Test time for Pros and DIYer...

2570 Views 15 Replies 5 Participants Last post by hvaclover, Apr 8, 2009

hvaclover

Discussion Starter · Apr 8, 2009

Ques: Evacuation to well below 200 microns is:

A] Desirable and even even mandatory to remove all moisture.

B]The lowest level system should be pumped down to because ..(describe the changes that would be detrimental to the sealed system)

C] What is an evacuation?:huh:

Winner gets a No-Prize.

1 - 16 of 16 Posts

micromind

· #2 · Apr 8, 2009

It's been a while since I've actually done refrigeration work, but if the system isn't brought to a sufficient vacuum, it won't boil all the water out, and some non-condensible gasses will be left in.

I'll go with 'A'. 200 microns sounds familiar, but I could be way off.

I don't think a closed system could be pulled into enough of a vacuum to cause damage, in fact, it must be pulled into a pretty deep vacuum before it can be charged with refrigerant.

Leaving water and other icky stuff in it will dramatically shorten its life.

Rob

beenthere

· #3 · Apr 8, 2009

You could of made it a tough question.

hvaclover

Discussion Starter · #4 · Apr 8, 2009

beenthere said:
You could of made it a tough question.

Sarcasm from the Master:laughing:?

Give us your slant then, Been.

kenmac

· #5 · Apr 8, 2009

shouldn't C be , re-claim, re- cycle ???

I could be wrong but,
I thought evacuate was when you took all the refrigerant of someone's unit, took it home re- cycled it & put it in someone elses unit:yes: or, is that re- claim ? O' well who cares as long as it's cooling when you leave:laughing:

beenthere

· #6 · Apr 8, 2009

B.

The older mineral oils had wax/parrafin that could be separated.
Its not a worry with new mineral oil anymore.

Newer mineral oil, isn't effected until about 50 microns.

There was a big thread about this 6 or more months ago, at that other place.

I think Roby from National Refrigerants also participated in it.

As you probably know. He is a very open and straight forward guy, about myth and fact for refrigerants and oils.

Sort of like Andy Schoen for TXVs.

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hvaclover

Discussion Starter · #7 · Apr 8, 2009

I'll give it to you but the source i got it from is my latest SAM supplement and it says to exceed 200microns. So as long as you don't bust 200 your ok.

beenthere

· #8 · Apr 8, 2009

Doesn't suprize me.
Lot of resources will play it safe.

Hard to know, what oil that 8 year old unit has in it.
is it safe for 100 microns. or is it older oil, and not safe below 200 microns.

Most manufacturers, are still only recomending 500 to 400 microns for R410A systems.

York still sys to replace the line set when going from R22 to R410A.
Carrier says, just flush with Nitrogen.

In the field, it comes down to best practice and common sense for the job your on.

PS: Did you see the discussion about vacuuming water from underneath oil.

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hvaclover

Discussion Starter · #9 · Apr 8, 2009

beenthere said:
Doesn't suprize me.
Lot of resources will play it safe.

Hard to know, what oil that 8 year old unit has in it.
is it safe for 100 microns. or is it older oil, and not safe below 200 microns.

Most manufacturers, are still only recomending 500 to 400 microns for R410A systems.

York still sys to replace the line set when going from R22 to R410A.
Carrier says, just flush with Nitrogen.

In the field, it comes down to best practice and common sense for the job your on.

PS: Did you see the discussion about vacuuming water from underneath oil.

Nope didn't catch that. But your other points explain why there is such a regional difference in service practices.

Carrier made the new with their nitro purge article.

Be real interesting to see how all this new service techniques become bastardized over the coming years.

beenthere

· #10 · Apr 8, 2009

The guy in Florida. (you know who I mean)

They been doing nitro purges since 99 or so. And haven't had a failure of any type linked to purging instead of using a checmical flush.

Funny thing is.
In refrigeration. We been using POE oil since the early 90s(before anyone heard of R410A).

Only time any real problem with a conversion. Is if the evap was oil logged. Then the MO to POE mix is too much.

hvaclover

Discussion Starter · #11 · Apr 8, 2009 (Edited)

beenthere said:
The guy in Florida. (you know who I mean)

They been doing nitro purges since 99 or so. And haven't had a failure of any type linked to purging instead of using a checmical flush.

Funny thing is.
In refrigeration. We been using POE oil since the early 90s(before anyone heard of R410A).

Only time any real problem with a conversion. Is if the evap was oil logged. Then the MO to POE mix is too much.

AAHHhhh... the good old refer days. Got out of that end of hvac when an Arab store owner pulled a gun on me.:furious:.

His out side condenser suddenly and mysteriously :whistling2:disappeared that night.

I don't see any problem with a nitro purge and a good evacuation.

My first ac install was a Weatherking split made by Addison Products. Install instructions called for a back flush of liquid 22 for 15 seconds. Never lost a comp on any of em.

beenthere

· #12 · Apr 8, 2009

Westinghouse for me.

Purge and time metered the charge on them back in those days.

hvaclover

Discussion Starter · #13 · Apr 8, 2009

I still have this old Thermal products automatic charging gizmo. Thing belongs in a museum.

beenthere

· #14 · Apr 8, 2009

I use to carry a 5, and a 10 pound charging cylinder.
Until the mid 80's.

We use to sell R22 for 3 bucks a pound.

COLDIRON

· #15 · Apr 8, 2009

Weatherking

hvaclover said:
AAHHhhh... the good old refer days. Got out of that end of hvac when an Arab store owner pulled a gun on me.:furious:.

His out side condenser suddenly and mysteriously :whistling2:disappeared that night.

I don't see any problem with a nitro purge and a good evacuation.

My first ac install was a Weatherking split made by Addison Products. Install instructions called for a back flush of liquid 22 for 15 seconds. Never lost a comp on any of em.

I still have old Weatherkings 30 years old running. Efficiency, Oh well Reliability :thumbsup:. Liked the RCU unit with the suction accumulator.
Answer to A, B, C, does it have anything to do with a bathroom. I know 30 years go ahead and say it.

hvaclover

Discussion Starter · #16 · Apr 8, 2009

SULTINI said:
I still have old Weatherkings 30 years old running. Efficiency, Oh well Reliability :thumbsup:. Liked the RCU unit with the suction accumulator.
Answer to A, B, C, does it have anything to do with a bathroom. I know 30 years go ahead and say it.

That RCU was a nice looking unit for it's time.

All the units I installed look as good as the day they were installed.

Had HPCO and LPCO, accumulator, hi staring torque comp with a start ca[ and potential relay.

Still got sales literature on it. Damn thing never broke down.

1 - 16 of 16 Posts

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