Type III — Low-Pressure第 171 / 240 题
Which gas is safe to use, along with a trace of refrigerant, to raise pressure in a low-pressure appliance for leak detection?
a.Oxygen
b.Compressed shop air
c.Dry nitrogen
d.Acetylene
解析
Dry nitrogen is the correct pressurizing gas, sometimes with a small amount of refrigerant so an electronic detector can sense the leak. Oxygen or compressed air can combine with refrigerant oil and explode, and acetylene is a fuel gas. Even with nitrogen, never exceed 10 psig in a low-pressure appliance.
免费刷完整 240 道题库 — 无需注册。
同考点相关题目
- To speed up refrigerant recovery from a low-pressure chiller, a technician should:
- Frequent operation of the purge unit on a low-pressure chiller is usually a sign that:
- A low-pressure refrigerant is defined as one with a boiling point at atmospheric pressure that is:
- The 25 mm Hg absolute recovery requirement for low-pressure appliances applies to:
- Approximately what inches-of-mercury vacuum reading corresponds to the 25 mm Hg absolute recovery level for low-pressure appliances?
- Non-condensable gases such as air that collect in a low-pressure chiller will: