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Crankcase Heaters not required - Goodman

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raulsteichen

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Discussion starter · #1 · (Edited)
So I'm reading this Goodman install manual for split systems: https://www.alpinehomeair.com/related/cprt%20install%20instructions.pdf

It says this:

"SCROLL COMPRESSORS The following should be read prior to installing units with scroll compressors...

Crankcase Heater

Scroll equipped units do not have nor do not require a crankcase heater."

Now I'll have to assume that the double negative "nor do not" is because of an illiterate staff at Goodman, and that they are actually saying that crankcase heaters are not required on Goodman splits with scrolls.

So, if that's the case, does anyone know why Goodman recommends not installing heaters on scrolls?

I came across a Goodman HP in MN today (30° F this morning) with no heater, and according to this manual that's the way it should be. I'm from FL, working a temp job up here, so I'm learning.
 
#3 ·
Most equipment will state "crankcase heater must be energized 24 hrs before startup". Then the next unit you look at from the same manufacture wont have any.

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#4 ·
Crankcase heaters are often not speced on those smaller units. Unless you have a line length over X number of feet and the charge exceeds X amount. Then they will require crankcase heaters. I'm thinking it's something about the ratio of refrigerant to oil, but I dont know that.


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Discussion starter · #5 ·
icy78 said:
Crankcase heaters are often not speced on those smaller units. Unless you have a line length over X number of feet and the charge exceeds X amount. Then they will require crankcase heaters. I'm thinking it's something about the ratio of refrigerant to oil, but I dont know that.
Click to expand...
This manual is for splits up to 5 tons, and includes tables for linesets up to 75'.
 
#7 ·
Scrolls have the capability to push refrigerant droplets through the plates without damage. That's what they claim anyways.
Does that mean the oil won't be deluted on start up ?
If yes then how will the bearings react ?
 
#8 ·
VTP99 said:
Scrolls have the capability to push refrigerant droplets through the plates without damage. That's what they claim anyways.
Does that mean the oil won't be deluted on start up ?
If it is then how does the bearings react ?
Click to expand...
Getting a rare flood back to the Scroll and getting those droplets thru the comp is one thing. A Scroll that is subjected to migration, heavy migration and still have the comp survive is a diff story. Depending on the Scroll MN# , some of the "newer" Scrolls have been re-tooled to have "extremely" small passages in between the comp crankcase and the "inlet" to the scroll. Due to the tightness of the avenues of travel for the freon/oil to get from the cc to the scroll,to cause damage, most of that frothing liquid is kept within the confines of the cc. Supposedly!
 
#10 ·
I was taught scrolls are hard to slug. But you can still easily wash out the top bearings with low SH and no CCH.

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#11 ·
A crankcase heater will not correct low superheat/ flood back though. The question from the op was why Goodman does not want or does not require crankcase heaters on these compressors. Emerson's application engineering bulletins require crankcase heaters on applications over a certain amount of charge . All low temp Scrolls get crankcase heaters.
I think Spitz was right partly also in that they're saving a couple of bucks by not putting them on and betting the compressor will outlast the warranty period.
It's probably not too much of a gamble though I mean they're not stupid and they do have a 10 year warranty on their compressor
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