AC compressor seized on 400 ISL

[Newcsn]

Came back from a 40 mile run this morning to smoke billowing out of the engine compartment. Looks like our AC compressor on our 2006 Dynasty w/ a 400 ISL has bit the dust - seized & burnt the belt off. I can’t find a part number on it anywhere, looked in the front cowling area and could not find a manufacture’s label & can’t seem to locate much info after doing several internet searches.

Also, what other components should I expect to replace when the compressor seizes? Orifice tubes (are there more than one), accumulator/drier, etc.

Thanks for passing along any insights!

[vito.a]

Monaco used Sanden A/C compressors that are for large trucks and buses.  The Sanden model will be on the Monaco build sheet.  

You'll need to see if any metal entered the A/C hoses.  Hopefully not but if so, they'll need cleaning out as well as the condenser.  The dryer is up front on the passenger side of the generator.  It will need replacing.  

Good luck!

[Dr4Film]

While replacing the compressor I would change out the expansion valve and the dryer.

I doubt that the compressor disintegrated throwing pieces into the AC lines versus simply seizing. Hence, the smoke was from the belt.

Once you find out what the replacement part numbers are for those three critical parts, please post them as I will have to replace all of them fairly soon myself.

[Newcsn]

@Dr4Film  & @vito.a Thanks for the feedback! Here’s hoping we don’t have metal in the system! I’ll be pulling the build sheet out in the next couple days & will definitely post part numbers as soon as I get them nailed down! Thanks again!

[Dr4Film]

My Data Card states that the engine AC Compressor is a Unicla model UP-150 serial#302331

I found an Internet reference that the Unicla UP-150 is the same as the Sanden SD7H15. I have not verified that information though.

The expansion valve is this one found on eBay I believe. https://www.ebay.com/itm/292153547690

However, there are many of the same type available for a lot less money. Whether they are the same quality or not I don't know. Just do an Internet search.

I haven''t been able to nail down the part number for the dryer. But they seem to be fairly standard.

I would think that when they evacuate the system it may remove any left over debris, not sure. I would ask the AC tech that will be replacing the parts. I am sure that their AC equipment is capable of flushing the system if needed.

BTW, when I needed a complete AC system for my 02 Windsor, I very nice customer service tech from ACParts.com in Texas helped me a lot in getting the correct parts, etc. I had a new compressor, expansion valve and dryer installed at a shop in LA when I had the new Samsung fridge installed back in 2012.

Edited February 15 by Dr4Film

[Paul J A]

6 hours ago, Dr4Film said:

My Data Card states that the engine AC Compressor is a Unicla model UP-150 serial#302331

I found an Internet reference that the Unicla UP-150 is the same as the Sanden SD7H15. I have not verified that information though.

The expansion valve is this one found on eBay I believe. https://www.ebay.com/itm/292153547690

However, there are many of the same type available for a lot less money. Whether they are the same quality or not I don't know. Just do an Internet search.

I haven''t been able to nail down the part number for the dryer. But they seem to be fairly standard.

I would think that when they evacuate the system it may remove any left over debris, not sure. I would ask the AC tech that will be replacing the parts. I am sure that their AC equipment is capable of flushing the system if needed.

BTW, when I needed a complete AC system for my 02 Windsor, I very nice customer service tech from ACParts.com in Texas helped me a lot in getting the correct parts, etc. I had a new compressor, expansion valve and dryer installed at a shop in LA when I had the new Samsung fridge installed back in 2012.

Yep. I'm sure Vito meant the Data Cards.

[beemerman]

Just a thought, it could be that the bearings on the pulley went bad and seized up the pulley.  Check the center of the pulley which is connected to the compressor to see if it will move.  You might just need a new clutch assy if you are lucky.

[Cevin Waffle]

I'm dealing with the same problem now. On my '08 Diplomat it uses the SCS Fridgette 094-00187. I have currently bypassed the compressor until I have time to change it. I did find that when I went to change out the belt that the fan hub bearing was worn letting the fan move back and forth a little. Figured this was a good time to change to the Source Engineering version and changed the belt tensioner as well. The fan change was a challenge but was worth it, considerable quieter. On my ISL400, I used a Gates 73", 8 rid belt to bypass the compressor.

[Jetjockey]

You unit is likely a rear radiator style and not side radiator? 

[Newcsn]

On 2/15/2024 at 6:33 AM, Dr4Film said:

My Data Card states that the engine AC Compressor is a Unicla model UP-150 serial#302331

I found an Internet reference that the Unicla UP-150 is the same as the Sanden SD7H15. I have not verified that information though.

The expansion valve is this one found on eBay I believe. https://www.ebay.com/itm/292153547690

However, there are many of the same type available for a lot less money. Whether they are the same quality or not I don't know. Just do an Internet search.

I haven''t been able to nail down the part number for the dryer. But they seem to be fairly standard.

I would think that when they evacuate the system it may remove any left over debris, not sure. I would ask the AC tech that will be replacing the parts. I am sure that their AC equipment is capable of flushing the system if needed.

BTW, when I needed a complete AC system for my 02 Windsor, I very nice customer service tech from ACParts.com in Texas helped me a lot in getting the correct parts, etc. I had a new compressor, expansion valve and dryer installed at a shop in LA when I had the new Samsung fridge installed back in 2012.

@Dr4Film Ditto - except for the serial number - my Data Card says Unicla UP-150. However, my compressor has a dual v-belt pulley not a serpentine. I believe I’ve located the Sanden SD7H15 series compressor w/ the appropriate pulley. Now I’ll have to figure out the dryer & expansion valve.

@Cevin Waffle Mine is a side radiator Dynasty w/ a separate v-belt for the AC compressor (thankfully). We may just use the rooftop AC until we get home and deal with it then.

[Jetjockey]

Whenever I change out an ac compressor I flush the whole system . Youwill be replacing several components and have it opened up anyway. It is hard to be certain whether or not metal got from the compressor into the system .  I flush the lines and disconnect the evaporator and condenser and flush them out.If it is not flushed out,the longevity of the compressor may be affected. It is also nice to flush out all the old oils to start with a nice clean system. If the compressor has ever been replaced before, you have no way of knowing if the system was flushed then . If not,it could be the reason for you current failure. Good luck

Edited February 17 by Jetjockey
Spell

[Jetjockey]

It was mentioned here that evacuation may remove debris.. not likely. A special flushing solvent is used to flush the system. Then blow clear with dry filtered air pressure. The evacuation process removes all the air and moisture from the system and if the vacc pump is a good one it will vaporize and vent residual oil if any. From there the pump is shut down under high vacuum. We let it sit for 24 hours and if it hold vacuum ,you can be confident the system is sealed. Some shops don’t flush or vacuum test. They just pump the system down and install prescribed amount of refrigerant. Than in a year or so when the compressor fails they gladly do it all over again. I have equipment that has run for over 20 years and still going fine. Fun fun.

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[Newcsn]

@Jetjockey Thanks for your replies & your thoroughness explaining the proper process of repairing, cleaning & recharging! It's been a couple decades or more since being a GM Master Tech & having to mess with automotive AC systems. So good to have a refresher!!!!

I have no problem with the replacement of the necessary components - that will be a bit like riding a bike. I will need to locate someone that can clean, pull down & recharge the system.

The journey continues!

Thanks again!

[Jetjockey]

Some oreilly or other parts stores may have the items you need. They should have flushing solvent. The flusher may look like a body paint gun.you put solvent in the can then it has a rubber tip like an air gun.. blow solvent til it is clear then blow with  filtered air til lines come dry . Do same with evaporator and condesor..I would replace all orings with ac type.. reassemble everything including compressor. Make sure the prescribe amount of oil is in the compressor, I usually add a couple ounces directly into compressor..This should close system.

Hook vacuum pump to gauges . Vacuum til you get vacuum close to current atmospheric pressure. this will ensure you have a sealed system and evacuate any moisture it contains.Close gauages  to trap vacuum. If in 8 hours or more,watch to make certain the system holds its vacuum. If it does not drift down more than 1 psi you have a sealed system. The 134 can be added thru the low pressure side of gauges  or high side without running compressor. It will draw til the can is empty,then add the remaining  134 prescribed. Don’t overfill as that will make the system less effective. When you run the system,check high and low pressure against a chart to see where pressures should be at your current ambient  temperature.

When you run the system the low pressure line at the compressor should become cold or even frost up if humidity is high enough.I love a frosty low pressure line ..  IIt will be the larger of the two lines .the smaller one is high pressure from compressor to evaporator.  I am.guessing you know all of this .if I left anything out or incorrect please correct me.
 

Sorry this is way to long!

Edited February 25 by Jetjockey