問題一覧
1
A component that appears in the 70 furnace but not a 90% furnace
draft diverter
2
3 types of furnaces
upflow downflow horizontal
3
An induced draft fan would be on a 70% furnace true or false
False
4
Can a fan realy control a blower motor
yes a relay can as well as a fan relay IFC
5
Four components required for a furnace
limit switch thermostat fan switch Contactor
6
On a 90% furnace which portion of the exhaust gases condense
secondary heat exchanger
7
What material should the venting of a 70% furnace be made of
metal single wall
8
A device that Can reduce capacity of induced draft fan on a smaller furnace
restrictor plate
9
What are the components gas flows through?
gas valve manifold spud burner
10
Another term for exhaust
flue pipe
11
What does the flue pipe Connect to
chimney or outside
12
A heat anticipator can be adjusted to prevent
thermostat overshoot
13
Which of the following three is? Measurement current flow
amps
14
Which component forces air thought the heat exchanger inside the venting
induced draft fan
15
Does a fan switch open or close when the furnace is hot
Close when it’s hot open when it’s cool down
16
What would the jumper wire in the com/fan be removed
The jumper will be removed when wire to 24 V
17
A transformer that uses 120v in the primary and 24v in secondary
step down transformer
18
To adjust the speed on a Direct drive blower what device will be adjusted?
relay
19
What are the components of a fan center?
relay transformer junction box
20
What type of furnace produce water
90% or plus
21
What does a 90% furnace require for condensation?
collector box and drain line
22
Where does combustion take place on a 90%?
Primary heat exchanger
23
What kind of limit switch it’s inside a blower motor
auxiliary limit switch
24
What is the limit Switch used for
to prevent extensive heat
25
What is the rollout switch for?
release heat out the heat exchanger
26
What two pipes does a 90% efficiently furnace have
intake pipe exhaust pipe
27
N/A
N/a
28
N/a
N/a
29
N/a
n/a
30
What type of pipe is bi vent
double wall pipe
31
What does IFC control
Fan and ignition controls
32
How do you pinch a flue pipe
upward pitch
33
Identify the switches
temperature switch on rise and pressure switch open on the rise capacitor coil transformer
34
The part under the thermostat cover
The subbase
35
What is the Y wire?
blue for cooling
36
Is low-voltage such as 24V consider central voltage TRUE OR FLASE
true
37
12 or red wire 24v is connected to what
transformer secondary
38
What causes the open rollout switch
crack in the heat exchanger
39
Where is a vent safety switch located on a 70% furnace
draft diverter