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sailing_gal 06-07-2020 14:12

Compressor replacement
 
I have an older SeaFrost DC5000 system and the compressor has decided to call it quits. Everything else in the system works fine. I would like to replace the compressor with a newer more efficient and quieter compressor. I am in Spain, and it is difficult to find things. Can anyone recommend a replacement for the 1/2 HP compressor that I have? My fridge is about 23 cubic feet with separate cold plate systems, one system for the freeze and a separate thermostat for the separate fridge. I figure I could probably make do with 2- 1/4 hp compressors as well.

Thanks in advance for any suggestions.

Turtle Blues 06-07-2020 14:26

Re: Compressor replacement
 
Rparts.com carries the Danfoss line with the power modules for various voltage setups

sailing_gal 06-07-2020 14:31

Re: Compressor replacement
 
It would have to be from a European company... So, I am looking at Danfoss over here, but having a difficult time deciding on the best one.
Quote:

Originally Posted by Turtle Blues (Post 3180246)
Rparts.com carries the Danfoss line with the power modules for various voltage setups


Richard Kollmann 07-07-2020 13:25

Re: Compressor replacement
 
Quote:

Originally Posted by sailing_gal (Post 3180232)
I have an older SeaFrost DC5000 system and the compressor has decided to call it quits. Everything else in the system works fine. I would like to replace the compressor with a newer more efficient and quieter compressor. I am in Spain, and it is difficult to find things. Can anyone recommend a replacement for the 1/2 HP compressor that I have? My fridge is about 23 cubic feet with separate cold plate systems, one system for the freeze and a separate thermostat for the separate fridge. I figure I could probably make do with 2- 1/4 hp compressors as well.

Thanks in advance for any suggestions.

How often and how long each day was it necessary to run an alternator to support refrigeration, or do you know how many daily amp-hrs your refrigeration requires?

Your present compressor is a modified automobile AC compressor You could purchase the new compressor only and install it inside condensing unit. from Seafrost. Off the self water cooled condensing unit may be hard to find outside the US. Air cooled AC 1/2 HP are common but voltage and 50 cycles may be a problem for you, also they produce too much heat inside a boat. Demedic in south FL still produces Grunert water cooled 12 and 24 volt condensing units in 1/2 HP I think this is your simplest direct replacement. Flush oil out of holding places remove old condensing compressor unit and adapt old condensing unit lines to fit new unit. You may be able to use the Seafrost thermostat and electrical wiring.

If the refrigerator box is less than 8 cu ft and freezer less than 4 cu ft or less you could use two air cooled BD50 compressor units, Frigoboat, Isotherm, Demedic But this would mean removal of holding plates and replacing them with standard evaporators assuming present plate evaporator tubing is larger than 5/16 OD. If you must keep the holding plates you could see If Technics maker of the Coolblue systems. could supply you a conversion condensing unit. If all else fails you could send pictures of system to Ozefrige in Australia.

sailing_gal 17-07-2020 03:38

Re: Compressor replacement
 
An update. Decided to replace the old Seafrost compressor and make use of the holding plates. I am having a system custom built using 2- 1/5hp Embraco compressors (Europe's answer to Danfoss), one for the fridge, and one with lower temp stats for the freezer. Have had water cooling coils made for each one. I anticipate finally being able to keep ice cream in my freezer! Will have to change the glycol mixture a little bit in the freezer holding plates to get there. I am giving each compressor its own inverter to run the system off of 12V. Therefore, I figure I will now have a redundant system. If one unit should fail, I have a completely seperate unit.

So, I had some time on my hands to take apart the old compressor---- if you are interested in what I found, pm me. It was pretty interesting.

Richard Kollmann 17-07-2020 13:27

Re: Compressor replacement
 
Be sure to use the Low Back Pressure (LBP) compressor for freezer application. This is link to Embraco compressors https://refrigerationclub.com/wp-con...N-02-03-18.pdf.
An invert er for each compressor is a good idea, unfortunately 12 volt to 115 volts with a 1/5 HP compressor is not very energy efficient. I would recommend TXV refrigerant flow control and small receiver tanks for both systems because of the eutectic plates.

sailing_gal 18-07-2020 03:08

Re: Compressor replacement
 
Quote:

Originally Posted by Richard Kollmann (Post 3188339)
Be sure to use the Low Back Pressure (LBP) compressor for freezer application. This is link to Embraco compressors https://refrigerationclub.com/wp-con...N-02-03-18.pdf.
An invert er for each compressor is a good idea, unfortunately 12 volt to 115 volts with a 1/5 HP compressor is not very energy efficient. I would recommend TXV refrigerant flow control and small receiver tanks for both systems because of the eutectic plates.

Thank you for the information. Both compressors are LBPs, have TXVs and rather oversized dryers (about 3") tall cylinders. Also I have high/low pressure switches installed. The person putting this together for me feels that a receiver tank is not necessary. Do you have a strong case for putting one in? I am converting from 12V to 220V here. I realize I may lose some efficiency, but probably very little.

Richard Kollmann 18-07-2020 15:12

Re: Compressor replacement
 
Quote:

Originally Posted by sailing_gal (Post 3188710)
Thank you for the information. Both compressors are LBPs, have TXVs and rather oversized dryers (about 3") tall cylinders. Also I have high/low pressure switches installed. The person putting this together for me feels that a receiver tank is not necessary. Do you have a strong case for putting one in? I am converting from 12V to 220V here. I realize I may lose some efficiency, but probably very little.

Sound good, I believe in refrigerant Receivers in mobile refrigeration as they tend to compensate for design errors we make especially with eutectic plates. The refrigerant flow volume requirement changes from max flow starting with a warm eutectic plate and as the plate reaches it low temperature the TXV cuts this flow in half. Normally with TXV's we store excess refrigerant in receiver tanks. I suppose your tech believes he can store excessive refrigerant in seawater condenser if he needs it, and he can be right because it is done sometime. Is he installing Refrigerant sight glasses because without them there is going to be little room for determining correct amount of refrigerant.

Coolerking 18-07-2020 18:26

Re: Compressor replacement
 
She might already have the receiver with the sight glass in the top that seafront supplies.

sailing_gal 18-07-2020 19:04

Re: Compressor replacement
 
Yes, I have sight glasses for both the fridge and freezer.
Quote:

Originally Posted by Richard Kollmann (Post 3189109)
Sound good, I believe in refrigerant Receivers in mobile refrigeration as they tend to compensate for design errors we make especially with eutectic plates. The refrigerant flow volume requirement changes from max flow starting with a warm eutectic plate and as the plate reaches it low temperature the TXV cuts this flow in half. Normally with TXV's we store excess refrigerant in receiver tanks. I suppose your tech believes he can store excessive refrigerant in seawater condenser if he needs it, and he can be right because it is done sometime. Is he installing Refrigerant sight glasses because without them there is going to be little room for determining correct amount of refrigerant.


sailing_gal 18-07-2020 19:08

Re: Compressor replacement
 
Also, I have over 2 meters of condensing coils... 1/4" copper pipe inside 1/2" radiator hose that will have seawater cooling.

sailing_gal 18-07-2020 19:26

Re: Compressor replacement
 
Oops, I think that is 1" radiator hose.....
Quote:

Originally Posted by sailing_gal (Post 3189236)
Also, I have over 2 meters of condensing coils... 1/4" copper pipe inside 1/2" radiator hose that will have seawater cooling.


Richard Kollmann 19-07-2020 11:11

Re: Compressor replacement
 
Things are looking good for your refrigeration venture. I do not like to point out the fact that the electric compressors with seawater cooling condensers discharges low voltage into seawater inside condenser. This is why refrigerant tubing submerged inside condenser is usually cupranickle. This low voltage corrosion rate is unpredictable failures on cupranickle condensers in tropical salt water can occur at 10 years of use. Sacrificial Zincs are used on some condensers.

sailing_gal 19-07-2020 12:20

Re: Compressor replacement
 
Interesting... will look into that. Never heard of that issue. My old condenser was biaxial solid copper, no corrosion evident after 20 years. Decided to add receiver units just to be conservative. Thank you for all of your input.

Coolerking 19-07-2020 19:34

Re: Compressor replacement
 
Ill bet you had a Cu-Ni condenser.


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