Skills and Trades

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The amount of outside air introduced can be controlled using A) an N2 sensor B) a CO2 sensor C) a ... Started by ENagel	1 Replies 14 Views	Jul 27, 2018 by abctaiwan
In a single zone constant air volume system, the amount of air moving through the air handler A) ... Started by j.rubin	1 Replies 28 Views	Jul 27, 2018 by atrochim
In multi-zone systems with one trunk duct to each zone, what is used to adjust the temperature of ... Started by dejastew	3 Replies 32 Views	Jul 27, 2018 by LVPMS
A unique feature of multi-zone and double duct systems is that they A) can heat and cool at the ... Started by bobbie	1 Replies 57 Views	Jul 27, 2018 by soda0602
How does an energy recovery wheel transfer latent heat between the ventilation and exhaust air? ... Started by maegan_martin	1 Replies 20 Views	Jul 27, 2018 by Pariscourtney
What do air quality sensors measure? A) temperature, velocity, and pressure B) O2 and NOx levels ... Started by luvbio	1 Replies 52 Views	Jul 27, 2018 by Jadwiga9
Constant air volume systems can deliver different levels of heating or cooling A) by blocking ... Started by misspop	3 Replies 34 Views	Jul 27, 2018 by abctaiwan
When a two way control valve reduces the flow through the coil by A) opening and closing in ... Started by joe	1 Replies 56 Views	Jul 27, 2018 by vickybb89
Pneumatic control systems A) are the most recent type of commercial control B) Use air pressure ... Started by Sufayan.ah	1 Replies 36 Views	Jul 27, 2018 by AISCAMPING
The general types of commercial control systems include A) Electro-mechanical, electronic, ... Started by corkyiscool3328	1 Replies 356 Views	Jul 27, 2018 by abro1885
In a direct expansion chiller, the chilled water is circulated A) over the outside of the chiller ... Started by mcmcdaniel	3 Replies 52 Views	Jul 27, 2018 by FergA
Purged air is released from the A) bottom of the condenser. B) bottom of the chiller. C) top of ... Started by olgavictoria	1 Replies 51 Views	Jul 27, 2018 by trog
Smaller chillers typically use A) centrifugal or screw compressors B) centrifugal or rotary ... Started by B	1 Replies 32 Views	Jul 27, 2018 by kbennett34
The refrigerant in an absorption chiller is A) lithium bromide B) HCFC 123 C) water D) HFC ... Started by cabate	1 Replies 21 Views	Jul 27, 2018 by leahchrapun
What is an open piping system? A) An open piping system has components that can be disassembled ... Started by nautica902	3 Replies 55 Views	Jul 27, 2018 by pratush dev
What does a mixing valve do in a hydronic heating system? A) it mixes hot water from the boiler ... Started by LCritchfi	1 Replies 55 Views	Jul 27, 2018 by ntsoane kedibone
What is the purpose of bypass piping on a hot water gas fired boiler? A) ensure that the return ... Started by Jramos095	1 Replies 34 Views	Jul 27, 2018 by Ddddd
What is the maximum working pressure for a low pressure steam boiler? A) 10 psi B) 100 psi C) 15 ... Started by BrownTown3	1 Replies 59 Views	Jul 27, 2018 by ansleighelindsey
What is an advantage of a cross flow tower? A) Cross flow cooling towers have variable pitch air ... Started by deesands	3 Replies 52 Views	Jul 27, 2018 by diana chang
Mechanical draft towers are categorized as A) low pressure or high pressure B) packaged or split ... Started by saraeharris	1 Replies 50 Views	Jul 27, 2018 by jaykayy05
When antifreeze is added to water, its specific heat A) Increases, decreasing the cooling ability ... Started by MGLQZ	1 Replies 49 Views	Jul 27, 2018 by zoeyesther
Ice-harvesting systems A) use multiple banks of galvanized steel coils submerged underwater. B) ... Started by nenivikky	1 Replies 29 Views	Jul 27, 2018 by miss.ashley
Heat absorbed by the water during evaporation is called A) Specific heat B) Latent heat C) ... Started by Cooldude101	3 Replies 129 Views	Jul 27, 2018 by lkoler
A refrigerant that is a mixture of water and another chemical that has a lower freezing point than ... Started by ericka1	1 Replies 70 Views	Jul 27, 2018 by kishoreddi
What is meant by a PCM when referring to thermal storage systems? A) PCM stands for partially ... Started by sc00by25	1 Replies 28 Views	Jul 27, 2018 by sultana.d