17EX/17FA R22

[poppop]

Anybody ever replace the drive end bearing on a 17FA R22 compressor? Can it be accessed through the bearing inspection cover or must the compressor end cover be removed?

[Ph-D]

The 17EX chiller is a relative new unit while the 17FA could be a very old unit and anywhere up to 10,000 tons. More details on the actual unit are required because some can have their bearing replaced throught the inspection access cover while others due to their size and weight (shaft) it is almost impossible. The unit frame size will dictate if you can or it would be more responsible to not take a chance and do complete compressor overhaul.

[poppop]

It's a single shaft 17FA R22 unit, meaning it's externally geared. Circa 1991.
Don't have model number in front of me, guessing approximately 1500 tons.

[Ph-D]

Your responds has me a little confused, if this compressor is externally driven with an external speed increaser as stated it will most likely be of the Carrier 17MA, PA or SA variety. This is a completely different can of worms.

[klove]

Now I'm confused - I thought all 17 series Carriers were open drive.

[nyrb]

As far as I know all the 17 series are open drive, which unit do you have, this one.

http://www.docs.hvacpartners.com/idc/groups/public/documents/techlit/17fa-4ss.pdf

Or this one?

http://www.docs.hvacpartners.com/idc/groups/public/documents/techlit/17ex-1ss.pdf

I'm got a 17S apart right now and the journal bearings are replaceable through the inspection covers but it's a completely different beast.

[poppop]

To clarify:
Yes all 17 series Carrier chillers are open drive. The original 17FA's had no speed increaser or gear box external to the compressor. The transmission was internal in the compressor shell. The later R22 compressors were of the single shaft variety, the speed increase done externally so only one shaft was found inside the compressor shell. That's the animal I've got. One shaft, no internal transmission. The drive end bearing is bad, concentricity way out. Do I need to pull the compressor end cover off or can I remove the drive end bearing through the inspection cover?
I was told this type of compressor was used on the 17EX, but I've never seen a 17EX so I can't vouch for the veracity of the statement.

[poppop]

Checked the pdf docs.
No clear picture in the 17FA SOM Manual, however the 17EX SOM is dead on.
The question is can the seal end journal bearing be replaced through the inspection cover?

[nyrb]

Look at page 2 and 7 of this link, it claims large inspection covers for ease of bearing inspection without compressor disassembly which I assume would also include replacement (in order to inspect the bearing you have to be able to remove it in my mind). The difficult part might be rigging a means of supporting the shaft or at least relieving some of the weight so you can spin out the bottom half of the split journal bearing. Take this as speculation on my part from looking at this compressor on paper only, I don't have this style at any of my sites and the 17 series I do work on have a split casing with journal bearings on both sides of the wheels, and those bearings are easily changed through the inspection covers.

http://www.xpedio.carrier.com/idc/groups/public/documents/techlit/17ex-1pd.pdf

[Ph-D]

Thanks for the education, it has been very interesting.

[poppop]

Thanks Nyrb. Looks like a do-able job. Any job can be done... it just needs to be done economically. Carrier Literature is so damned confusing as to the 17FA/17EX model differentiation. You pull up a parts catalogue or list for the 17FA and only the internally geared machines are listed.
Hopefully replacing the seal end bearing will bring our concentricity back to spec.

I'm grateful for your help and hope I can be of service to you soon.

[Carrene #2]

The one I did last week was an older model than the one you speak of, it had an internal tranny.
The drive end bearing was behind the seal and only the seal had to be removed to change the bearing.

[nyrb]

Hey Carrene, we haven't seen your face around A-burg in a while, I bet you miss it badly, Wayne says hi.

[Carrene #2]

Hey Carrene, we haven't seen your face around A-burg in a while, I bet you miss it badly, Wayne says hi.

Well, actually....... I do (other than living out of a suitcase). They always treated me good there.
Last time I saw Wayne, he passed me on the HWY and we pulled into a truck stop and had a visit.
He'll be packin' to head south, pretty soon. LOL

Sorry to get off topic.