Type 2 Flashcards
Comfort Cooling
Air-conditioning appliances used to supply cooling in order to control heat and/or humidity in occupied facilities
Commercial Refrigeration
Appliances (equipment) used to preserve products, as in the retail food and cold storage warehouse sectors
How do you determine system charge?
Use the charge stated on the equipment nameplate to determine normal charge for leak rate calculations when the system is a packaged system at the factory
Maximum leak rate for comfort cooling systems
10%
Maximum leak rate for commercial refrigeration
20%
Maximum leak rate for industrial process refrigeration
30%
How many days does the owner operator have to repair an appliance containing 50 or more pounds of regulated refrigerant that has exceeded the threshold leak rate?
30 days to repair so that it leaks below the limit and conduct initial verification test
If an appliance with at charge of 200 pounds or more of a regulated refrigerant passes the initial verification leak test, a follow-up test mused be conducted in how many days?
10 days
How long can a leaking appliance with regulated refrigerant run without repair before it must be retrofitted or retired?
12 months
If that system leak rate exceeds ______ % of its full charge in a calendar year, then a report must be submitted to EPA describing the efforts to identify and repair system leaks.
125%
Frequency of Leak Inspection for Comfort Cooling systems 50 pounds or more
Once per calendar year until owner/operator can demonstrate leak has not exceeded 10% for one year
Frequency of Leak Inspection for Commercial and Industrial Process 50 to 500 pounds
Once per calendar year until owner/operator can demonstrate leak has not exceeded 20% for commercial or 30% (IPR) for one year
Frequency of Leak Inspection for Commercial and Industrial Process more than 500 pounds
Once every three months until owner/operator demonstrates leak has not exceeded 20% commercial or 30% (IPR) for four quarters in a row
How long must records remain on file by owner/operator?
3 years. Leak inspections, initial leak verifcation and follow-up verification tests
Can system-dependent recovery methods be used on systems greater than 15 pounds?
NO
Gauge hoses used in recovery are required to have what?
self-sealing connectors or hand valves to minimize refrigerant release when hoses are connected or disconnected
To reduce recovery time, where should the service hoses be connected?
Liquid line and recover refrigerant in the liquid phase
All HVAC companies must keep records of disposed appliances for how long if the charge is between 5 and 50 pounds?
3 years
What can you do to the recovery cylinder to speed up recovery process?
Cool the cylinder to reduce pressure. You can also heat the refrigeration system
Recovery level for Medium-pressure appliances with full charge of less than 200 lb of refrigerant
10 hg
Recovery level for Medium-pressure appliances with full charge of 200 lb or more of refrigerant
15 hg
Recovery level for High-pressure appliances with full charge of 200 lb or more of refrigerant
10 hg
Recovery level for High-pressure appliances with full charge of less than 200 lb of refrigerant
0 hg
Recovery level for Very-High pressure appliances
0 hg
Where is the refrigerant receiver typically found?
In the liquid line, at the outlet of the condenser when a system uses a TXV.
What should be used to remove ice from the sight or viewing glass?
Isopropyl alcohol
Anytime a system is opened for service, what should be replaced?
Liquid-line filter drier
What is an accumulator’s function?
Prevent any liquid refrigerant that may flow from the evaporator from flowing into the compressor
Can the compressor operate with the discharge service valve closed?
NO, this will cause damage
Nitrogen tanks require what?
Pressure regulators. Never install pressure relief valves in series.
In an R410A chilled-water system, vapor is charged from a vacuum level to a pressure of approximately ______ psig corresponding to 36 degrees F to prevent freezing
110 psig; understand PT chart relationships
