Steam & Hydronics Flashcards
Definition of steam
Gas form of water
Definition of saturated steam
Steam at 212°F
Definition of sensible heat
Heat that can be measured and felt
Definition of latent heat
Heat that changes the state but not the temperature
Definition of superheated steam
Steamy heated above the saturated state
Definition of pop safety relief
Relief that pops if unsafe pressures are present
Definition of water gauge
Sight glass
Definition of gauge cocks
Gate valve on a sight glass
Definition of compound gauge
Measures both temperature and pressure
Definition of additive differential pressuretrol
Controls operating pressure of boiler (additive= cutout+differential)
Definition of subtractive differential pressuretrol
Controls operating pressure of a boiler (subtractive= cutout-differential)
Definition of float low-water cut off
Low-water cut off operated by a float
Definition of electronic low-water cut off
Low-water cut off operated electronically
Definition of down feed system
System located below steam main
Definition of dry return
Any return above boiler water line
Definition of equalizing line
Equalizes the pressure between the main and the boiler
Definition of Hartford loop
Protects boiler against low water, 2”-4” below the water line
Definition of steam header
Horizontal piping connected to boiler outlet
Definition of wet return
Return lines below boiler waterline
What does CSD1 stand for
Control safety device 1
The function and purpose of a siphon tube
Keep steam from hitting gauges also known as pigtail
Definition of one pipe system
System with one type both supply and return are the same pipe
Definition of two pipe system
System with two pipes one supply and one return
What type of trap does a two pipe system use
Thermostatic trap
Name the major components of a steam system
Boiler, header, equalizer, Hartford loop, steam main, condensate main, traps, strainer, union, check, air vent, low-water cut off
How does a thermostatic trap operate
Operates on a difference in temperature
How does a mechanical trap operate
Operates on difference in density
How does a thermodynamic trap operate
Operates on difference in thermal energy
What is an equalizer and what does it do
Connects steam header to return, collects condensate from steam main and sends it to return
What type of trap is used on a low pressure system for end of main
A F&T trap beat because it will pass air and condensate
What does F&T trap stand for
Float and thermostatic
What controls the pressure in a low-pressure steam boiler
Pressuretrol
What PSIG does the safety relief valve on a low pressure boiler open at
15 PSIG
What is a drip pan ell used for
Drains condensate from a vent
What is used to view the water level in a boiler
Sight glass
Steam flow into a one a pipe radiator steam system is controlled by the what
Air vent
What is the normal pitch of steam piping
1 inch over 20 feet
In an F&T trap the float rises to discharge what
Air and steam
A failed trap will typically become what
Steam bound
Define high temperature high-pressure hot water
Hot water above 200°F and 60 PSIG
Why do you superheat steam
It does more work at lower pressures
List for common controls on a steam boiler
Manual reset, low-water cut off, aquastat, pressuretrol
Definition of reverse return
First in last out
Definition of parallel system
All piping is fed equally
Define primary, secondary
Lines set at 12 inch centers to avoid pressure drop
What is a closed hydronic system
A system of close to atmosphere
What is a open hydronic system
A system open the atmosphere
What is a zone system
A system with multiple zones that can be controlled independently of each other
What is a monoflow system
One pipe, use of monoflow tees, supply and return is the same pipe
What is a gravity system
System that flows by gravity alone by using the weight of water
What happens when water is heated
Molecules vibrate and move faster spreading apart
What are normal operating temperature for a hot water system
120 to 200°F
What is the maximum operating pressure of a boiler determined by
See level input
Why does the system stop circulating
Clogged pipe, air trapped, failed pump
Define set point
Temperature chosen that boiler is set to
Define domestic priority
Domestic water takes priority over hot water
Define circulator
Pump that circulates water in the system
Define indirect water heater
Water that is heated indirectly
Define bladder expansion tank
Unattached bladder that allows for expansion
Define diaphragm expansion tank
Attached diaphragm that allows for expansion
Define atmospheric compression expansion tank
Tank that is filled with a certain amount of air to allow for expansion
Define T&P relief
Relief controlled by temperature and pressure
Define pressure relief
Relief controlled by pressure
The steam piping on a steam boiler that reduces the likelihood of low-water condition in the boiler is called?
Hartford loop
Thermostatic traps open and close by means of
Flexible bellows
A failed trap will typically become
Steam bound
What is a vapor system
Vacuum system created by no mechanical means
What is a vacuum system
Vacuum system created by a pump
What is a vari vac system
Vacuum system created by a variable pump that creates a deep vacuum
True or false, radiant heat is not comfortable heat
False
True or false, radiant heat is found in the ceiling and the walls
True
True or false a hydronic heating system operating at 200° boiler water temperature can be used to heat domestic hot water to 120°
True
True or false a snowmelt system cannot be a part of a hydronic heating system
False
True or false, a typical temperature for snowmelt system is up to 114°
True
True or false a compression tank is not necessary in a system if a pressure reducing valve is used
False
True or false, plug a relief valve if it won’t stop dripping as a temporary fix
False
What are two factors which are used in establishing the pump size needed to circulate water through a piping system
Pressure drop\head, GPM\desired flow
What is the purpose of measuring the length of pipe in the longest circuit
To establish TEL, and account for pressure drop
How is the amount of added pressure drop determined for pipe fittings in a piping circuit
The longest circuit x 65 or each fitting accounted for on a short circuit runs with many fittings
What term is applied to the total measured length of the longest circuit and the length added for fitting allowance
TEL, total equivalent length
The available pump head per foot of pipe is usually expressed in what
Millinch/foot
Priming it happens because of
Incorrect piping
Foaming in a boiler happens when
Oily dirty pipes
To derate boiler you?
Multiply by the efficiency percentage in decimal form
True or false a three-way mixing valve enters on the AB port
False
What does a tridicator measure
Temperature, pressure, and vacuum
What is the maximum operating pressure of a boiler determined by
Maximum BTU input
Define outdoor reset
Provides less heating when outside temperature is higher than design the minimum
What does WWSD stand for
Warm weather shut down
Water flow into a hot water hydronic system is controlled by
Pressure reducing valve
Define refrigerant
Substance used for cooling that has a low boiling temperature
Define saturated air
Air that cannot hold any more water
True or false a room cooling unit removes heat and moisture from the air
True
True or false radiant heat is typically under 120° but used commercially up to 140°
True
True or false a closed hydronic heating system allows you to have higher water temperatures and better safeties
True
