New compressor, shuts off on high head pressure

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1999Suburban
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Re: New compressor, shuts off on high head pressure

Post by 1999Suburban »

I will try misting the condenser to see if head pressure drops. If it is does, what does that indicate?

Yes, I am certain we flushed all solvent out of system; we drained the compressor several times and emptied it repeatedly blowing air through the system long after the exiting air was dry. Leaving any in was one of my concerns.

As for oil, I think it was 11oz? I ordered all parts from ackits.com and Tim told me how much to use. After removing what came in the compressor, we measured out the new oil and slowly poured it into the compressor, rotating it slowly until all of the oil went in. I forget what weight they were, but the required oil was different than what the compressor came with.
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Tim
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Re: New compressor, shuts off on high head pressure

Post by Tim »

Misting will lower the head pressure if you have an airflow issue like a bad clutch fan. I'm just mentioning a few things before you rip into the system.

Email the name it was billed under. So I can see what was sold.
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1999Suburban
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Re: New compressor, shuts off on high head pressure

Post by 1999Suburban »

Hi Tim,

I just replied to your email with my invoice.

Got it.

Pf Condenser, and some other goodies.
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Re: New compressor, shuts off on high head pressure

Post by JohnHere »

1999Suburban wrote: Fri Jul 07, 2023 11:15 am As for oil, I think it was 11oz?
That's the spec I have as well.
Member – MACS (Mobile Air Climate Systems Association)

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Tim
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Re: New compressor, shuts off on high head pressure

Post by Tim »

Yu have a new OT on your order. You can always reclaim the refrigerant and check if it has debris. If the condenser is plugged, the OT should show signs as well.
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tony1963
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Re: New compressor, shuts off on high head pressure

Post by tony1963 »

I don't know how you can build 425 lbs on the high side with 14/56 ounces of refrigerant in the system unless you have a restriction.

That charge represents only 25% of the system's capacity.
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Re: New compressor, shuts off on high head pressure

Post by Tim »

tony1963 wrote: Fri Jul 07, 2023 12:52 pm I don't know how you can build 425 lbs on the high side with 14/56 ounces of refrigerant in the system unless you have a restriction.

That charge represents only 25% of the system's capacity.
A PF condenser works in a series of tubes and drops down to the next set in a series, not one single tube running back and forth. A PF condenser could be 75% plugged and still have volume pass out the other end leading to my condenser being fine report. We need to know if there is debris present currently.
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1999Suburban
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Re: New compressor, shuts off on high head pressure

Post by 1999Suburban »

Really great and responsive forum, thank you everyone.

Tim, what is OT, orifice tube? When we pulled it out, it did have some shmootz on it, so we cleaned it and reinstalled it.

From these posts, it appears obvious I have a restriction. Since the new condenser is the only component I did not flush out or blow air through, that now seems like the best part to isolate and clean out. Would you all agree?

The condenser has a Schrader valve in about the middle on one side. I can hook up nitrogen or compressed air (I have both) and blow it out. Or I can blow through either/or both ends, or all three. Not sure how to measure output to know if any restriction is now moved, however, unless there is an obvious change in air flow.

Out of the condenser is a tee that is sort of Y shaped; splits into two, one for each evap. What are the chances this is where the restriction is located?

Anything else I should blow out and/or visually inspect before putting it all back together again?

Thank you again for the excellent guidance.
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Re: New compressor, shuts off on high head pressure

Post by tbirdtbird »

If you had contamination of the OT orifice tube then there is/was crap in the system.
And it really is not possible to flush a condenser because of the parallel paths
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Re: New compressor, shuts off on high head pressure

Post by Tim »

It would have been nice to have an image of the OT before you cleaned and reinstalled it. The system, IMO, was not cleaned enough before the new components were installed.

New Sanden compressor
New PF condenser
New Rear Valve
New accumulator

Yet debris was already present at the OT just minutes after installation. I would bet the rear still was full of junk and has just used your new PF condenser as a filtering device. Dual-unit systems are the hardest to get clean. Long runs and so much debris can be present.

Positive note, the compressor is probably okay. I would drain the oil and replace it. I would replace the condenser and accumulator and OT again. But before anything. I would break each component into individual sections and make 100% sure there is no debris present.

Flush and re-flush those components. When you think you have it clean, flush again.
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