Aquarium Chiller Questions

[HVAC_Marc]

Hello! Let me preface by saying I'm no refrigeration tech but I do have my Universal AC certification. I understand the basics of refrigeration only. I may be making my problem more complicated than it needs to be.

I have an aquarium chiller that has a custom made heat exchanger. The company that made the unit has gone out of business. There is no documentation. The main chassis and compressor are still made. See the specs below:
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Copeland M2FH-0026-IAA-102

Compressor: AR27CIE-IAA-100

DT Code 19A00

Max Evap Temp = 45 degrees F

It's single capillary tube metering.
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The model number translates to: M series, R-134a, Air-Cooled, High Temp, Revision 0, 1/4 HP, 115 volt, 1 phase, 60 Hz, no valves

The compressor model number has changed, the specs haven't. I have a new compressor in the box.

The problem is that this unit was designed to be an air to air unit versus and air to water unit. The custom exchanger is an 8" long, 3" PVC pipe shell with a 3/8" diameter titanium coil of some sort inside. Length and configuration are not known. 575 gallons per hour of 1.027 salinity sea water flows though 1" connections. In the past, there was a 1 degree F drop across the exchanger (at 575 gph).

The Copeland spec sheets have no information regarding minimum system charge to keep the compressor cooled. Any kind of exchanger should be "add X amount of charge per foot of tubing". I have spec sheets for both the air M2FH and water M2WH systems. Both say:

BTU Capacity at 60 Hz with 5 degree F subcooling.
HT Models are rated at 65 degree F return gas temperature.

The system was working fine per the customer with the exception of the compressor making a huge rattly noise on shut down. It was very wobbly like a spring support broke. I weighed the recovery cylinder before and after the evac process and found only 5.8 oz of refrigerant had been removed. It doesn't sound like enough but I have no frame of reference.

Should I ignore any presuppositions I have and charge based upon the spec sheets even though there is a non-standard heat exchanger installed? My concern is that there may not be enough charge to properly carry oil through the system. Temperature shouldn't be any problem. Then whatever comes out the chilled side "is what it is" right?

I will be adding service valves to the system. Would it be OK to add a small filter drier on the compressor outlet? Does someone have an actual working phone number for Emerson/Copeland Tech Support? I registered for the Emerson site but it pukes when I try to log in.

[jayguy]

Hello! Let me preface by saying I'm no refrigeration tech but I do have my Universal AC certification. I understand the basics of refrigeration only....

i am a big fan of the tv drama 'House'...does that qualify me to perform surgery? having a 1/2 hour class to get a piece of paper is not the same as being qualified to work in this industry.

...The system was working fine per the customer with the exception of the compressor making a huge rattly noise on shut down. It was very wobbly like a spring support broke...

sounds to me like one of support springs (internal to the compressor) broke...but why? install your new compressor and it may happen again because you are not qualified to understand the intricacies of how it really works...not just understanding the basics.

...I will be adding service valves to the system. Would it be OK to add a small filter drier on the compressor outlet? Does someone have an actual working phone number for Emerson/Copeland Tech Support? I registered for the Emerson site but it pukes when I try to log in.

adding service valves and filters changes the game a whole lot. this doesn't mean that it can't be done and still work, but how much extra refrigerant are you going to add VERSUS how much should you add? if you got in touch with Copeland tech support, they will not talk to you about your SYSTEM, they would only tell you about the model number of the compressor (which you seem to already know) and what capacitor it takes, etc. wherever you bought the compressor is who you need to talk to about technical support, however, i suspect they don't know jack about it anyway. the companies that represent and sell Copeland products (properly) in the Midwest wouldn't have sold it to you anyway....well, except for 1 very large and nationally known company. they would sell it to you, but they don't know jack about anything in this industry except how to take money from anyone.

you need to call a reputable company in your area. it will be faster and cheaper...i know you think that it won't be cheaper, but in the long run, it will be.

good luck.

[ga1279]

"I'm not an HVAC expert" I'm not going to dwell on that as Jayguy has already done this. While we are mentioning TV shows, how about contacting the guys at "Tanked" on the Animal Planet channel. As they have unique solutions to aquarium related problems. Do you know what tank temperature you are supposed maintain. You are trying to move a lot of water through a relatively small heat exchanger. You did not mention the length of your 3/8 diam. tubing, but 9.6 gpm sounds a bit on the high side your velocity of flow is way to fast, about 20' per second. That doesn't give you a lot of time to cool the water, salinity or plain water.-GEO

[Tech Rob]

You are trying to move a lot of water through a relatively small heat exchanger. You did not mention the length of your 3/8 diam. tubing, but 9.6 gpm sounds a bit on the high side your velocity of flow is way to fast, about 20' per second. That doesn't give you a lot of time to cool the water, salinity or plain water.-GEO

I was thinking the exact same thing. Could be why his delta T is so low. The OP has got enough water flow for almost 4 tons of cooling.

[HVAC_Marc]

i am a big fan of the tv drama 'House'...does that qualify me to perform surgery? having a 1/2 hour class to get a piece of paper is not the same as being qualified to work in this industry.

My class was a week long out of town course. I took it in 2000 and have been doing residential AC and light commercial up to now. I have little experience in refrigeration applications.

sounds to me like one of support springs (internal to the compressor) broke...but why? install your new compressor and it may happen again because you are not qualified to understand the intricacies of how it really works...not just understanding the basics.

that's why i'm asking.

adding service valves and filters changes the game a whole lot. this doesn't mean that it can't be done and still work, but how much extra refrigerant are you going to add VERSUS how much should you add? if you got in touch with Copeland tech support, they will not talk to you about your SYSTEM, they would only tell you about the model number of the compressor (which you seem to already know) and what capacitor it takes, etc. wherever you bought the compressor is who you need to talk to about technical support, however, i suspect they don't know jack about it anyway. the companies that represent and sell Copeland products (properly) in the Midwest wouldn't have sold it to you anyway....well, except for 1 very large and nationally known company. they would sell it to you, but they don't know jack about anything in this industry except how to take money from anyone.

Copeland made the system, not just the compressor. It's their model number on it, as I listed it above. The entire package was rebranded by a now defunct company. The filter has a chart for additional refrigerant to be added.

you need to call a reputable company in your area. it will be faster and cheaper...i know you think that it won't be cheaper, but in the long run, it will be.

good luck.

I *AM* the reputable company. I am incorporated, licensed, and insured. I cannot apply here as a professional until my post count reaches 15 or so.

Are all the people here like you? Abrasive and insulting with no provocation? I understand that you have to try to weed out the DIY, hacks, and other non-pros but I am not one of those.

[HVAC_Marc]

"I'm not an HVAC expert" I'm not going to dwell on that as Jayguy has already done this. While we are mentioning TV shows, how about contacting the guys at "Tanked" on the Animal Planet channel. As they have unique solutions to aquarium related problems. Do you know what tank temperature you are supposed maintain. You are trying to move a lot of water through a relatively small heat exchanger. You did not mention the length of your 3/8 diam. tubing, but 9.6 gpm sounds a bit on the high side your velocity of flow is way to fast, about 20' per second. That doesn't give you a lot of time to cool the water, salinity or plain water.-GEO

No, I'm not a *refrigeration* expert. There's a huge difference. I'm not asking anyone to teach me so I can expand my business. I really don't want to do commercial refrigeration. So why do I do this one? It's for family.

Tank temperature to be maintained is 76 degrees. I don't know the length of the titanium exchanger as the PVC enclosure cannot be opened.

It's very similar to this 1/4 HP unit:

http://www.marineandreef.com/1_4_hp_...ller_s/201.htm

Pump size is 290-660 gallons per hour.

[HVAC_Marc]

I was thinking the exact same thing. Could be why his delta T is so low. The OP has got enough water flow for almost 4 tons of cooling.

We have to remember here, too, that livestock is involved that is not used to a flush of cold water. The Delta T needs to be low... cooling has to be gradual.

[wolfdog]

If you had started out with this little piece of information and your hat in your hand, you would have more success here.
Calling out some of the most informed and helpful people is not going to help you get information you are looking for.
Just my 2 cents

I *AM* the reputable company. I am incorporated, licensed, and insured. I cannot apply here as a professional until my post count reaches 15 or so.

Are all the people here like you? Abrasive and insulting with no provocation? I understand that you have to try to weed out the DIY, hacks, and other non-pros but I am not one of those.

[ga1279]

Since I managed to PO the OP I will back off and refrain from any further assistance, good luck to all and be safe. -GEO

[jayguy]

No, I'm not a *refrigeration* expert. There's a huge difference...

there isn't a huge difference...maybe a very small difference...maybe not even that big. in our industry, we use the properties of refrigerant (vapor compression) exactly the same in 'high temp' applications as we do in 'chillers' as we do in 'low temp' applications.

Since I managed to PO the OP I will back off and refrain from any further assistance, good luck to all and be safe. -GEO

good advice.

[jayguy]

...Are all the people here like you? Abrasive and insulting with no provocation?...

oh, i forgot to mention this gem...

no. not all people here are like me. some are worse. some are better.

[HVAC_Marc]

If you had started out with this little piece of information and your hat in your hand, you would have more success here.
Calling out some of the most informed and helpful people is not going to help you get information you are looking for.
Just my 2 cents

I did what the forum instructions told me to do. Put it in my profile. Also per the instructions I cannot post in the pro's forum until the post count is above 15 and it may take weeks for approval even with the proper submitted documentation.

[wolfdog]

I wouldn't want to disillusion you, but few people read the profile right away.

Back up, make peace, and try again. You got off on the wrong foot....maybe. Or you tripped and broke your ankle.
It's up to you.

[CCSPIERCE]

I would use the basics to determine your operation. If the compressor was knocking then debris is a possibility, to me, a drier makes sense. After evacuation add back your recovered amount plus the required amount to compensate for the drier. (use drier mfg. chart).
At that point in restart use the basics. Condensor entering and leaving to determine heat rejection. Calculate subcooling in the condensor to insure liquid feeding. Entering and leaving of the evaporater along with suction superheat. Finally be sure your compressor voltage and amperage readings are in line. After all that, then maybe you can experiment with water rate flows and see what happens. Even though it is a cap tube system you might want to consider a sight glass after the liquid line drier.

[HVAC_Marc]

I wouldn't want to disillusion you, but few people read the profile right away.

Back up, make peace, and try again. You got off on the wrong foot....maybe. Or you tripped and broke your ankle.
It's up to you.

I followed the rules. Can't help it if others don't or are too lazy to read a profile. This forum isn't my first rodeo, to use an old adage. It *is* the first one where the first reply post is an attack with no bearing.

I would use the basics to determine your operation. If the compressor was knocking then debris is a possibility, to me, a drier makes sense. After evacuation add back your recovered amount plus the required amount to compensate for the drier. (use drier mfg. chart).
At that point in restart use the basics. Condensor entering and leaving to determine heat rejection. Calculate subcooling in the condensor to insure liquid feeding. Entering and leaving of the evaporater along with suction superheat. Finally be sure your compressor voltage and amperage readings are in line. After all that, then maybe you can experiment with water rate flows and see what happens. Even though it is a cap tube system you might want to consider a sight glass after the liquid line drier.

Thank you, good person. So I should use the specs provided from Copeland about "5 degree F subcooling and 65 degree F return gas temperature" ? If I have these numbers will that positively insure that there is enough oil and refrigerant return for proper operation of the unit? I'm probably over-thinking the whole thing since I have no reference for what a small chiller total charge should be.

I think the failure was probably due to the number of daily cycles over 13 years. Probably 6-10 times a day. I do have some numbers as you have stated - the drier chart, subcooling, the superheat is easy enough, and the compressor voltage/amperage. I hadn't thought about a sight glass. That would definitely give a rough estimate of saturation.

My supplier in this area is United Refrigeration. I will get with them on Monday to look into that part. Fitting all the extras into the small case will be another story. Though, other varieties of this same system came with valves, sight glasses, and accumulators. It all depended upon the Bill of Material number (BOM) in the model code. Mine was 102 = no nothing.

[Tommy knocker]

I would say yes. You made it more complicated then it is, rite now. It was working fine except for the comp noise. You have the same comp to replace it so replace it. As far as the charge you weighed out, don't forget it's not all in that tank. The recovery machine and hoses still have some too. Put the comp, valves, and drier in. Pull a good vacume. Through 10 oz in it, start it up and adjust from there. If it can't get rite from there come back with good data and we can start throwing ideas at it. Good luck.

[HVAC_Marc]

I would say yes. You made it more complicated then it is, rite now. It was working fine except for the comp noise. You have the same comp to replace it so replace it. As far as the charge you weighed out, don't forget it's not all in that tank. The recovery machine and hoses still have some too. Put the comp, valves, and drier in. Pull a good vacume. Through 10 oz in it, start it up and adjust from there. If it can't get rite from there come back with good data and we can start throwing ideas at it. Good luck.

Thank you. Right now I have a holding charge installed. I want to make sure that everything is solid before I invest more time and another's money into it. It's probably paranoia, but it won't hurt. And, being cold here, the chiller isn't a huge rush.

[klove]

Service valves on a 1/4 HP compressor seem like a waste of money and time. Tommy gave good advice (the 10 oz part is a little subjective, but who knows?). The 65° return gas temp is a Copeland rating to ensure proper motor cooling on a suction gas cooled compressor. It's the upper end, not a number to shoot for as a normal course of action. If, as someone stated, it is a cap tube system, then trying to charge by subcooling is going to be like peein' up a rope........

[HVAC_Marc]

The "who knows" part is what worries me. Everything else is basic practice and replacement as in any other system.

Good to know about the 65 degree rating. After the beat down of the first few posts I was a little leery to ask for a clarification.

Yes, it's definitely a single capillary tube. After the vapor is condensed it flows out the coil (1/4") and into a small bulb (about 3/4" in diameter and 2" long). The bulb exits as 1/4" and reduces to cap tube size then wraps a number of times around the bulb before terminating at the 3/8" start of the titanium exchanger.

[HVAC_Marc]