Heat Pumps and Electric Heat
How do heat pumps change direction
powering the reversing valve
The exhaust temperature of a condensing gas furnace is
90-135
: A blow down also known as a bleed is defined as the evaporation of water system for a cooling tower
relieves the concentration of sediment in the sump
The unit for flow of electricity is the
ampere
The color for an oxygen hose is.
green
A heat pump system is stuck in cooling because there are 24 volts applied to the reversing coil at all times the problem is probably a
miswired control circuit
Give the reason should you wait at least 5 minutes before relighting a gas furnace
to allow gas to clear out from the surrounding area of the unit
This device or control maintains water temperature in a boiler
aquastat
Heating elements in a magnetic starter are used to
protect the motor from overloads
The proper flux for soldering tin is.
zine chloride
The standard amount of air movement through the indoor coil of a heat pump unit is.
450 CFM
The purpose of a draft hood on a gas fired flue stack is to
prevents back draft, provides for escape of gas, and neutralizes stack action
The limit control for the hot water system is known as the
aquastat
An HVAC system may be controlled by
thermostat
pressure control
The melting temperature of 50/50 solder is this degrees
400
The component that should not operate during the defrost cycle of a heat pump unit is.
outdoor fan
The draft hood prevents
flame from extinguishing
A hydronic zone control valve is actuated by the
thermostat
Complete this HVAC statement: A direct drive motor requires.
requires no belt
Tinning a soldering copper tip means coating with
solder
When a heat pump is in the defrost cycle
the outside coil is the evaporator and is being defrosted
According to manufacturers, the service technician should wait 5 minutes before relighting gas heating units in order to allow.
gas to escape the burner compartment
This is the purpose of an expansion tank in a hydronic heating system
to absorb expanding fluids
to limit pressure in system
On a continuous basis a fuse will hold blank of its rating
80%
When using oxyacetylene welding equipment you should
use a striker when lighting the torch
keep the gas lines away from the work
wear safety and dark glasses