Hydronic Heating Fundamentals Flashcards
A conventional boiler is designed and should maintain an operational water temperature of ____.
140 degrees F
A dry-base boiler is dry in the ____.
area under the combustion chamber
Boilers that are lighter and classified as low-mass, low-volume are generally made of ____.
copper
One way to prevent corrosion is to add ____ to the water, which interact chemically with contaminates, rendering them inert.
chemical scavengers
Another way to prevent corrosion is to add ____ to the water, which adds a protective coating to the surface of the metal.
corrosion inhibitors
The proper pH range for water in a hydronic heating system is ____.
between 7 and 10
Balancing valves are most often ____ valves.
globe or ball
Heat exchangers that transfer heat from the circulating water in a hydronic system to the air in a conditioned space are called ____.
terminal units
The type of air that consists of small air bubbles that travel along with the circulating water is called ____.
entrained air
The type of air that consists of bubbles at the high points of the hydronic system is called ____.
free air
A boiler indoor reset control is used to adjust ____.
boiler temperature to match the heating load
Blockage in the intake and exhaust passages can cause ___.
incomplete combustion
A safety control that shuts down the boiler if the burner flames travel beyond the combustion chamber is a ____.
rollout switch
A safety control that shuts down the boiler if a backdraft condition is detected is a ____.
blocked-vent switch
The cause of most water circulation problems in a hydronic heating system is ____.
air trapped in the system
