1.Why do some condensers have to be cleaned with brushes and others with chemicals?
Straight condensers can be cleaned with brushes and coiled condensers have to be cleaned with chemicals.
2.Three metals that condensers are made of are
copper, aluminum, and steel.
3.Who should be consulted when condenser cleaning is needed?
Someone who is experienced in cleaning and handling chemicals.
4.When is most heat removed from the refrigerant in the condensing process?
From change of state from vapor to liquid.
5.After heat is absorbed into a condenser medium in water cooled condenser the heat is deposited in one of two places. What are they?
Cooling towers or water that is wasted down the drains.
6.Water cooling tower capacity is governed by what aspect of ambient air?
(B) Wet-bulb temperature
7.When a standard efficiency air cooled condenser is used, the condensing refrigerant will normally be
30 degree F.
8.Four methods for controlling head pressure in an air cooled condenser are
fan cycling, air shutters or dampers, condenser flooding, and variable speed condenser fan motors.
9.The prevailing winds can affect which of the air cooled condensers?
Vertical coil type condensers
10.T or F: Air cooled condensers are much more efficient than water cooled condensers?
False
11.The type of condenser that has lowest operating head pressure is the
water cooled condenser.
12.Compare standard conditions of high efficiency and standard air cooled condensers
. Standard temperature for high efficiency is 10-15 degree F above ambient temperature on a 95 degree F day. Condensing temperature for standard would be approximately 30 degree F above ambient.
13.Name two ways in which the heat from an air cooled condenser can be used for reclaiming heat.
Heat domestic water (water heater) or heat exchange in a duct to add heat into a building.
14.Briefly describe what is meant by floating head pressure, and tell why is used in refrigeration and air conditioning systems
. Floating head pressure let condensing pressure follow ambient temperature as seasons move from summer to winter. The lower condensing pressure will save energy from the compressor operating at a lower compressing ratio.
15.Explain how to flush impurities from a water regulating valve that is on a water cooled condenser.
Prying the spring in the valve with tow standard slot screwdrivers will rid body of scale, dirt or sand.
16.Explain the basic operation of a combination ORI and ORD low ambient head pressure control valve.
ORI valve sensed drop in condensing pressure and will throttle shut creating pressure difference across the ORD valve. ORD valve senses factory preset pressure difference of 20 psi between receiver and compressor discharge, it will open and bypass hot com
17.Name two problems a refrigeration system may have if the condensing unit is exposed to a low ambient condition when not equipped with a low ambient head pressure control valve.
Low temperatures can cause condensers to have insufficient refrigerant flow rates through metering devices and starved evaporator coils.
18.Briefly explain what is meant by condenser splitting, and list its main advantage.
Way to reduce amount of extra refrigerant charge needed for condenser flooding is to split condenser into two identical condenser circuits, the advantage is keeping reasonable head pressure in colder temperatures while not having to hold excessive amounts