gw 50 spring 2025

To prevent noncondensables and contaminants from entering a refrigerant circuit, just before opening a system to atmosphere for service, a technician should _____.

• balance pressure with atmospheric pressure

• disconnect the gauge manifold

• increase pressure to at least 225 psi

• reduce pressure into a vacuum

A common method for reducing recovery time and preventing the development of high head pressure during recovery is to _____.

• immerse the recovery cylinder in an ice water bath

• run cold water over the condenser

• run cold water over the evaporator

• use a torch to gently warm the recovery cylinder

When pumping down a system, the best way to deal with safety controls that could cycle off the compressor is to _____.

• attempt to adjust their settings out of range

• completely disconnect them from the circuit

• connect a jumper wire across its terminals

• physically hold all the controls in the closed position

If an open-drive compressor is set down with its weight on its attached flywheel, a leak could develop at the _____.

• compressor head

• crankshaft seal

• inlet valve

• service valve packing

If a motor is part of a belt-driven unit, the motor can be lifted out after removing _____.

• the belt from the pulley

• contacts and wires

• fan hubs

• water pumps

A motor burnout in a hermetic compressor will result in the development of an _____ condition.

• acidic

• adiabatic

• alkaline

• azeotropic

When a motor burnout occurs, aside from the hermetic compressor, the rest of the refrigeration system can usually be reconditioned by flushing it with _____.

• ammonia

• butane

• muriatic solution

• nitrogen

Before adding refrigerant oil to a refrigeration system, ensure that the oil meets the following guidelines, except _____.

• able to work in the low-side temperature range

• compatible with the refrigerant

• has a high wax content

• proper viscosity for the compressor

Common methods of adding refrigerant oil to a refrigeration system include the following methods, except _____.

• drawing oil into the suction service valve through tubing immersed in an oil-filled container

• pouring oil into the liquid receiver service valve while the compressor is operating

• injecting oil manually using a hand pump

• pouring oil into the compressor crankcase after balancing pressure with atmosphere

Bent tubing fins on an air-cooled condenser can be straightened using a _____.

• pair of pliers

• torch and bare hands

• fin comb

• refrigeration service valve wrench