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scottishladx
24-07-2008, 01:52 AM
Here's a belter a 6 meter display cabinet directl opposite a window (solor energy etc) No curtains counter side place is like a green house :pcomp was a 5/8 hp aspera.

Wasnt short of gas, sight glass clear, dryer warm suction linefelt good condenser clean all fans working compresser running 24/7 coudnt go below 14degrees .

Rattled some 404 in on the suction side in liquid temp started dropping then u guessed it comp went chug chug grrrrrrrrrr.

If i put a 3/4 pot in would i have to change condenser and fan etc?

thanks

please keep this simple

scottishladx
24-07-2008, 01:57 AM
Here's a belter a 6 meter display cabinet directl opposite a window (solor energy etc) No curtains counter side place is like a green house :pcomp was a 5/8 hp aspera.

Wasnt short of gas, sight glass clear, dryer warm suction linefelt good condenser clean all fans working compresser running 24/7 coudnt go below 14degrees .

Rattled some 404 in on the suction side in liquid temp started dropping then u guessed it comp went chug chug grrrrrrrrrr.

If i put a 3/4 pot in would i have to change condenser and fan etc?

thanks

please keep this simple


Yes i was watching amps on compressor and controlling with my gages 3-4 psi above running pressure.

GXMPLX
24-07-2008, 02:16 AM
Once I had a Scottish classmate, and I couldn't understand a word he said!

My English lit teacher was Scottish too, and you guessed it I almost flunk!

At least my classmate turned out to be Ok ... can't remember his name though!

If you are saying that the compressor finally stopped when you charged more gas:


first I thought this was illegal in your area.
You said the system wasn’t short of gas yet you poured some more in.
Then the compressor went chug chug, does this mean it never started again?
A 3/4 pot of what size?


I don’t think you need to change condenser nor fan, just call someone that knows what he’s doing!

And long live Scotn’! as my classmate used to say when asked where he came from.

scottishladx
24-07-2008, 02:37 AM
Once I had a Scottish classmate, and I couldn't understand a word he said!

My English lit teacher was Scottish too, and you guessed it I almost flunk!

At least my classmate turned out to be Ok ... can't remember his name though!

If you are saying that the compressor finally stopped when you charged more gas:


first I thought this was illegal in your area.
You said the system wasn’t short of gas yet you poured some more in.
Then the compressor went chug chug, does this mean it never started again?
A 3/4 pot of what size?


I don’t think you need to change condenser nor fan, just call someone that knows what he’s doing!

And long live Scotn’! as my classmate used to say when asked where he came from.

Sorry chief been a very long day !

Yes the comp stopped running,it was a touch short of gas but i think the comp and compressor was well under sized for the size of evaporator.(2nd and cabinet)t called for cooling, fan kicked in 240 to pot No working comp is fecked

Illegal to do what exactly ?

Just re-newed my refrigerant handling last week so nothing was illegal ?????

My spelling aint great but yes i am a qualified fridge engineer mainly a/c service and install for the last 8 years but Just finished my mature apprenticeship as a electrician +17 edition.

UT2178GK 5/8 947 1023 C-V 20.4 CSR 3/8" 1/4" 477 353 303 N16-30

GXMPLX
24-07-2008, 02:51 AM
Illegal to charge systems that leak without resolving the leak first.

Good, then you do know what you'r doing ... then I didn't understand the post! Was it supposed to be funny? ... I'm an expert at bad jokes!

Don't you worry your spelling is much better than mine!

Don't post personal information.

Still don't think you need to change the condenser nor fun unless your condensing pressures are high and the system is not overcharged.

But you do need to protect the system from direct solar radiation and infrarred too.

Hope this helps!

Electrocoolman
24-07-2008, 10:29 AM
As per your request to keep it simple!!!



"Please keep this simple"

Rattled some 404 in on the suction side in liquid ..... then u guessed it comp went chug chug grrrrrrrrrr.



Compressors don't like liquid 'up them'!!

They tend to react as you have discovered the hard way.
What was superheat reading?



a 6 meter display cabinet....comp was a 5/8 hp aspera.



What type of cabinet? Serveover or a multideck? I dont think its got a hope in hell with that size compressor in that run of cabinet (6 METRE!) solar gain or no solar gain.
What is being displayed?
For a dairy multideck you are going to need at least a 2HP unit for each 3 Metres.



If i put a 3/4 pot in would i have to change condenser and fan etc?


No, but it might be a waste of money without doing some calculations first.


It sounds as this is a 'pig in a poke' of a unit....2nd hand you say !!!

What you need to do is start from scratch....what is design temperature..(dont forget about type of defrost..ambient or electric), find out refrigeration load from cabinet manufacturer, add allowance for ambient conditions, (might be better remoting cabinet to get rid of heat and noise), multiply heat load by 4/3 to reduce running time of condensing unit

Don't forget a lot of these cabinets are rated fot 25deg C ambient....you need to take this into account.
Also check for condenser air recirculation!
Also is it near doors or in a draught....blowing cold air out of cabinet?

Good luck.

scottishladx
24-07-2008, 11:13 AM
Illegal to charge systems that leak without resolving the leak first.

Good, then you do know what you'r doing ... then I didn't understand the post! Was it supposed to be funny? ... I'm an expert at bad jokes!

Don't you worry your spelling is much better than mine!

Don't post personal information.

Still don't think you need to change the condenser nor fun unless your condensing pressures are high and the system is not overcharged.

Thanks mate but it can be very hard to find a leak ina 6 meter evaporator even pumped to the hilt wi nitro

Yes liquid into comps dont like it but if you go by listening to comp and watching amps your generally ok i was unlucky this time eeeek.

The guy wanted a quick fix the condensing unit comp etc has been chucked in spare lying around and sold just attached to the underneath of the cabinet added new tev.


feck it i willl look at maybe gettinmg at outdoor unit think its the easiest option in this case regarding h=eat etc.





I will do my sums

But you do need to protect the system from direct solar radiation and infrarred too.

Hope this helps!

Thanks mate but it can be very hard to find a leak ina 6 meter evaporator even pumped to the hilt wi nitro

Yes liquid into comps dont like it but if you go by listening to comp and watching amps your generally ok i was unlucky this time eeeek.

The guy wanted a quick fix the condensing unit comp etc has been chucked in spare lying around and sold just attached to the underneath of the cabinet added new tev.


feck it i willl look at maybe gettinmg at outdoor unit think its the easiest option in this case regarding h=eat etc.


i will do my sums

GXMPLX
24-07-2008, 03:37 PM
I think you should read this post of Chunk, but there are other on RE that may help if you search them.
http://www.refrigeration-engineer.com/forums/showthread.php?t=13119

The information you first gave wasn’t enough to tell if you should change the condenser or not and the best option in these cases is to reduce the thermal load like I posted because in the end you will not be able to change the evaporator, and you may have to.
If you are going to move the compressor then you really need to calculate if you need a bigger one and take notice on suction line design problems.

Answer Electrocoolman’s post including the model of the compressor, you know Aspera or now Embraco does not publish HP ratings for at least 20 years now, they are misleading.