High pressure trip w/ low charge

[KB Cool]

Unloading is certainly better than stopping and starting. Do you know of any other systems that unload, rather than starting and stopping ?

I'm beginning to understand how post counters rack up.

Maybe i'm used to the residential thing! The compressors stays unloaded in 1st stage and doesnt go to second every few seconds!!!

[Carrene #2]

Well lets hear it!!! You obviously work on them alot!!! I can honestly say! I don't!! SH to low causing floodback!!! Moisture because of POE!! Liquid off cycle migration due to no CCH!!!m I'm here to learn!

Funny thing is, I don't.
That's why I called Tech Support, looking for clarification on that particular alarm.

I do know how a refrigeration sytem works, I do know how a compressor works, I do know what's bad for a compressor.
Do you?

I have no idea what you know, so I'm not about to peck out over 30 years of experience, just so you might find your answer to the problem.

For your problem, as originally posted, if you understand the term of "compressor envelope" you will know where to look.

I hope.

[KB Cool]

Funny thing is, I don't.
That's why I called I called Tech Support.

I do know how a refrigeration sytem works, I do know how a compressor works, I do know what's bad for a compressor.
Do you?

Yeah, i know starting and stopping isn't good!!!

[Dallas Duster]

The reason it doesn't stay unloaded is for oil return . You could always tell the unit it's not digital and it will just cycle on and off.

Maybe i'm used to the residential thing! The compressors stays unloaded in 1st stage and doesnt go to second every few seconds!!!

[KB Cool]

The reason it doesn't stay unloaded is for oil return . You could always tell the unit it's not digital and it will just cycle on and off.

Thanks dallas!!! WHy didn't carrier just use 2 five ton scrolls and stage them!!! I could probally buy and replace a 5 ton 5 times for what this ten ton digital is going to cost!

[Carrene #2]

Thanks dallas!!! WHy didn't carrier just use 2 five ton scrolls and stage them!!! I could probally buy and replace a 5 ton 5 times for what this ten ton digital is going to cost!

Did you actually read my posts.
They did include "Misapplied". Hehehe.

[Dallas Duster]

Thanks dallas!!! WHy didn't carrier just use 2 five ton scrolls and stage them!!! I could probally buy and replace a 5 ton 5 times for what this ten ton digital is going to cost!

Size matters not sure there is enough room to stick 2 compressors in there for the foot print of the unit I agree with #2 sometimes chillers are oversized. Since most copeland tandems come as a complete unit cost cancels out. Dealing with smaller chillers like that most of the jobs are not professionally engineered it more of a rough guestimate.

[KB Cool]

Did you actually read my posts.
They did include "Misapplied". Hehehe.

Well, i do know these guys added a secondary loop and tried to run the machine through 1" pipe. It was short cycling like crazy.

[Carrene #2]

Well, i do know these guys added a secondary loop and tried to run the machine through 1" pipe. It was short cycling like crazy.

No Kidding.
Who commissioned it?

[KB Cool]

No Kidding.
Who commissioned it?

Nobody commisioned that!! They called and asked why it was turning off and on all the time!!!

[Carrene #2]

Nobody commisioned that!! They called and asked why it was turning off and on all the time!!!

Just got one like that! Misapplied!

[KB Cool]

Just got one like that! Misapplied!

Well, the customer knew they could not possibly run a 10 ten system on 1" pipe. But, they did think the unit was a true varible speed "digital" scroll and it would be ok ! Serious!!!

P.S. I just saw your edit a little bit ago!! I'll tell them to call you next time!!

[Carrene #2]

Well, the customer knew they could not possibly run a 10 ten system on 1" pipe. But, they did think the unit was a true varible speed "digital" scroll and it would be ok ! Serious!!!

P.S. I just saw your edit a little bit ago!! I'll tell them to call you next time!!

Thanks, but no thanks.

[chilbrig]

With the Micro coils the head will spike at startup then come back down to normal operating conditions. On a hot day it should not spike much over five hundred psig. If you must weigh in the charge subtact about five percent of what it says on the tag. If you overcharge just a little, it will trip. There should be a charging procedure in the OM book, that is the best way to charge it up. Again, if you have any restriction in the drier you will have problems.

[Dallas Duster]

He might be ok charging it up now since he added a small receiver to the system.

With the Micro coils the head will spike at startup then come back down to normal operating conditions. On a hot day it should not spike much over five hundred psig. If you must weigh in the charge subtact about five percent of what it says on the tag. If you overcharge just a little, it will trip. There should be a charging procedure in the OM book, that is the best way to charge it up. Again, if you have any restriction in the drier you will have problems.

[KB Cool]

With the Micro coils the head will spike at startup then come back down to normal operating conditions. On a hot day it should not spike much over five hundred psig. If you must weigh in the charge subtact about five percent of what it says on the tag. If you overcharge just a little, it will trip. There should be a charging procedure in the OM book, that is the best way to charge it up. Again, if you have any restriction in the drier you will have problems.

Yeah i blocked off the condensor to 120° CST and gave it 18° SC.

[KB Cool]

He might be ok charging it up now since he added a small receiver to the system.

I know i didn't want to add the dryer. Would have been much easier just to go back in w/ the 165s. But, my Boss talked the owner into doing the replacable core as thier maintenace men will be able to replace it on the fly as needed!!!

[KB Cool]

Thanks, but no thanks.

What a D!ck!!!




Nah, he aint a bad guy afterall!! Thanks for the 33% tip Carrene. Well definetly look into it if this compressor decides to lock up!!!

[Dallas Duster]

I guess the boss wins over common sense what is there a whopping 9 pounds or refrigerant in that machine.

I know i didn't want to add the dryer. Would have been much easier just to go back in w/ the 165s. But, my Boss talked the owner into doing the replacable core as thier maintenace men will be able to replace it on the fly as needed!!!

[KB Cool]

I guess the boss wins over common sense what is there a whopping 9 pounds or refrigerant in that machine.

8.6 lbs. There's about eleven in it now!!!!