Boiler Trim Flashcards
What is A?
Flow Control Valve
What is B?
Line scoop
What is C?
Automatic air vent
What is D?
Circulator
What is E?
Flow Switch
What is F?
Low water cut off.
What is G?
Temperature Gauge.
What is H?
Safety relief valve.
What is I ?
Diaphragm expansion tank.
What is J?
Pressure reducing valve.
What is K?
Backflow Device
What is L?
Drain Valve.
What is M?
Limit control and Operating control
What is N?
Combination Gauge.
What kind of boiler is this?
Natural draft boiler
What is this a diagram of?
Burner assembly
What is A?
Blocked inlet switch
What is B?
Air/Fuel valve
What is C?
Gas flex hose
What is D?
Staged Ignition Solenoid
What is E?
Igniter - Injector
What is F?
Blower proof switch
What is G?
Blower
What is H?
Burner plate
What is I?
Flame detector
What is J?
Oxygen sensor
What is K?
Burner
What is the maximum allowable temperature at the boiler outlet in a water boiler.
121 c or 250 f
On a water boiler when does a High limit control operate?
If the operating control fails.
What is a fluid temperature control used for on a water boiler?
As a control safety device to limit the fluid temperature in a boiler.
Where are limit controls wired to?
Wired to the gas valve, and close it when the high limit is reached.
What are the 3 most common water boilers?
Natural draft boiler
Forced draft modulating boiler
Forced draft modulating condensation boiler
What is the function of a Limit control?
Detect any dangerous high temperature condition that may occur in the heating system and prevent operation of the equipment until it is safe to do so.
What is the function of an Operating Control
A limit control that is used to maintain a variable condition within a set of desired range of values
What is the function of a Combination gauge?
Indicates pressure, feet of head, and temperature.
What is the function of the Safety relief valve?
Protects against excess pressure from thermal expansion.
What is the function of a thermometer on a water boiler?
Indicates temperature of water n the boiler, at or near the outlet or where the water returns .
What is the function of the pressure gauge?
Indicates pressure before and after the pump.
What is the function of the Flow control valve?
Prevents gravity circulation from occurring within the piping system.
What is the function of the air scoop?
Promotes the elimination of air and other gases from the hot water heating system.
What is the function of the automatic air vent?
Removes gases from the heating system
What is the function of the expansion tank?
Allows for continuous expansion and contraction of water within a closed water heating system.
What is the function of the Backflow device?
Stops reverse flow of boiler water back onto the domestic water system.
What is the function of the Pressure-reducing valve?
Reduces the city water pressure to a desirable working pressure for closed hydronic heating systems.
What is the function of the Circulator- inline circulation pump?
Circulates fluid within a how water heating system.
If an operating control has a mercury switch how must it be installed?
In a level position
What must a boiler be equipped with in addition to an operating temperature control ?
A safety limit
What are the 2 types of switches used in the basic operation of a temperature control?
Mercury switch or a micro switch
What are the 2 most common sensing elements found on aquastats?
Liquid bulb
Capillary tube
How is a sensing bulb inserted?
Inserted directly into the boiler and sealed with a packing gland and composition disk, or with an immersion well.
When can a surface-mounted aquastat be used?
If an opening is not provided.
What is the adjustable set point for an indoor-outdoor proportional control?
21c-60c
70f-140f
And indoor-outdoor proportional control has what reset ratio?
1:1
Boiler will increase by 1 degree for ever 1 degree outside drops.
What kind of sensing element is used in an indoor-outdoor proportional control?
2 capillary tubes
One outside and one inside
What 3 types of gauges are used in boiler trim?
Pressure Gauges
Thermometers
Tridicator/combination gauges
What are the 3 types of pressure gauges?
Bourdon
Bellow
Spiral
What is the most common pressure gauge with the widest range of applications?
Bourdon
Where must a thermometer be located on a boiler?
Must be located so that it will at all times indicate the temperature of the water in the boiler at or near the outlet.
Which 2 places must there be a thermometer on a boiler?
The supply and return mains
How do flow control valves differ from check valves
Flow controls use a weighted disc to prevent opening due to gravity of circulation.
What does a Boiler fitting do?
Separates gases from the water leaving a boiler.
When should an air scoop be used?
When there is no location for a boiler fitting
What is a Micro-Bubble Resorber
An advanced line scoop that are fitted with fine screens to which air bubbles adhere and travel upwards to the float-controlled air valve
What must be done to Automatic air vents during matinance?
Must be isolated from the system to avoid system shutdown or admittance of air into the system.
What are the 3 types of expansion tank?
Cushion
Diaphragm
Bladder
What type of expansion tank has an external sight glass?
Cushion
What type of expansion tank has no diaphragm or bladder
Cushion
In what orientation are diaphragm tanks installed?
Upside down
What are diaphragm expansion tanks pre charged to?
12 psi
In what orientation are bladder expansion tanks installed?
Facing up
What are bladder expansion tanks pre charged to ?
12 psi
What is the most common type of gauge?
Burdon tube
What pressure would you expect to see in a low pressure steam boiler?
15 psig
Which type of expansion tank has an external sight glass?
Cushion tank
Which component does the condensate first exit into in a high efficiency/condensating boiler?
Condensate trap.
How do you adjust the pressure setting on the pressure relief valve?
Replace it or have it adjusted by a qualified technician.
What are some signs of poor combustion?
Change in flame shape, color or sound.
How often should a float type low water cut-off be blown down?
Weekly
Who can perform the annual maintenance on a Backflow device?
Certified cross connection technician.
How often should a pressure relief valve be tested?
Every 6 months.
What should happen if there is a no flow condition when the boiler is operating?
The burners shut off to prevent damage to the boiler.
What is the purpose of a condensate neutralizer?
Reduce the acidity of the condensate
What is a way to test the operation of the float type low water cut off?
Isolate boiler
Open drain valve
Wait for low water shut off to kick in.