Accessories Ppt notes page 1+2 Flashcards
What is the purpose of a filter drier?
To filter refrigerant from particles such as dirt, metal, or chips
A ______-line drier is permanent and must be replaced every time the system _____
liquid line drier
opens
Suction line drier - used on service calls when putting in a new ___________ you add it to the suction line to ________ the compressor. It is for ___________ use.
compressor
protect
temporary
_______ is the process in which substance accumulated on the surface of a solid forming a thin film one molecule thick.
Example: activated charcoal can adsorb certain gases
Adsorb
_______ is the process in which a substance is dissolved into another substance
Example: water absorbs ammonia in a natural chemical process
absorb
Filter Drier Components;
_______ collect foreign matter
_______ Is a material that removes and traps moistures and acids in the refrigerant liquid
Strainers
Desiccant
Filter Driers; Types of Desiccants used:
- _____ gel: molecular sieve (adsorbent substances)
- _______ charcoal: Acid/Wax removal
- Activated ________ : Acid removal
- Newest type: _________
- silica gel
- Activated charcoal
- Activated Alumina
- Zeolite
Refrigerant drying capacity:
- Normally rated at approx ___F to _____F
- will maintain a systems water content below ___PPM for most refrigerant
- Drier size is based on a systems ________
- If filter drier is different temp then there is ____ gas and it is not operating correctly
- 75F to 125F
- 15PPM
- capacity
- flash gas
Filter Driers and Refrigerants:
- Most CFC and HCFC refrigerants should be dried to a maximum allowable moisture content of ____PPM
- Most HFC refrigerants should be drier to a max allowable moisture content of ___PPM
- Moisture content exceeding these levels causes system _________ which results in oil breakdown, sludge, motor burnouts, copper plating
- 15PPM
- 25PPM
- System contamination
Liquid line drier: Location;
- *Installed as close to _____ inlet as possible. Should be ___________ to any system
- Driers are ________ as indicated by arrow
- Normal operation no ____ across the drier
- evap inlet, permanent to any system
- directional
- TD
Suction Line Drier: Construction;
- Similar to ______ ____ drier
- Normally _______ size than liquid line drier
- has ______ valves for P/D testing
- liquid line drier
- larger
- access valves
Desiccants use a combination of;
2.
3.
- molecular sieve
- charcoal
- activated alumina
Suction Line driers: Textbook answers;
- _________ use only
- To protect new __________ only
- Must go back to check if there is too much ______ drop or go back to ______ it if is no longer required
- temporary
- compressor
- pressure drop, remove it
Suction Line Drier: Application;
- Used after a _____ ________or severe system contamination for removal of acids, wax, sludge, and moisture
- Installed as close to comp _____ as possible
- Removal or replacement is determined by ______ ____ across the assembly or after ____hrs of operation
- motor burnout
- compressor inlet
- pressure drop, 72hours
Moisture Indicating sight glass: Purpose;
- Indication of ref ______
- Moisture content of __________
- Indication of _____ gas
- Reading of _______ indication
- Ideal liquid temp approx ___F to ___F
- Installed upstream of downstream of ____
- _______ indicators are suitable for CFC, HCFC, and HFC refrigerants
- charge
- refrigerant
- flash gas
- moisture indication
- 75F to 90F
- upstream or downstream of drier
- moisture indicators
Sight glass installation: Location;
- Installed as close to _______ device as possible to indicate ____ gas
- Installed at the _________ unit to assist in refrigerant charging
- metering device, indicate flash gas
2. Condensing unit
Suction Line Accumulator;
- Also known as suction ____ or _____ tank
- also a storage tank for heat pump systems without _______
- Purpose: To prevent liquid refrigerant from entering the _________ during running or off cycles
- Protects compressor from too much _____
- Suction trap or Surge tank
- receivers
- compressor
- liquid
Suction Line Accumulators: Use;
When minimum superheat cannot be obtained thus guarding against;
- Liquid _______
- Liquid _______
- Liquid _______
- flooding
- dilution
- slugging
Suction Line Accumulator use:
- Must use an _______ on a hot gas defrost system
- Used when an ____ is used
- Used on some heat pumps and also acts as a temporary _______
- accumulator
- AXV
- receiver
Suction Line Accumulator: Installation;
- located as close to the compressor as possible downstream from all other accessories of sized at ___% of system charge
- Located upstream from CPR if sized at ___% of system charge
- Normally installed on low temp ____-hermetic compressors
- sometimes not required on low temp ______ systems
- under normal conditions they should not be _______. Some units have built in heaters, and some have coiled hot gas discharge or liquid lines inside shell
- 50%
- 100%
- low temp semi hermetic
- hermetic
- insulated
Crankcase pressure regulator (CPR) closes on a ____ of _____
closes on a rise of outlet (CRO)
Crankcase Pressure Regulator: Purpose;
- To limit pressure to a low temp _____ during hot pull down and defrost thus preventing compressor _________
- protects compressor from overloading due to high _____ pressure
- CRO depends on ______ pressure
- compressor, overloading
- outlet pressure
- outlet pressure
Crankcase Pressure Regulator is located in the ____ line close to the compressor, _____stream from any other accessory
suction line
downstream
