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Discussion Starter · #1 ·
Why do some manufactures insist on factory installing a LL dryer inside their condenser units?
Is this an attempt to make installation easier for DIY or are they truly concerned that a competent installer would somehow forget to actually use one. Seems silly to me.
Would you ever really consider not using a LL dryer on one of your installs?
 

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Tired & Drity
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Have ran into a few with 2, one factory installed in cabinet, 1 outside tech installed. double the fun I guess :blink:
 

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Lennox's policy as told to us in a class was to install a second drier for all low side repairs where gas can be pumped back into the CU. (R410a).

Remove the factory drier and stub to space with high side repairs, or if system is flat. Add drier outside of cabinet. Again we are are talking about R-410a systems.
 

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You really should not need a dryer other than the factory installed one if the system is clean and dry. It is just another restriction in the curcuit.
I was once told even in a compressor burn out situation you may need to change the dryer out a couple of times but once the system is cleaned up and no more acid to remove the dryer. Although I would still leave the factory dryer in place.
 

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You really should not need a dryer other than the factory installed one if the system is clean and dry. It is just another restriction in the curcuit.
I was once told even in a compressor burn out situation you may need to change the dryer out a couple of times but once the system is cleaned up and no more acid to remove the dryer. Although I would still leave the factory dryer in place.
ICP, Nordyne and many more do not come with driers. To say they are just another restriction is ignorance. All driers are much larger than the pipe they being installed on..
 

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Probably 80% plus of all units installed wouldn't have a LLFD if the factory didn't install one.

By installing one themselves. They reduce compressor failures. From those companies/installers that would be too cheap and or lazy to install one themselves.
 

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The only mfg who installs a LLD of significant size even worth mentioning

Armstrong. And maybe ICP. But the rest of them are tool small to make it worth while for my money.


I don't use equipment with the undersized LLD, but if we did we would put a 16cu in right at the evap as a routine matter.
 

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You really should not need a dryer other than the factory installed one if the system is clean and dry. It is just another restriction in the curcuit.
I was once told even in a compressor burn out situation you may need to change the dryer out a couple of times but once the system is cleaned up and no more acid to remove the dryer. Although I would still leave the factory dryer in place.
I would never leave any drier in place that was in the system prior to a burnout, that's just asking for problems.
 

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The only mfg who installs a LLD of significant size even worth mentioning

Armstrong. And maybe ICP. But the rest of them are tool small to make it worth while for my money.


I don't use equipment with the undersized LLD, but if we did we would put a 16cu in right at the evap as a routine matter.
Are you talking just residential condensing units or RTUs as well? I see plenty of Trane and other RTUs with full size filter driers all the time.
 

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Discussion Starter · #17 ·
Probably 80% plus of all units installed wouldn't have a LLFD if the factory didn't install one.

By installing one themselves. They reduce compressor failures. From those companies/installers that would be too cheap and or lazy to install one themselves.
I find this alarming. It’s disturbing to know that there are so many hack installers out there with no skills or conscience.
 

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I find this alarming. It’s disturbing to know that there are so many hack installers out there with no skills or conscience.
Lots of companies cut corners where ever they can. To make up for their low bids.

Lots of companies don't provide service agreements. And then get to make more money coming out to make repairs a few years later that they get to charge for. Because the unit held up long enough to make it through the labor warranty.

Compressor manufacturers are demanding that the FDs be installed at the factory in order to get the longer warranty.
Because they have seen the failures from poor install practices.

Many low priced companies, can't afford to send their techs to training classes. So those techs don't learn proper practices.
And end up walking around saying" I never heard of that".
 

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When I was a Regional Technical Service Manager for Gooman Manufacturing I constantly fought the internally installed filter/drier, to no avail. When Goodman started putting the filter/drier in the Amana brand units as well, I knew it was a lost cause to keep them out. Turns out that in order to get a better warranty from Copeland, Copeland required the units to have an internal F/D installed.

When you think about the massive amounts of units that are installed by piece workers in track homes and multi-family buildings it becomes easier to understand that most filter/driers provided with units never get installed.

I am with Lennox on their proceedure for filter/driers when work is done on sytems that requires opening up the refrigerant system. Other then poor installation practices, the most contaminants that get into systems get there from gauge hoses not being purged properly.
 
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