McQuay RRU134 Installation Manual

Installation, Operation & Maintenance Manual

Refrigerant Recovery Unit, Model RRU134

IOMM RRU134

Group: Refrigerant
Effective: December 2000

Supersedes: New

© 1999 McQuay International

Table of Contents

Specifications...........................................................................................................................3

Product Description.................................................................................................................4

Procedures for Liquid Push Pull Method...............................................................................5

Refrigerant Clearing Procedures...........................................................................................7

Changing Compressor Oil.......................................................................................................8

Electrical Parts Breakdown..................................................................................................11

Replacement Parts List........................................................................................................13

Troubleshooting.....................................................................................................................14

"McQuay" is a registered trademark of McQuay International

"Illustrations cover the general appearance of McQuay International products at the time of publication and we reserve the right to make

changes in design and construction at anytime without notice."

2 IOMM RRU134



1997 McQuay International

Specifications

Electrical Power Requirements

Recovery Main Components and Controls

115 Vac, 50/60 Hz, 1-Phase, 20-Amps

Minimum Circuit Amp 17.5, Maximum Fuse 20 Amps

240Vac, 50/60Hz, 1-Phase, 15-Amps

Minimum Circuit Amp 10.0, Maximum Fuse 15 Amps

Dimensions (approximate): 19 in. high x 14 in. wide x 18 in. deep
Weight: 100-lbs. (130-lbs. shipping)

Furnished with RRU134

Two ½ in. Female Flare Unions
Two 0.73-Litre Disposable In-line Filter Driers
Cable for 80% Full Safety Switch

NOTICE

McQuay International urges that all HVAC servicers working on McQuay equipment or any

manufacturer’s products, make every effort to eliminate, if possible, or vigorously reduce the

emission of CFC, HCFC, and HFC refrigerants to the atmosphere resulting from installation,

operation, routine maintenance, or major service of this equipment. Always act in a

responsible manner to conserve refrigerants for continued use even when acceptable

alternatives are available. Conservation and emission reduction can be accomplished by

following recommended service and safety procedures.

WARNING

To avoid injury or death due to inhalation of, or skin exposure to refrigerant, closely follow

all safety procedures described in the Material Safety Data Sheet for the refrigerant and to

all labels on refrigerant containers. Certain procedures common to refrigeration system

service may expose personnel to liquid or vaporous refrigerant.

IOMM RRU134 3

Product Description

McQuay’s RRU134 recovery system provides the efficient and safe recovery of most positive­pressure refrigerants and blends.

The unit consists of a 1.5-hp open drive compressor, high capacity 700 cfm air-cooled condenser,
system pressure gauge, tank pressure gauge and a valving system consisting of three manually
operated 3-way valves. Unit connections are ½ in. male flare with isolation valves. After four hoses
are connected and purged or evacuated, the user simply turns three 3-way valves to the liquid mode
position, opens all lines at the system being recovered, purges lines and turns the RRU134 on. The
RRU134 starts recovery by letting refrigerant migrate from the A/C system to the recovery tank. It
then draws vapor off the recovery tank, heats it via compression, and injects it back into the A/C
system high side, thus creating a pressure differential for a push/pull liquid transfer.

Two onboard gauges display system pressure and recovery tank pressure. When liquid has finished
transferring and the sight glass on side of the RRU134 is clear of liquid refrigerant, the user turns all
three 3-way valves to vapor recovery mode, allowing the RRU134 to pull vapor from both sides of
the A/C system being recovered. The RRU134 compressor begins recovering vapor which is first
cleansed by an external filter drier. The discharged hot refrigerant gas is then condensed by the air­cooled condenser and sent to the recovery tank as a liquid.

Transfer stops when an internal pressure switch indicates that the A/C system is under a 15 in.
vacuum. If pressure should again rise above 0 psig, the RRU134 will restart to pull all remaining gas
from the A/C system.

Safe Operations and Tips

To ensure your safety as well as others, before attempting to recover an A/C or refrigeration system,
proper and thorough preparation must take place.

Make sure that you have a recovery cylinder with a minimum ½ in. male flare vapor port and a
minimum ½ in. male flare liquid port with ½ in. internal dip tube, or larger ports if possible. This tank or
series of tanks must be able to hold the entire refrigerant charge at 80 % full.

Reminder: Refrigerant full weight is 80% of water capacity weight determined as follows:
Maximum allowable gross weight = 80% of water capacity weight + cylinder tare weight.

In addition, a suitable scale should be used to weigh the refrigerant charge in case RRU134 needs to
be shut down to prevent overfilling the tanks. If a scale is not available, the tanks can be equipped at
time of purchase with a float switch that will deactivate the RRU134’s 120-VAC control circuit. All
RRU134 units come with safety float connection and cable.

Finally, the recovery cylinder or cylinders must be pulled into a 29 in. vacuum before recovery
commences. Failure to follow these above stated procedures will decrease the likelihood of the
RRU134 performing at its highest possible effectiveness.

Peak Performance

To get the highest performance from your RRU134 unit, we recommend that you connect to ½ in.
evaporator and ½ in. condenser ports on the A/C system and to recovery cylinders with ½ in. ports
and dip tubes whenever possible.

4 IOMM RRU134

Procedures for Liquid Push Pull Method

1. Turn the refrigeration or A/C system off; make sure that the system cannot restart.

2. Connect the 120-VAC power cord to the RRU134’s control box and a 120-VAC 1-phase

minimum 17.5 amp maximum 20-amp outlet.

3. Connect all refrigerant hoses, as shown in Figure 1. Connect two ½ in. hoses to the RRU134’S

recovery tank side liquid and vapor ports and to liquid and vapor ports on the recovery cylinder.
Connect the other two ½ in. hoses to ports on the A/C system or refrigeration unit evaporator
and condenser as well as on the RRU134 system liquid and vapor ports. At this time connect
safety float cable from the RRU134 to recovery tank or use a suitable scale. If a scale is to be
used instead of float safety cut out, the 80% full bypass switch will need to be set to the “on”
position for the RRU134 to run.

4. Turn all three 3-way valves on the RRU134 to LIQUID MODE.

5. Open vapor and liquid access valves on A/C system being recovered.

6. Next open system vapor and liquid hand valves on the RRU134 recovery unit.

7. Next open tank vapor and liquid valves on the RRU134 recovery unit.

8. Turn upper left hand three way valve to PURGE MODE.

9. Purge both refrigerant lines at recovery tank, then turn upper left hand three way valve back to

LIQUID MODE.

10. Next open vapor and liquid hand valves on the recovery tank.

11. Turn the RRU134 power switch on and the RRU134 will automatically start drawing vapor off

of recovery tank and forcing higher compressed gas back into the condenser of the A/C
system. Liquid push/pull is now in process.

12. Continue to monitor the liquid sight glass on side of the RRU134. Once all of the liquid has

been completely removed and you are absolutely sure that all of the liquid has been removed,
proceed to next section.

WARNING

It is absolutely imperative that all of the liquid has been removed before switching into the

vapor recovery mode. Failure to do so may result in liquid slugging to the compressor and

causing major damage to the compressor.

Vapor Recovery Method

13. Once liquid site glass is completely clear of all liquid, turn all three, 3-way valves to VAPOR

RECOVERY MODE as shown in Figure 1. The RRU134 will now recover all of the
remaining gas and vapor from both sides of the A/C system and pull entire system into a 15 in.
vacuum.

14. Once the A/C system has been completely recovered to a 15 in. vacuum, the RRU134 will shut

down and “recovery complete” light will illuminate. Should pressure in the the A/C system
again rise above 0 psig, the RRU134 will restart and pull A/C system back into a 15 in. vacuum.

15. When recovery is finished, close both condenser and evaporator isolation valves on the A/C

system as well as the system vapor and liquid isolation valves on the RRU134 recovery unit.
To clear remaining refrigerant from the recovery tank hoses and RRU134 recovery unit,
proceed to the REFRIGERANT CLEARING PROCEDURES on page 7.

IOMM RRU134 5

Figure 1, Liquid Push/Pull Mode and Vapor Mode

Note: There will still be a small, residual amount of refrigerant in the RRU134. This
amount must be removed if you want to change to a different type of refrigerant. An
explanation on how to remove this residual amount of refrigerant is explained in next
section.

6 IOMM RRU134

Refrigerant Clearing Procedures

1. Make sure that the A/C system side isolation valves are closed and that the recovery tank vapor

and liquid side isolation valves on the RRU134 and recovery tank are still open.

2. Turn the 3-way valve marked “hose clearing” to its hose clearing position. The RRU134 unit

will automatically restart.

3. Close the vapor valve on the recovery tank. Watch both the tank gauge and the system gauge

on the RRU134 unit. The system gauge will pull all the way to a 15 in. vacuum and shut the unit
down. Once the RRU134 shuts down, immediately close the liquid valve on the recovery tank.

4. Disconnect the tank vapor hose, then slowly disconnect the tank liquid hose. There will still be a

minute amount of refrigerant left in this hose. Purge off and unit will be ready for next recovery
job.

Note: After recovery is complete and all the refrigerant has been removed or purged from
the hoses, the RRU134 may still have a residual amount of refrigerant in the unit. To
remove this refrigerant, connect an evacuated recovery cylinder to the compressor suction
and discharge ¼ in. Schrader valves on the side of unit. Allow the remaining refrigerant to
be pulled into cylinder. This procedure needs to be performed whenever a different type of
refrigerant is to be recovered.

Changing Replaceable Cores

Make sure you replace the disposable filter driers after each recovery job. Simply remove the used
filter drier assembly and replace. Driers should be used on the system vapor and liquid inlet ports
located on the RRU134. Failure to use driers on each and every recovery may result in damage to
the recovery compressor.

IOMM RRU134 7

Changing Compressor Oil

The compressor’s charge of Polyol Ester oil should be regularly replaced with an identical fluid or, at
a minimum, after any of the following events:

1. After a maximum of 10 hours of run time.

2. When changing recovery jobs that involve different refrigerants.

3. After recovering a system with a burnt out compressor.

When changing oil, it is highly recommended that the same type of oil being used with the

refrigerant being recovered be used in the rru134 compressor. This will help ensure that

cross-contamination does not occur.

To remove and change the oil in the compressor and the oil separator:
a. Make sure that the RRU134 unit has no refrigerant in its internal parts.

b. Connect a manifold set to dry nitrogen and to the suction and discharge service ¼ in. access

ports located on the side of the RRU134.

c. Connect another ¼ in. hose to the access fitting on the bottom of the RRU134 oil separator

fitting and the other end to a suitable disposable oil container.

d. Gradually allow dry nitrogen to go into the discharge port on the RRU134 unit until all oil has

been forced out of the oil separator. Note : 10 to 15 psi will be more than adequate.

e. Connect another ¼ in. hose to the access fitting on the bottom of the RRU134 compressor fitting

and the other end to a suitable disposable oil container.

f. Gradually allow dry nitrogen to go into the suction port on the RRU134 unit until all oil has been

forced out of the compressor.

g. To add new oil to the RRU134 compressor, connect a vacuum pump to the ¼ in. access port on

the suction side of the compressor. Pull down into a minimum 29 in. vacuum.

h. Connect the other hose to the ¼ in. access port on the bottom of the compressor and into the

new oil container. Note : Fill compressor with exactly 14 oz. of oil.

i. After the compressor has been filled, connect the other hose to the ¼ in. access port on the

bottom of the oil separator and into the new oil container. Note : Fill oil separator with exactly 4
oz. of oil.

j. Once this procedure is finished, remove all hoses and pull entire RRU134 into a 29 in. vacuum.

Dispose of old oil properly.

WARNING

WARNING

Failure to follow the above procedures for recharging oil in compressor with the exact

amount of oil may result in major damage to the compressor.

8 IOMM RRU134

Figure 2, Process and Identification Schematic - Purge Mode

Figure 3, Process and Identification Schematic - Liquid Mode

IOMM RRU134 9

Figure 4, Process and Identification Schematic - Vapor Mode

Figure 5, Process and Identification Schematic - Hose Clearing Mode

10 IOMM RRU134

Electrical Parts Breakdown

1 Compressor Motor

1.5 HP, 120 VAC, 50/60 Hz, 1Ph 3450 RPM

2.0 HP, 240 VAC, 50/60 Hz, 1Ph 3450 RPM

2 Condenser Fan Motor

35W, 115V, 50/60 Hz

35W, 230V, 50/60 Hz
3 High Pressure Switch 350 Psig
4 Low Pressure Switch 15 Hg
5 Male Inlet - 20A, 125V, 2 P, 3W GRD

Male Inlet - 20A, 250V, 2 P, 3W GRD
6 Terminal Block
7 Yellow Indicating Lamps 120 VAC
8 Red Indicating Lamps 120 VAC OR 220 VAC
9 Power Switch 250 VAC

10 Circuit Breakers- 20 Amp, 250 VAC, 28 VDC
11 120 VAC Contactor or 240 VAC Contactor
12 Tank Safety Float Connector

IOMM RRU134 11

Figure 6, Electrical Block Wiring Diagram

B

CIRCUIT

G

BREAKER

W

HIGH PRESSURE

SWITCH

YELLOW VAPOR

LIGHT

ON OFF

SWITCH

RED 80%

TANK FULL LIGHT

LOW PRESSURE

SWITCH

R

R

2 354 6 7 8

1

B

B B W

TANK FLOAT

SWITCH

12 IOMM RRU134

Replacement Parts List

Reference Number Part Number Description

1..........................RCP001.................Vapor Recovery Compressor

2..........................EMO115.................Compressor Drive Motor

2.........................EMO315.................Compressor Drive Motor

3..........................RV-304..................3-Way Valves

4.........................XSW350................High Pressure Switch

5..........................RVA304.................Transfer Valves

6.........................EMO136.................Condenser Fan Motor

6.........................EMO035.................Condenser Fan Motor

7..........................RCC011.................Condenser Coil

8..........................MFR002.................Unit Frame

9.........................ROS001.................Vapor Comp Oil Separator

10.........................RVH004.................Hand Ball Valves Tank and System

11 .........................EMS002.................Contactor

11 .........................EMS003.................Contactor

12.........................ELT002.................Lamp Red

12.........................ELT003.................Lamp Red

13........................ESW002................Power Switch

14.........................RVC004.................Check Valve

15..........................EMI115..................Male Inlet 120V

15..........................EMI200..................Male Inlet 250V

16.........................RVC003.................Check Valve

17.........................HFB010.................Condenser Fan Blade

IOMM RRU134 13

Troubleshooting

To avoid injury or death due to inhalation of, or skin exposure to refrigerant, closely follow

all of the safety procedures described in the Material Safety Data Sheet for the refrigerant

and to all labels on refrigerant containers. Certain procedures common to refrigeration

system service may expose personnel to liquid or vaporous refrigerant.

Troubleshooting Procedures

If functional difficulties are experienced and the preceding maintenance checks do not resolve the
problem, refer to the following troubleshooting chart for assistance.

Troubleshooting Guide

The following guide is provided to assist in analyzing problems that could occur.

• Symptom: Describes what is happening;

• Cause: Suggests possible sources;

• Solution: Describes what must be done.

Symptom Cause Solution

Pressure differential between
system and recovery tank
becomes too high - greater
than 50 psig.

Slow liquid transfer. Restriction in flow. Replace restrictive fittings and hoses with appropriate

RRU134 running high head
pressure back to recovery
tank.

RRU134 compressor won’t
restart.

RRU134 slugging with liquid
during liquid push/pull.

WARNING

Restrictions in recovery line. Remove restriction in liquid recovery lines or tank.

Tank needs to have minimum ¼ in. ID valves and dip
tube.

size to expedite transfer.

Restriction in hoses going to
tank.

Capacity of recovery tank is
too small or tank is overfilled.

High concentration of
noncondensibles.

Condenser fan not working. Fix fan.
Compressor thermal overload

open.
High head pressure. Open bypass valve and close after restart.
Recovery hose incorrectly

connected. This may cause
liquid to be injected into
compressor.

Improper valves on recovery
tank allowing liquid to be
injected into compressor.

Replace with appropriately sized hoses and fittings.
Run water over tank or add secondary water cooled
condenser on liquid return line going to recovery tank.
(McQuay has available secondary water cooled and
air cooled condensers.)

Replace with appropriately sized tanks.

Remove noncondensibles.

Let unit cool down.

Verify that the system vapor and liquid lines are
properly connected and that the vapor and liquid lines
on recovery tank are connected correctly.

Verify that the liquid and vapor valves on the recovery
tank are separate and that the recovery tank is no
more than 80 % full.

14 IOMM RRU134

IOMM RRU134 15

Post Office Box 2510, Staunton, Virginia 24402-2510 • [phone] • www.mcquay.com