years ago and wondered off to other things.

I want to give you the bicycle pump analogy : If you're

pumping to the open air the pump never feels hot ; if you're

pumping into the tube, after a short while the pump

exterior gets hot. Forget the physics involved...the idea is

that in the latter scenario you're pumping against something.

That something is a blockage on the highside. It will

generally take a long while for a gassless hermetic

system to get the compressor hot.

chemi-cool
07-07-2004, 03:18 PM
generally take a long while for a gassless hermetic systems to get thecompressor hot

Wrong my friend. ;)

The returning gas is cooling the compressor, without it, it gets hot very quick.............and burnout.

Chemi

bigjoe
07-07-2004, 10:19 PM
Chemi , I agree to disagree with you. Have you ever
taken out a pot from the sealed system ..run it .....
see how hot it gets and its longevity? I have had one
over 3 years plus ..used it as a vacuum pump among
other things and I can vouch that it gets nowhere
hot as when in the sealed system. Point to note is that
once outside it is bereft of the cool/cold vaporised gas
and does not die an instant death.

"I may not agree with a word you say, but I will defend
to the death your right to say it."

Latte
08-07-2004, 02:59 AM
[QUOTE=Brian_UK]Abe, he can't fit gauges as it is an R12 system.

Maintenance/service work can NOT be performed on a CFC system in the UK unless it has an exemption.





Hi Guys,
Call me thick but am i missing something here :confused:

Surely you can fit a tap valve in the system to fit gauges, you would have to fit one anyway to reclaim the gas so whats the difference, i was under the impression that as long as you didn't vent to the atmosphere you were ok.


Regards

Raymond

Tates_uk
10-07-2004, 12:33 AM
[QUOTE=Brian_UK]Abe, he can't fit gauges as it is an R12 system.

Maintenance/service work can NOT be performed on a CFC system in the UK unless it has an exemption.





Hi Guys,
Call me thick but am i missing something here :confused:

Surely you can fit a tap valve in the system to fit gauges, you would have to fit one anyway to reclaim the gas so whats the difference, i was under the impression that as long as you didn't vent to the atmosphere you were ok.


Regards

Raymond

Agreed!

OK to fit guages to 12, not to posess, vent, put back in after major works (IE comp change).

Can't see any reason not to apply guages as long as it's done responsibly and correctly.

Can I 'ave me skill card now....??!!??

Abe
10-07-2004, 01:13 AM
Now u tell me ??? After Brian put the frighteners on me..........I went to a couple jobs where I saw R12 emblazoned on the pot!!

I shrunk back from the unit............and condemmed it right away............

Interlevin are laughing all the way to the bank...........each one bought a new cabinet!!!!

hhbref2003
11-07-2004, 03:06 AM
Krups.

The compressor may be working. But there is another thing to find out and that is its pumpimg efficiency. However, unless you can recover the R12 and have more to top up . I would recommend you to simply scrap away the compressor and replace it with a new R134a for example. Clean the piping circuit before connecting the new compressor and replace with a new filterdrier as well.

A lot of precious time would have been saved.

Huba

AZboyinWI
11-07-2004, 09:37 PM
I have to agree with all the earlier statements. Here in the states if we run into an r12 unit, it just isn't worth the time to mess with it, if the problem lies in the refrigerant loop. By today's standards it is much easier/cheaper to purchase new. Also while doing servicing work, it just isn't good customer relations/business sense to make a repair on a unit that old , then have to return within a week, because something else has failed. Customers just don't understand that. I try to always give good advice and recommendations so they will see it my way.

dwarthstar
11-07-2004, 10:11 PM
I would have to agree, on changing the r12 pot's,, i work for a vending company and we probably change one a week, and neally all are cracking on abit in years so y chuck money on lots of repairs when you can fit a new 134a pot, as cheap as chips, and saves a lot of hassle later..
PS while i am here can anyone tell if venting isobutane, or butane, to the atmosphere is ok in small amounts, say 300 to 400 grms, taking into concideration, that i will put me fag out befor i did it,,,naturally.... cheers chaps,
steve : :confused:

bangoman
15-02-2006, 09:46 AM
Hie all .had a domestic fridge comp runing hot and trips,but when it starts cools well then prob starts again.checked to find a pencil drier full of oil and dirt .Checked the condensor was clean.Wil blow condensor,change oil ,change drier and charge the sytem.Am i on the right track coz wondering how the oil got to mess the the silica gel in drier.

bangoman
15-02-2006, 09:49 AM
Hie all .had a domestic fridge comp runing hot and trips,but when it starts cools well then prob starts again.checked to find a pencil drier full of oil and dirt .Checked the condensor was clean.Wil blow condensor,change oil ,change drier and charge the sytem.Am i on the right track coz wondering how the oil got to mess the the silica gel in drier
:confused: :confused: