Step past Step RefrigerantRecovery Procedure

I oftentimes meet new techs asking how to recover or experienced techs asking how to recover faster, so permit's accept a look at both.  If looking to connect with a potent civilisation of HVAC technicians, cheque out the subscription-based HVAC Know Information technology All app.

This all originated from some personal trial and error when an air conditioning manufacturer I worked for had a retrieve, a missing Schrader core at the receiver service valve (king valve) of all things.  This was a possible disaster for an unsuspecting tech. Remove the cap expecting a valve core, and well... Not fun.  So it was fourth dimension to install a single valve core in 50 operational units in critical spaces, each holding betwixt fifty and 100 pounds of R-410A.

I had a reasonably repeatable situation on my easily, and I had the opportunity to try all sorts of things: recovery cylinder size, hose size, hose blazon, etc.  I'll cover all this at the lesser of this article, but we've got to start with the basics!

How do we recover?

There are two typical methods, directly recovery and button/pull.  You should always familiarize yourself with the equipment you are working with, but I've included a elementary diagram of how to connect the required equipment and a "footstep-by-stride" guide for the newer techs.

Direct Recovery

This is our typical recovery method, which volition be how every recovery task will finish.

1.    Start with all valves closed (recovery cylinder, recovery machine, manifold,  hoses.)

2.    Setup hoses every bit shown in the diagram.

three.    Zip/TARE the refrigerant scale.

4.    Open hose valves, cadre removal tool valves or service valves.

i.    ---The below steps volition vary with your recovery machine---

5.    Ready the refrigerant recovery car to recover.

6.    Open the high side of the manifold for liquid recovery.

7.PURGE THE HOSES OF AIR, loosen and unseat the hose connected to the recovery tank until the refrigerant is present, then retighten.

8.    Fully open up the vapor valve on the recovery cylinder.

9.   Turn on the recovery machine.

2.    ---The below steps should be standard for well-nigh recovery machines---

10.    The manifold high side valve may need to exist adjusted to throttle refrigerant flow into the refrigerant recovery machine to avert liquid slugging.

11.    When the liquid recovery is complete, fully open both the high side and depression side manifold valves.

12.    Many recovery machines will turn off in one case the arrangement reaches a vacuum.

13.    PURGE THE RECOVERY Machine – this ane can exist pretty specific – and then cheque your manual if you lot're unsure.

14.    Close all valves and recovery is consummate!

Push/Pull

This will be your faster option if the system has 15 or more than pounds of refrigerant.  The more refrigerant the system holds, the more fourth dimension you'll save.  Tip: Using an inline sight glass during push button-pull recovery volition permit yous to visually decide when the liquid menses has stopped.

1.    Showtime with all valves closed (recovery cylinder, recovery machine, manifold, hoses.)

2.    Setup hoses as shown in the diagram.

3.    Cipher/TARE the refrigerant scale.

four.    Set the recovery motorcar to recover.

v.PURGE THE HOSES OF AIR (this is done slightly differently than in direct recovery.)
a.    Open up the liquid line service valve or core tool and then loosen and unseat the hose connected to the liquid port on the recovery tank until the refrigerant is nowadays and and then retighten.
b.    Open the vapor line service valve or core tool and and so loosen and unseat the hose connected to the vapor port on the recovery tank until the refrigerant is present and then retighten.

6.    Turn on the recovery auto.

7.    When liquid recovery is complete, switch to Direct Vapor Recovery.


Now, let's speed it up...

Valve Core Removal Tools

•    If you were only going to change 1 thing – this is information technology!  If you're stuck pulling through valve cores, become two of these.  They'll even help speed upwardly your evacuation.

RecoveryCylinder

•    Make certain the cylinder is clean and has been evacuated to 500 microns or less.  And NEVER fill up beyond eighty%. This allows for the expansion of the refrigerant.
•    If it's applied, use a larger cylinder; this volition make the recovery get quicker.

Hoses

•    Avert hoses with "anti-blowback" or "low loss" manner fittings.
•    Standard hoses are ¼" – using larger bore hoses will become you faster recovery. They're often marketed as "heavy duty," "charging," or "vacuum" hoses.
•    Utilise hoses that are as short as possible.

Temperature

•    Cool downwards the recovery cylinder– this will drib the pressure of the recovery cylinder.
•    With many recovery machines, yous tin can use the fan to draw air over the recovery tank.
•    Water volition work even improve, but you'll need water menstruation.

•    Absurd downward the refrigerant!  This 1 tends to be your all-time bet if y'all're dealing with big volumes of refrigerant – in that location are heat exchangers bachelor for just for this purpose.

FilterIt!

•    If you suspect the organisation refrigerant to be dirty, use an inline filter drier at the inlet to the recovery machine.

With methods ranging from nothing new required to a whole new rig for recovery, you've got choices to speed upward your recovery in only about all applications.  Give some of these a try and see how they work for you.

Dan Reggi

Humber College Professor

Follow HVAC Know Information technology All on Instagram, Facebook, YouTube and LinkedIn and LISTEN to the HVAC Know Information technology All Podcast

Save 8% on purchases at TruTech Tools with code knowitall (excluding Fluke and Flir products)