EPA 608 Type 3 questions with correct answers On low pressure chillers, moisture typically enters the refrigerant system through ans ✓✓ air leaks from areas with gaskets or fittings The maximum test pressure for leak testing a low pressure centrifugal is: ans ✓✓ 10 psig Leak test and repair the chiller to reduce refrigerant loss from a pruge unit on CFC- 11 chiller ans ✓✓ ...A hydrostatic tube test kit is used to: ans ✓✓ determine if a tube leaks Commercial and industrial process refrigeration systems must be repaired when the leak rate exceeds ____ of the charge per year. ans ✓✓ 35% Refrigerant recovery typically start with liquid recovery it is faster. ans ✓✓ ...A rupture disc on a recovery vessel for a low pressure refrigerants relieves at: ans ✓✓ 15 psig According to ASHRAE Guideline 3-1996, if the pressure in a system rises from 1 mm Hg to a level above ____ during a standing vacuum test, the system should be checked for leaks. ans ✓✓ 2.5 mm Hg The primary water source for a recovery unit condensing coil is _____. ans ✓✓ local municipal water supply 1 / 3
When recharging a refrigeration system with R-11, what vaporpressure is necessary in the shells before changing with liquid? ans ✓✓ 16.9" Hg vacuum After recovering the liquid refrigerant you must: ans ✓✓ recover the vapor refrigerant According to the EPA there is approximately _____ refrigerant vapor left in an average 350 ton R-11 chiller at 0 psig pressure once all the R-11 liquid has been removed. ans ✓✓ 100 pounds Charging refrigerant liquid into a refrigeration system when it is under a 29 inch
Hg vacuum can cause the: ans ✓✓ system water to freeze
A system does not have to be evacuated all the way to the required level when:
ans ✓✓ leaks in the appliance make evacuation to the prescribed level unattainable Which of the foloowing repairs would ALWAYS be considered "major" under EPA's ans ✓✓ replacement of evaporator coil Under EPA's regulation's _______ is used to pressurize a low pressure chiller for the purpose of opening the system for a non major repair? ans ✓✓ warming the refrigerant If you are using a recovery machine manufactored AFTER 11-15-93 you must evacuate an low pressure appliance to _______ before making a major repair. ans ✓✓ 25 mm of Hg absolute 2 / 3
After reaching the required recovery vacuum on a chiller, you should ans ✓✓ Wait for at least a few minutes to see if the system pressure rises, indicating that there is till refrigerant in a liquid form or in the oil The pressure corresponding to 32 F for R-123 ans ✓✓ 20 inches of HG vacuum When evacuating a system the use of too large a vacuum pump can cause? ans ✓✓ trapped water to freeze Refrigerant-11 at a pressure of 17 inches HG vacuum has a saturation temperature
of: ans ✓✓ 35F
During the evacuation of a system containing large amounts of moisture you can prevent freezing of this moisture by increasing the pressure with______gas ans ✓✓ nitrogen ASHRAE standard 15-1994 requires that each machinery room must activate an alarm and mechanical ventilation beofre refrigerant concentrations exceed: ans ✓✓ the threshold limit valve and time weighted average The typical design burst pressure for a rupture disk on a low pressure centrifugal air-conditioning system is set at_______ ans ✓✓ 15 psi Heat pumps that have been retrofitted from R22 to R407C should be leak checked
with: ans ✓✓ pressurized nitrogen
When a new system has been assembled, the first thing to do is: ans ✓✓
pressurize the system with inert gas and leak check
- / 3