EPA Type 3 Flashcards
The purpose of the purge unit on a low pressure chiller is to
Remove non condensable gases from the top of the condenser
The rupture disc of a low pressure chiller is connected to the
Low side
What is the maximum pressure to which one should pressurize an r11 chiller in order to leak test it
10psig
What must be done to the oil in a chiller sump before removing it
Must be heated to 130* to drive out any refrigerant
An r11 centrifugal chiller is charged through the valve located at the
Bottom of the evaporator barrel
300 ton, r123 chiller supplying chilled water for conditioning a library must be repaired if it leaks at a rate of more than __ annually
15%
A 1,000 ton, low pressure chiller used to cool water must not be allowed to leak refrigerant at a rate greater than __ of its total charge annually without being repaired
35%
Low side pressure in a r11 chiller which is providing 45*F chilled water for a/c would be
16” hg
When disposing of a r123 chiller, the refrigerant must be removed down to a pressure of __ before being dismantled
29” hg
If the oil sump in a centrifugal chiller is not heated during refrigerant recovery, what can be the result
After required recovery is reached, system pressure may rise again
How are water tube leaks found in low pressure chillers
Hydrostatic tube test
Reward for providing information leading to the conviction of someone violating section 608of the clean air act can be as much as
$10,000 per day per violation
What can happen to a low pressure chillers evaporator tubes if water is allowed to stand in them during refrigerant recovery
The water can freeze
If a recovery machine is being used to pressurize a system to recover liquid refrigerant, what can happen if it discharges at a pressure greater than 15psig
It can burst the rupture disc on the chiller
The discharge from a purge unit should be piped where
Outdoors
Excessive purging from a chiller purge system can be an indication of
Non condensable gases leaking into the chiller
Using a controlled hot water pressurization system to raise the chillers pressure to atmospheric in order to replace a non major component of the chiller is
Allowed
Which refrigerant is an interim, retrofit replacement for r11in low pressure chillers
R123
After recovering just the liquid refrigerant from a 350 ton r11 chiller how much refrigerant would still be in the system in vapor form
About 100 lbs
R123 is classified by ASHRAE as a __ refrigerant with regard to its toxicity and flammability
B1
How should one remove frost from the sight glass of a chiller
Spray alcohol on it
Recovery machines used for low pressure systems will use what water source to cool their internal condensers
Local water supply
The preferred method for pressurizing a low pressure chiller for leak testing would be to
Use a controlled heated water system to warm the chiller up
Because a low pressure system operates below atmospheric pressure, leaks in the
Gaskets or fittings will cause air and moisture to enter the system
When charging a system with a low pressure, refrigerant should be introduced as a vapor to raise saturation temperature to a minimum of
36*
EPA required evacuation levels for recovery of recycling equipment manufactured or imported on or after Nov. 15, 93 is
25mm hg absolute
If a strong odor is detected during the recovery process
A compressor burn out may have occurred
A low pressure chiller used for comfort cooling must be repaired if it has an annual leak rate of __ of the total charge
15%
A rupture disc for a low pressure chiller will rupture at
15psig
What refrigerant has a safety classification of B1
R123
When installing more than one, pressure relief valves must be installed
In parallel
When pressurizing a system do not exceed
10psig
ASHRAE 34 standard safety classifies r134a as
A1
After reaching the required vacuum on an appliance when servicing, moisture is indicated by
Multiple rises in pressure with an increase of pauses between rises
In a chiller, air and other non condensable collect
At the top section of the condenser
Who establishes the refrigerant safety group standard
ASHRAE
What type of equipment can be worked on with type 3 certification
Low pressure
To repair a chiller operating with r22 a technician must have a
Type 2 certification
The owner must keep records of refrigerant added during service and maintenance on equipment with charges of __
50lbs or greater
After all the liquid has been removed from an average 350 ton approximately how much vapor refrigerant remains in the system
100lbs
Where is the purge unit located in a low pressure system
The top of the condenser
When leak testing a low pressure chiller, the max pressure to use is
10psig
During evacuation of systems with large amounts of water, it may be necessary to
Increase pressure by introducing nitrogen to counteract freezing
What can be used to pressurize a chiller system before opening the system for a non major repair
Controlled hot water
Refrigerant recovery from a system using r11 or r123 starts with
Liquid removal followed by vapor recovery
The standard for machine room safety is
ASHRAE standard 15
The most efficient method of leak checking a charged low pressure refrigeration unit is to
Pressurize the system by the use of controlled hot water or heater blankets
EPA required evacuation levels for recovery or recycling equipment manufactured or imported before Nov. 15, 93 is
25” hg
In an equipment room containing a r123 chiller a refrigerant specific sensor must be used to warn of leaks
True
When recharging an evacuated chiller with r11, vapor must first be introduced until the pressure in the chiller exceeds __ in order to make sure that water doesn’t freeze in the evaporator tubes
17” hg
