High pressure trip w/ low charge

[KB Cool]

Well, I had this alarm. I called for explaination.

The official reason that all those symptons will flag a High Head alarm, "..we're computer programers...picked the five conditions and chose what we thought would be the most common....."......"essentially the compressor is running outside it's design envelope".
Hope that helps. Hahaha

I'm thinking the 650 psi cut out switch flags the alarm!!!No? (transducer)I don't know. If it does it again and that massive filter dryer that i put in isn't clogged. I'm changing the HP switch!!! I've seen a few go bad on RTU's!

[Carrene #2]

I'm thinking the 650 psi cut out switch flags the alarm!!!No? (transducer)I don't know. If it does it again and that massive filter dryer that i put in isn't clogged. I'm changing the HP switch!!! I've seen a few go bad on RTU's!

My problem turned out to be low evap flow. Quite simple actually, just got to check things that would cause the compressor to run, "outside it's design envelope". Hehehe.

Reread your reply, not sure if you understood my post. There's a reason my handle is Carrene and a reason I posted, "official".

Good luck.

[KB Cool]

And whats up with the digital scroll? This peice of SH!t starts unloading every 7 seconds or so and loads again as i get to set-point! It can't be good for it!

[Dallas Duster]

Just because it says it digital is kinda misleading. It wouldn't be good for it if it unloaded more than 7 seconds. It works thou.

And whats up with the digital scroll? This peice of SH!t starts unloading every 7 seconds or so and loads again as i get to set-point! It can't be good for it!

[Carrene #2]

Unloading a compressor, not good. Go figure.
I think ya could stand to do some reading.
The "POS" compressor is usually misapplied, maintained by someone without the proper knowledge, or something else wrong with the system has caused the failure. Figure it out, that's our job.

[Carrene #2]

And whats up with the digital scroll? This peice of SH!t starts unloading every 7 seconds or so and loads again as i get to set-point! It can't be good for it!

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.

[KB Cool]

Unloading a compressor, not good. Go figure.
I think ya could stand to do some reading.
The "POS" compressor is usually misapplied, maintained by someone without the proper knowledge, or something else wrong with the system has caused the failure. Figure it out, that's our job.

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!

[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.