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EPA 608 starting with 3rid part
HVAC
144
Other
Not Applicable
10/01/2011
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Term
tank color of R 12
 Definition
R 12 White
Term
tank color of R 11
 Definition
orange
Term
tank color of R 22
 Definition
green
Term
tank color of R 134
 Definition
blue
Term
tank color of R 500
 Definition
yellow
Term
tank color of R 502
 Definition
orchid
Term
What type equipment does type test level 3 deal with
 Definition
low pressure
Term
What is the date that only certified techs could buy refrigerant and what is the minimum allowed to buy
 Definition
November 14, 1994 20 pounds
Term
Where are leaks likely in low pressure equipment? and what happens?
 Definition
gaskets and fittings air and moisure is pulled into the system.
Term
What is the best leak check for low pressure equipment?
 Definition
pressurize with hot water or hot blankets
Term
To leak check with no way of heating what can you use? and what is the limit to pressurize? And why?
 Definition
you can use nitrogen to increase pressure. Not to exceed 10 PSIG. or rupture disk fails.
Term
Leak testing a water box how?
 Definition
remove the water then place a leak detector probe throuh the drain valve.
Term
To leak test a tube what do you use?
 Definition
a hydrostatic tube test kit.
Term
Systems with an open drive compressor is likely to leak where?
 Definition
at the shaft seal
Term
What can you use to open the system for a non-major repair?
 Definition
Controlled hot water to pressurize.
Term
Repair  leaks in comfort cooling systems having more that 50 lbs must be made when what rate of refrigerant loss?
 Definition
when annual leak is over 15%
Term
system with more than 50 lbs repair wen leak rate is what?
 Definition
over 35% annual rate.
Term
A recovery unit's high pressure cut-out is set for what?
The ruputre disc on a low presure chiller recovery vessel relieves at what?
 Definition
10 psig when evacuating the R from a low-presure chiller.
relieves at 15 psig.
Term
Recovery of R 11 and $ 123 starts with what?
 Definition
liquid then vapor. a lot of vapor can be left after the liquid.
Term
How do you preven freezing the water when evavuating R?
 Definition
circulate the water.
Term
When recovering R what do you leave on?
 Definition
the water pumps, recovery compressor, recovery condenser stay on.
Term
What is connected to the water cooled condenser
 Definition
the municipal water supply
Term
What should you do if you think a chiller has a tube leak?
 Definition
the water sides of the evaporator and condenser should be drained prior to recovery of the refrigerant.
Term
ASHRAE guide 3-1996 says if the pressure in a system rises during vacuum testing the system should be leak checked. how much rise?
 Definition
pressure rises from 1 mm HG to above 2.5mm Hg during vacuum.
Term
To what and where is the refrigerant added
 Definition
The lowest access point. The evaporator charging valve.
Term
In what form is the R in the initial charging and why.
 Definition
Initial chargin is in the vapor phase. Introducing liquid R into a deep vacuum with cause refrigerant to boil and freeze water in the tubes.
Term
Before chargin with liquid an R 11 refrigeration system requires what?
 Definition
a vapor presure of 16.9 hg vacuum or a saturation temperature of 36 degrees F.
Term
R recovery and R recycling equipment made after November 15, 1993 must what?
 Definition
certified and labeled by EPA testng and must have low loss fittings for when hoses are disconnected.
Term
What is the date that all recovery and recycling equipment must be certified and labeled and have low loss fittings?
 Definition
November 15, 1993
Term
equipment made before Nov 15, 1993 must reach what level
 Definition
25 inches Hg
Term
equipment made AFTER Nov 15, 1993 must reach what level
 Definition
25 mm Hg absolute
Term
Once the required vacuum level has been achieved and held what do you do if the presure rises and what does that indicate?
 Definition
there is refrigerant remaining in the system and you have to repeat the recovery. If it is from a leak just evacuate to the lowest possible level before making a major repair.
Term
Because chillers that use R such as CFC 11 and CFC 123 opeerate below atmospheric pressure what do they require? And Why?
 Definition
A purge unit. To remove non-condensables from the system..
Term
Where does a centrifugal chiller's purge condensing unit take its suction from? and where does it return the refrigerant?
 Definition
From the top of the CONDENSER.
Returns to the EVAPORATOR
Term
What does frequent purging indicate?
and what can accompany it?
 Definition
Leak
refrigerant loss
Term
What does high discharge presure indicate?
 Definition
Air in the system and thus maybe a leak
Term
What does excess moisture collection in the purge unit mean?
 Definition
tube leakage
Term
Where is the rupture disk mounted and what is it's function? what's it set for?
 Definition
On the evaporator housing. protection from over-pressurizing and its burst pressure is 15 psig.
Term
?What does TLV-TWA mean and what happens
 Definition
threshold limit value -time weighted average. It is an ASHRAE standar 15. refrigerant monitor alarm to start ventilation before R concentration in a room reaches TLV-TWA
Term
What are grouped at A-1 refrigerants?
 Definition
CFC 12 CFC 11 CFC 134 a
Term
What is a group B 1
 Definition
R - 123
Term
all refrigeration systems must have what protection?
 Definition
a pressure relief valve not installed in series.
Term
What do metering devices do regarding temperature and pressure?
 Definition
reduce pressure. reduce saturation temperature.
Term
Where does refrigerant boil?
 Definition
Evaporator caused by heat being absorbed and it boils into a vapor by the time it gets to the compressor and is superheated.
Term
The thermostatic expansion valve has what and where is it located?
 Definition
a reciever in the liquid line directly following the condenser.
Term
a capillary tube or bore meter device has what and where is it located?
 Definition
accumulator in the suction line directly follow the evaporator.
Term
what is the gage manifold to measure?
and what terms and numbers?
 Definition
pressures.
compound, low in psig and vacuum in inches of Hg
and high side or diacharge in psig I guess.
Term
what is the center port and what color is it.
 Definition
Yellow; it connects to a recovery device, or evacuation vacuum pump, or a harging device. it can charge, recover, or evacuate.
Term
What are you studying?
 Definition
section 608 of the Federal Clean act that is regulated by the EPA.
Term
as of what date must you be certified
 Definition
Nov 14, 1994
Term
When was it declared unlawful to vent CFC or HCFC?
 Definition
July 1, 1991
Term
When was it declared unlawful to vent HFC?
 Definition
November 15, 1995.
Term
when were CFC's phased out of production?
 Definition
DEC 31, 1995.
Term
what are the 3 R's?
 Definition
recover recycle reclaim
Term
recover
 Definition
remove + store
Term
recycle
 Definition
cean by separating oil from R and removing H2O by passing it through filter driers
Term
Reclaim
 Definition
To resell it. make it like new
ARI 700 standards.
Term
Equipment must be certified as of
 Definition
Nov 15, 1993
Term
which recovery uses the compresssor as a pump?
 Definition
system dependent
Term
which recovery equipment work on it's own?
 Definition
self-contained.
Term
As of what date can only certified techs buy CFC or HCFC R? and the limit
 Definition
Nov 14, 1994
Have to buy 20 lbs or more
Term
What kind of oil does the Ozone friendly R 134 a use?
 Definition
ESTERS.
Term
after a retrofit what can R 134 be used in?
 Definition
R 12 systems after a lot of retrofiting.
Term
What kind of oil do Ternary blends use?
and what's funny about that oil?
what should you do if a major component failure?
 Definition
synthetic alkylbenzene lubricant.
It is hygroscopic (hydrophylic).
Take an oil sample for analysis.
Term
What's funny about blends?
 Definition
they will leak at uneven rates due to different vapor pressures.
Term
How do you charge blended refrigerants?
 Definition
Weight into the high side of the system as a liquid. LIQUID CHARGE BLENDS
Term
Temperature glide
 Definition
refers to R blend tht has a range of boiling points or condensing points throughout the evaporator and condenser.
Term
Azeotropic
 Definition
doesn't act like a mix...Has no temperature glide even though it is a mix it acts like one refrigerant.
Term
service aperture or process stub
 Definition
EPA require on all appliances with class 1 and class 2 R to recover refrigerant.
Term
What do you do if you find 2 or more R have been mixed in a system?
 Definition
Do not mix the refrigerants in the same recovery tank or you won't be able to reclaim it. Recover the mix into seperate tanks. recover only one type refrigerant into a recovery cylinder.
Term
What effects the efficiency and speed of recoverty?
 Definition
lenth of hoses, outside temp. Winter takes a long time. moisture in system.
size of vacuum pump and suction line. pump should be short and fat and gauge far from vaccum pump.
Term
After your done transfering liquid R between a recoveryu unit and a refrigeration syst what do you guard against?
 Definition
trapping liquid refrigerant between the servvice valves.
Term
what happens when moisture is allowed to remain in an operating refrigeration system? and how do you get it out?
 Definition
hydrochloric and hydroflluoric acid form.
Evacuate the system to the mandated vacuum level.
Term
measuring a systems vacuum is done when what?
 Definition
system isolated and vacuum pump off.
Term
What's another thing you can do to save time when dehydrating? when do you know the dehydration is complete?
 Definition
Heat the refrigeration system. You're done when it holds the required vacuum.
Term
How many ports does a recovery cylinder have. How do you check how full it is?
 Definition
2 ports, one liquid and one vapro. 80% max to fill. controlled by mechanical float device, electronic shout off device (thermistors), or weight.
Term
Before discarding a RUSTY cylinder what do you do.
 Definition
reduced to 0 psid and diacarded.
Term
What is important about safety and nitrogen pressurizing?
 Definition
You must alway charge through a pressure regulatyor and insert a relief valve in the down stream line from the pressure regulator. relief valve NOT installed in series. Watch for corrosion buildup and replace when found.
Term
What else should you inspect?
 Definition
Schrader valves for leaks, bends and breakage. Have to cap the schrader valve.
Term
In the event of a big release of R in a confined area what must you have?
 Definition
SCBA. other wise run.
Term
What do R 12 and R 22 decompose to if exposed to open flames or glowing how metal?
 Definition
hydrochloric acid, hydrofluoric acid and phosgene gas.
Term
What do you put on cylinders to ship.
 Definition
DOT paper. numbefr of cylinders of each R. label the cylinders with type and aount. DOT clasification tag ...it is a 2.2 non-flammable gas.
Term
Type 1 techs work on sealed systems,I think. Type 1 techs work on small appliances. What is a small appliance?
 Definition
It is made, charged, hermetically sealed in a factory with 5 lbs or less of refrigerant.
Term
Recovery equipment made when must be capable of reoving how much refrigerant whether or nhot the compressor is operating..or achieve how many inches of vaccum under conditions of what?
 Definition
BEFORE Nov 15 1993 80% 4" HG ARI 740
AFTER Nov 15 1993 90% with compressor
80% no compressor
or 4" vacuum
+ AFTER Nov 15, 1993 recovery equipment must be certified by EPA test lab
Term
First of all before beginning recovery
 Definition
Know what kind of refrigerant
Term
What kind of cylinders do self contained active recfovery equipment use?
 Definition
a pressurized recovery tnk.
Term
Before operating a self contained recovery machine make sure of what?
 Definition
The tank inlet valve is open
and the tank does not have excessive non-condensables.
Term
How do you know a tank doesn't have excessive non-condensibles?
 Definition
An accurate pressure reading of R inside a recovery cylinder. you have to know the temperature and the temperature must be stable to read pressure.
Term
What will cause higher discharge pressure in a refrigeration system?
 Definition
Air
Term
how do you find out how to purge the recovery equipment of non-condensibles?
 Definition
follow the instructions suppled by the recovery equipment manufacturer.
Term
Every day what do you have to check?
 Definition
All refrigerant recovery equipment for oil level and refrigerant leaks.
Term
What kind of container do system dependent passive recovery process use to capture refrigerant for a small appliance?
 Definition
non-pressurized container...maybe charcoal activated plastic bags.
Term
How does system dependent equipment get the refrigerant?
 Definition
with the appliance compressor, an external heat source, or a vacuum pump.
Term
What kind of container can a standard vacuum pump be used with as a recovery device?
 Definition
a non-pressurized container.
Term
When using a system dependent on an appliance with an operating compressor what do you do and where do you recover?
 Definition
run the compressor and recover from the high side of the system. Only the high side is needed if the compressor runs.
Term
What if the compressor doesn't run and your using a system dependent passive recovery machine?
 Definition
Use both the high and low side. Plus you have to heat and tap the compressor and or use a vacuum pump to get the rest.
Term
What if you can't get the required vacuum using a system dependent recovery machine and an appliance with a non working compressor?
 Definition
You are required by the EPA to have a self contained recovery device at the shop to use. The exception is tech working on small appliances only.
Term
What kind of appliances are system dependent devices used on?
 Definition
Appliances containing 15 lbs of refrigerant or less.
Term
What do you use on a small appliance with a straight piece of tubing ?
 Definition
Install a piercing type access fitting.
and you have to leak test it and cannot leave it in place afterwards.
Term
When would you not start recovery ?
 Definition
If the system pressure is 0 psig.
Term
After recovering refrigerant what do you do to the system?
 Definition
Flush with nitrogen to flus debris out of the system.
Term
What year did systems use refrigerant you should not recover with current devices.
 Definition
refrigerators built before 1950.
Term
What do type 2 techs work on
 Definition
high or very high pressure appliances.
Term
After installation of any system what must you do?
 Definition
pressurize with nitrogen and leak check it.
Term
How do you find a leak?
 Definition
an electronic or ultrasonic leak detector..to find genera area and then soap bubbles to pin point.
Term
a unit with an open compresson not used in several months will often leak where?
 Definition
from the rotating shaft seal.
Term
What is an indication of a leak?
 Definition
traces of oil
Term
What is another indication of a leak in a high pressure system?
 Definition
excessive superheat from low charge in a high pressure system
Term
How much can a comfort appliance leak if it has more than 50 lbs of R before you have to fix it?
 Definition
when the annual leak rate is more than 15%.
Term
You better know how to figure leak rates.
 Definition
so if 15% of 50 is 7.5 then if you find a leak that would add up to more than that in a year you have to fix it I think.
Term
how much can a commercial system with more than 50 pounds leak in a year before you have to fix it?
 Definition
More than 35% in a year. so it it has 50 lbs 35% is 17.5 so it monthly it would add up to more than that you fix it. I guess.
Term
What about your recovery equipment?
 Definition
It must be apropriate and be certified by and EPA approved labe (UL or ETL) to meet or exceed ARI standards.
Term
Talk about care of the recycling machine.
 Definition
Refrigerants might have acides, moisture, and oil so you must check and change the oil and filter on a recycling machine. Recycling and recovery equipment have hermetic compressors and can overheat when drawing a deep vacuum because the unit uses the flow of refrigerant through the compressor for cooling.
Term
Before using a recovery unit you always check what?
 Definition
the service vaalve position , the oil level of of the recovery unit, ande evacuate and recover any remaining refrigerant from the units reveiver.
Term
If you work with multiple refrigerant, before recovering or recycling a different refrigerant what do you have to do?
 Definition
Purge the recover/recycle equipment by recovering as much of the first refrigerant as possible, change the filter and evacuate.
Term
What do you have to do if you work with R 134 A?
 Definition
Provide a special set of hoses, guages, vacuum pump, recovery or recovery/recycle machine, and oil containers to be used with R 134 a ONLY.
Term
What will reduce time but talk about oil too.
 Definition
recovering in vapor will minimize the loss of oil. But recoverina as much as possible in liuid can save time.
Term
What else can you do to save time?
 Definition
Ice the the recovery cylinder and apply heat to the appliance. AFter recovering liquid any remaining vapor is condensed by the recovery system.
Term
What if the unit being serviced has a receiver/storage tank?
 Definition
refrigerant should be placed in the receiver. So refrigerant should be remjoved from the condenser outlet if the condenser is below the receiver.
Term
If there is an air cooled condenser on the roof and an evaporator on the first floor where do you begin recovery?
 Definition
recovery should begin from the liquid line entering the evaporator.
Term
Recovery and/or equipment made after when must be certifed and labeled by EPA?
 Definition
Nov 15 1993
Term
Type 2 appliances with R 22 with less than 200 lbs of R require vacuum of wht levels in inches.
 Definition
0 zero both before and after Nov 15, 1993
Term
type 2 appliances with R 22 with MORE than 200 lbs of R require what vacuum
 Definition
4 before Nov 15 1993
10 after Nov 15 1993
if > 200 lbs
Term
Other high pressure appliances with less than 200 lbs require how much?
 Definition
4 before Nov 15, 1993
10 after Nov 15, 1993
Term
Other high pressure appliances with MORE than 200 lbs
 Definition
4 before November 15, 1993
15 after November 15, 1993.
Term
Very high pressure appliances
 Definition
are 0 zero before and after Nov 15, 1993.
Term
After you reach the desire vacuum and wait. What if the pressure rises?
 Definition
It indicates there is still refrigerant in liquid form or in the oil.
Term
What do you do if there are leaks making evacuation impossible.
 Definition
evacuate to atmospheric pressure 0- psig.
Term
What must you do with parallel comprssor systems to recover refrigerant. and what will happen if you don't do this?
 Definition
You must isolate a parallel compressor system in orer to recover refrigerant. If no a parallel compressor system will cause an open equalization connection that will preen refrigerant recovery.
Term
What is the limit of system recovery equipment.
 Definition
It cannot be used on appliances with more than 15 pounds of refrigerant.
Term
what was the most common refrigerant used in residential split air conditioning systems.
 Definition
R - 22 but look at the name plate to determine the type of refrigerant used.
Term
Some system have moisture indicating sight glass. How do they work?
 Definition
The sight glass changes color if the system has excessive moisture and need to be eacuated.
Term
When should the filter drier be replaced?
 Definition
anytime a system is opened for servicing.
Term
What is used to prevent refrigerant from migrating to the oil during cold weather? What is an indication refrigerant is in the oil?
 Definition
A crankcase heater prevent refrigerant from migrating into the oil refrigerant in the oil will cause oil to foam in the compressor at start up.
Term
When evacuating a vapor compression system, the vacuum pump should be capable of what?
 Definition
Pulling 500 microns (29.9 " hg) of vacuum. Microns is the more accurate measurement.
Term
What should you never do in a deep vacuum.
 Definition
energize a hermetic compressor's motor...the motor winding could be damaged by starting in a deep vacuum.
Term
What if you use a large vacuum pump?
what can happen and what do you do?
 Definition
a large vacuum pump could cause trapped water to freeze. you may have to increase presure by introducing nitrogen to counteract freezing.
Term
What is the source of most non-condensables?
 Definition
air.
Term
Non-condensables cause what
 Definition
a higher discharge pressure
Term
Where there is a risk of freezing in charging liquid R - 12 system what should you do?
 Definition
Begin with vapor from a vacuum level to a pressure af about 33 psig. Followed by a liquid charge through the liquid-line service valve.
Term
What is the proper method to charge a system that contain a large quantity of refrigerant.
 Definition
Begin with vapor from a vacuum level to a pressure af about 33 psig. Followed by a liquid charge through the liquid-line service valve
Term
What are category A 1 refrigerants
 Definition
CFC-12 CFC-11 HFC - 134 a
Term
ALL refrigeration system must be protected by
 Definition
a pressure relief valve not installed in series
Term
NEVER do what
 Definition
energize a recriprocating compressor is the discharge service valve is closed
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