R-22 to R-410A changeout

Servicewiz_3

Any helpful tips on this changeout?

pecmsg

A vague question!

Like for like
Insure the line set is the correct size
Blow out liquid and suction lines well with N2

Triple evacuations

HVACNUT

Meaning you're not able to replace the refrigerant lines?

Its 2020 and this is your first rodeo?

If you're certified but green, the book learning should be fresh in your head on how to properly recover, flush and prep.

pecmsg

Please NO Flush!

ChrisJ

pecmsg said:

Please NO Flush!

Some habits die hard.........

pecmsg

Why do you need to pour chemicals in the line set that can do more harm then good?

The few oz of mineral oil in there does nothing. We learned that in the 90's with R-134A conversations.

The biggest issue is the crap that returns to the compressor because of the cleaning ability of POE and bad install practices. A suction filter should be installed then removed in a few days of operation. Unfortunately they only get removed after there plugged!

ChrisJ

pecmsg said:

Why do you need to pour chemicals in the line set that can do more harm then good?

The few oz of mineral oil in there does nothing. We learned that in the 90's with R-134A conversations.

The biggest issue is the crap that returns to the compressor because of the cleaning ability of POE and bad install practices. A suction filter should be installed then removed in a few days of operation. Unfortunately they only get removed after there plugged!

Speaking of,
How do you get "tainted" POE out of a system? I.E. POE that's been exposed to a lot of moisture etc.

pecmsg

ChrisJ said:

pecmsg said:

Why do you need to pour chemicals in the line set that can do more harm then good?

The few oz of mineral oil in there does nothing. We learned that in the 90's with R-134A conversations.

The biggest issue is the crap that returns to the compressor because of the cleaning ability of POE and bad install practices. A suction filter should be installed then removed in a few days of operation. Unfortunately they only get removed after there plugged!

Speaking of,
How do you get "tainted" POE out of a system? I.E. POE that's been exposed to a lot of moisture etc.

Dump it and replace it. Even a 500 micron vacuum the moisture remains.

How are you getting enough to worry about?
First buy in smaller quantities.
Second use what you need. I put some N2 in the can before resealing but also get rid of the can if not reused within a month.

ChrisJ

> @pecmsg said:
> (Quote)
> Dump it and replace it. Even a 500 micron vacuum the moisture remains.
>
> How are you getting enough to worry about?
> First buy in smaller quantities.
> Second use what you need. I put some N2 in the can before resealing but also get rid of the can if not reused within a month.

I'm not, just something I've wondered about. If it's all throughout a system what can you do with it.

SuperTech

What about using a flush kit when replacing a compressor that had the windings burn out? Some guys insist that it's necessary. I like the idea of replacement of the suction and liquid line driers after a few days better myself.

pecmsg

ChrisJ said:

> @pecmsg said:

> (Quote)

> Dump it and replace it. Even a 500 micron vacuum the moisture remains.

>

> How are you getting enough to worry about?

> First buy in smaller quantities.

> Second use what you need. I put some N2 in the can before resealing but also get rid of the can if not reused within a month.



I'm not, just something I've wondered about. If it's all throughout a system what can you do with it.

Just change the oil once.

Moisture and POE is a concern but mostly from bad practices of leavening containers open. 3GS days.
As far as working on systems unless you actually blow into the tubing or its raining out and the suction is facing up and open its a non issue. Make your repair change the drier and close it up.