Carrier Ultra Reefer Unit, mid 90's

[CA51]

Hello,
I'm considering purchasing a mid 90's Carrier Ultra Reefer unit and modifying it for use on my commercial fishing boat so that I can freeze salmon and albacore at sea.
Does anyone know what refrigerant should be used to get temperatures below -20 F?
Or if this unit would even work for this application?

Thanks,
any info on the Carrier Ultra would be appreciated.

[abbsnowman]

I have seen this done before. Usualy with a truck unit though. It's not difficult to seperate the evap on the truck units.
R22 or R404a that is already in unit is fine for frozen.
I don't like working on these things but they do work. Make sure you get somebody that knows what they are doing.... service calls 3 miles off the coast can be costly! :D

[CA51]

What is it that you don't like about working on these units?
It's a unit taken off a trailer that had damage to the roof.
I think it has a Kubota engine. My plan is to separate the evaporator like you said and mount the engine/compressor in the engine room of my boat. I'm probably biting off quite a project.

Thanks for the reply

[abbsnowman]

The reasons are:
- usualy the componants are jammed in small, hard to get at areas.
- salt water does really nice things to wiring and generaly everything in there.
- Boats are kept in water, service truck is on land, I'm lazy.... lol
- when they break down, they are, as mentioned, 3 miles off shore.
- I don't work for fish.

Truth be told, I have met allot of really great people working on these and it's tough when you have to give them bad news or tell them they are going to go broke trying to keep this thing running.
Like I said, they work great when they work.
Your in Washington? Maybe you should just sell me the unit? lol

[CA51]

lol, yeah, being out in the middle of nowhere can be a big problem.
Can most of the electrical be removed from a unit like this? Then just use the engine/compressor, evaporator, with manual valves for defrost? that's kind of what I'm planning, I'll need to use a water cooled condenser anyway.

lol,, I'll take a good look before I tear into it.. maybe I'll just sell it to you.. : )

[jit]

No 1 problem is if the unit carcass has significant delamination in which case will struggle to pull down and hold.
Check by walking on floor and if it goes up and down or is firm, plus the roof and walls if you push them to check.
2. Do you know what model the machinery is. Should be 69NT xxxxxxx.
I wouldn't look at using it if you are in higher ambient temps and there is signs of delamination.

[abbsnowman]

No 1 problem is if the unit carcass has significant delamination in which case will struggle to pull down and hold.
Check by walking on floor and if it goes up and down or is firm, plus the roof and walls if you push them to check.
2. Do you know what model the machinery is. Should be 69NT xxxxxxx.
I wouldn't look at using it if you are in higher ambient temps and there is signs of delamination.



Huh??:D


CA51,
The electrical should really not be altered unless you really know what your doing.

[Boss302]

I hate it when the carcass gets delaminated

[CA51]

does anyone know where you can purchase the service manual for Carrier Ultra Phoenix? lol, I bought it.

[CA51]

I hate it when my carcass gets delaminated LOL

[abbsnowman]

does anyone know where you can purchase the service manual for Carrier Ultra Phoenix? lol, I bought it.


I would have sent it to ya for free.

[CA51]

ok, I'll take it for free, do you have it in pdf?

[abbsnowman]

Shall I guess your email?? :D

[CA51]

oops, that's right, probably can't send it without email.

salmontroll@hotmail.com

thanks!

[abbsnowman]

You have mail...

[CA51]

well, I'm running into space limitations to mount this unit... I'm thinking I'll have to disassemble, then mount the evaporator and condenser in a different location from the engine/compressor, lower blowing into the hatch combing/fish hold. Also it looks like I'll have to convert from R 22 to R507 to get to -30 and lower. getting interesting, If I reassemble it side by side, I'll have to figure out a way to run the fans... dang I wish it was about two feet shorter!

[abbsnowman]

You are getting in pretty deep. If you really want to do this, let me say again, get a truck unit or even better, a hvac unit.
Of course if you must throw money away, I would be happy to come down and pick it up for ya!:D

[CA51]

Things are moving ahead on this reefer project.. The unit works GREAT!, I'm almost ready to have it craned onto the deck.
One question,, it's a R 22 unit. I know I'll have to change to a lower temp refrigerant.. 507 most likely.
I see the new units are sometimes using R 407 A. Is this a better low temperature refrigerant than R 507???

[abbsnowman]

Those units used R22 and hauled frozon for years. R22 is cheap, (for now) why change it? It will be phased out but not yet.

[CA51]

I'd like to get the fish hold temp to -30F or below, I guess I'll finish the installation and see how low it goes using R22

[Oregonbythesea]

You're going to have a hard time getting that unit to anything less than -20 and even then you are going to find that you'll be in defrost a lot if you can manage to catch enough salmon to make a good day. As for tuna, you won't be out of defrost with the coil spacing to make it worth while. Those units were designed and built to hold a frozen product is a fairly dry area. Fish boat holds don't meet those requirements. They were never designed as low temp processing units. There are units mounted on decks within boxes that seem to work. Just make sure you know someone who can work on it or start learning how to keep it running.

[CA51]

Are you saying I should modify this unit with an evaporator with more space between the coils? snd maybe also use a water cooled condenser instead of the air cooled? I sure don't want it to be in defrost all the time when I need to get product down.

Thanks for the help!

[Oregonbythesea]

Yes, I guess I am. I can assure you right now that you would have been better off to sell that unit as a working one to someone who could put it back on a trailer. A marine evaporator isn't really much different except that the old ones were designed to be in the trailer rather than the air being transported in and out of the unit hanging on the outside. The fin spacing for marine freezing should not be more than 5 fins/inch. A marine condenser must be made of cupro-nickel interior tubes for salt water. Now, for using the engine and compressor combination, it was designed to work with the loads available with the exiting circuits. If you change those to have the capacity that is available, you will have that little unit slobbering oil within one season. I am just giving you information that I have learned over the past 30 years with these conversions and would suggest you get a trade magazine like "The Fisherman's News" and contact a company that builds the type of unit you are trying to make. Believe me when I say you will probably have twice as much invested in a good system going it on your own by the time it is done. Good luck on whatever you choose to do.

[CA51]

I decided to keep the unit intact and mounted it on deck, with a freezer box. It worked really great, I used it this season to keep the hold cold for the flake ice, keeps it really nice and flakey. Had problems with freezing though, it takes the hold down to 0 degrees in about 10 minutes and won't go any lower. The evaporator isn't frosted up, and it drops the temperature to 0 so efficiently I'm wondering if it could be that the expansion valve could be limiting the reefer from sub zero temperatures? Or if anyone knows, could it be that R 22 won't go to -30? the computer has settings up to -22 so I'm guessing some Carrier phoenix ultras should get that cold?
anyone have an idea what to look for?

[Oregonbythesea]

If the unit drops the temperature down to 0 really quick and won't go any further than I would look at the hot gas valve and make sure it isn't partly open. Also, some units had a temperature control for fresh produce that I am not at all familiar with. This is the point where you will need to call someone who can check out the operation and see if they can figure it out with a "hands on" approach. There are a number of things that can cause what you describe on a fishing boat.

[CA51]

thanks for the ideas. the compressor has hot gas unloaders I think. It could be that these are being activated by the computer when the temperature reach near 0. Looking at the service manual there is something called "ultra fresh" control which cools and heats to keep fresh foods at a set temperature. I think this is bypassed when set to temperatures below freezing though. it very well could be a software issue. I think there's also a way to bypass the computer, and run manually , in case of an emergency(computer failure). I haven't figured out how to do that yet. but it'd be interesting to see if it would pull down below 0 degrees when the computer is bypassed.

[Oregonbythesea]

If your insulation is at least a couple inches and the hatch is sealed, you should get down to -20F and if everything is great, you could reach -35F fairly easy. The colder it is set, the less it will freeze at that temperature. -20 is a good setting for the best all around results. Good luck and at these prices for tuna, it will be worth the time to make sure it works best.

[CA51]

Does anyone know how to bypass the computer on a Carrier Phoenix ultra? The unit only cools to 0 degrees. I want to try test running the unit without the computer. I need it to cool to at least -20F and am wondering if software is limiting the temp.

[Oregonbythesea]

Hi Ca51, I don't know how to use their computer if it won't go below 0. I just rewired an ultra using a Johnson Control MR4P controller. It operates with -35 air off the evaporator with no problem at all. Good Luck. I did change the condenser and hot gas circuits to be more standard.

[gravy258]

Can you set up a temperature analyser to see what the temperature difference is across the evaporator coil ?

do you have the operation and service manual for this unit ? A good read of this might help you out. I believe i might have it if you want.

the micro is a solid state controller, nothing smart about it like later models.

Also put up some pictures of your set up, it will help us to help you.

[cadwaladr]

use an ice making machine forget trying to adapt a reefer unit too costly if you cover your harvast/catch in flake ice then it will be kept in a state that is acceptible to buyers the system works fine over here try ziegra .com

[Oregonbythesea]

Ice is not acceptable for his catch. Besides, ziegra is way too expensive. I should say, ice is not a viable way for a West Coast Tuna boat to make any money. It often requires at least a week at sea to fill the boat while the buyers will only accept up to 3 day old fish. A lot of times the ice is melted before the fish are located. Blast freezing pays better than fresh anyway.

[CA51]

Hi Oregonbythesea, Happy New Year!


that's interesting, I'm curious why you rewired the ultra with a Johnson Control MR4P? I'll have to look at that controller.

[CA51]

Hi gravy258,
yeah, I have the service manual, been over it several times, I'll look into measuring the temps across the evaporator, good idea. I was also thinking of testing the voltage on the hot gas valves to see if it is opening to keep the temperature from dropping lower.

[Oregonbythesea]

Sounds like your getting there. As for the hot gas valve leaking, you should be able to just put your hand on the line. If the valve is leaking, it will be getting very warm or even hot. The line should be cool or room temp to know it is closed. Good luck.

[Boss302]

Does anyone know how to bypass the computer on a Carrier Phoenix ultra? The unit only cools to 0 degrees. I want to try test running the unit without the computer. I need it to cool to at least -20F and am wondering if software is limiting the temp.

You aren't going to gain anything by bypassing the micro. Any setpoint +10°F and lower and Ultrafresh is disabled. I have seen R22 Ultras running at -36°F and that is all the colder the micro will read. Don't expect it to do it on a warm ambient day. If you are set at -22F and the box temp is at 0 the unit is doing everything it can. Make sure it is running fully loaded. You could have a problem that is making it unload some cylinders. Amb. temp sensor, Suction pressure transducer etc...

[CA51]

Had a fair amount of success.. cleaned wiring connections, and unplugged the unloader connectors, then ran the unit for 2 hours set at -22(lowest temp) after two hours the box temperature on the computer read -28, my cheap thermometer in the fish hold showed -10. Does anyone know if running the unit with the unloaders unplugged will cause damage? getting closer, but would like to be at -30 in the hold.

[Oregonbythesea]

You may get the hold down to -30 if you can keep the unit running without it cutting out on temperture set point. There was another comment on why to change the controller so I thought I would address that too. These units in fishboats are not standard and need to be kept running. We normall cut out all the auto stuff and just operate the units as standard electric refrigeration units and that is hard to do with the Transicold controller. The Johnson controller will bottom out at -40. As for the boat, it is not unusual to see the air off the evaporator at -40, or lower, while the hold temp is controlled at -25 or so. However, keeping the hold at a constant temperature is way more important then just getting it as cold as possible and then having it go up and down every time some product is added.

[cadwaladr]

is there any pics of this finished project?

[CA51]

85828583858485858586I'll take some pictures next time I'm working on it

[CA51]

85878588858985908591

[CA51]

When the unit hits it's -22 set point the engine slows, although still gets colder since the unloaders are dissconnectd. Next time I work on it, I'll have to take a look at the throttle control, maybe there's a way to set it to run full speed? Oregonbythesea, does the Johnson control computer plug directly into the Carrier connectors? or did you have to do some wiring?

[Oregonbythesea]

The unit would need to be completely rewired to use the Johnson controller. However, you end up with much less wiring in the unit. It takes a major change in the unit to make it work. If you are using it as it was manufactured, it is best to keep going like you are. As for the slowing down, you can disconnect the wires to the two speed relay and set it to run at whatever speed you want. I don't know if uses a fuel shutoff to stop the engine or releases the solenoid on the injector pump so be careful. We have been stripping those units down to a bare system and most of the time we remove the engine and compressor and replace it with a new scroll. We use a controller from here weissinstruments.com when we need a 12 volt one.

[IRMechanik]

to keep the unit in high speed, set the function to high air. Will still start in low speed then stay in high speed after water temp is past 76 degrees and will still drop to low speed after defrost to energize the clutch. The only problem with leaving the unloaders unplugged is start up, in high ambient it may have a rough time starting.

[Oregonbythesea]

I see by the pictures that you are freezing on deck. In that small space it should work great. Also, IRMechanik is right when he points out the starting problems with an unloaded compressor. We always change the piping so the system pumps down into the receiver when the temperature is reached. That way, there isn't a lot of torque on the compressor when it starts.

[IRMechanik]

or if the unit has a prestart buzzer, rewire the unloader relays to the prestart buzzer circuit. I'd say the glow plugs but in high ambient the unit probably won't preheat.

[CA51]

I was worried about that, that the compressor would have to start at full load, but at least it's at a lower rpm for the first several minutes. I'll have to look at the prestart circuit, or maybe a way to switch them on and off manually.
The unit is on deck blowing into that insulated box I built, the plan is fish are placed directly on racks or shelves in front of the evaporator, then when frozen removed and stacked in the fish hold below, it's all open, there's a side door and floor, a ladder down the the hold, doors on the back to load fish into from the back deck.. so far running it for a two hour test there was a difference of around five degrees from the front crossing down in the fish hold, to the upper box.

[CA51]

I'm interested why most marine blast freezer systems I've seen are using R507, or 502? mine, well not marine but using it that way.. Phoenix Ultra(R22)is blowing cold, but wow does the ambient air temperature make a difference. I'm going to add some more insulation in the fish hold, under the deck, it only has a couple inches also might help.

[Oregonbythesea]

In marine units, I only use 22 when it is an RSW system or brine freezer. For air blast, I only use 404a which is available just about anywhere. We used to use 502. 404a is about 10 degrees colder at the same PSIG as 22. I know of a 22 system running at -80F. It's all about sizing the system, air flow and horsepower. It sounds like you have more insulation problems than anything. Remember, heat only goes to cold and the bigger the difference, the faster it moves. Any air leakage around hatch covers, or openings, will cut down on the freezing ability of your system.

[cadwaladr]

I'm interested why most marine blast freezer systems I've seen are using R507, or 502? mine, well not marine but using it that way.. Phoenix Ultra(R22)is blowing cold, but wow does the ambient air temperature make a difference. I'm going to add some more insulation in the fish hold, under the deck, it only has a couple inches also might help.great pics,i could not imagine what you were doing with this unit but hey it looks good ,insulation is the key .