Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

HVACR gas heating esco Questions & 100% Verified Answers | Latest Update 2025/2026, Exams of Refrigeration and Air Conditioning

HVACR gas heating esco Questions & 100% Verified Answers | Latest Update | Already Graded A+

Typology: Exams

2024/2025

Available from 02/20/2025

tizian-kylan
tizian-kylan ๐Ÿ‡บ๐Ÿ‡ธ

2.7

(21)

3.8K documents

1 / 11

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
1 | P a g e
HVACR gas heating esco Questions & 100%
Verified Answers | Latest Update | Already
Graded A+
using an ohmmeter, there is 120 VAC between high speed and ground wires, this
indicates
๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ: open
if temperature rise is too high...
๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ: increase fan speed
how many of the 3 OSHA conditions defining confined spaces must be met
๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ: all 3
what causes the temperature limit safety switch to shut off the burner
๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ: fan motor failure
flashback indicates
๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ: the gas is flowing slower than the speed at which burn is occurring
what type of connector is used to control noise in ductwork
pf3
pf4
pf5
pf8
pf9
pfa

Partial preview of the text

Download HVACR gas heating esco Questions & 100% Verified Answers | Latest Update 2025/2026 and more Exams Refrigeration and Air Conditioning in PDF only on Docsity!

HVACR gas heating esco Questions & 100%

Verified Answers | Latest Update | Already

Graded A+

using an ohmmeter, there is 120 VAC between high speed and ground wires, this indicates ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : open if temperature rise is too high... ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : increase fan speed how many of the 3 OSHA conditions defining confined spaces must be met ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : all 3 what causes the temperature limit safety switch to shut off the burner ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : fan motor failure flashback indicates ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : the gas is flowing slower than the speed at which burn is occurring what type of connector is used to control noise in ductwork

๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : vibration eliminators if the main burner lights and after a minute the blower fan comes on but the burner flames waver in one corner... ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : there is faulty blower housing a burner orifice... ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : meters gas to the burner when lockout/tagout is used ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : there should be 1 key kept by the electrician the gas pressure is usually ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 3. a spark igniter operates at ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 7,500 vac a good thermocouple produces ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 30 millivolts what must be present for combustion

to change cubic feet per minute delivered to a single speed belt driven blower, you should adjust ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : the motor pulley size nitrogen combines with oxygen to form... ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : NOX when the burners are ignited, the blower is delayed to... ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : allow the heat exchanger to warm up gas piping must be installed with a pitch of ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 1/4 inch per 15 ft pipe joint compound should be applied to ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : the male threads, not last 2 threads if voltage is applied across 2 speed terminals on a fan motor at the same time, the motor ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : runs too fast what is the result of an oversized mid efficiency furnace

๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : the heat exchanger corrodes what draft moves flue gas through the heat exchange ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : mechanical furnace designed with the blower motor under the heat exchange is the ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : upflow a gas furnace is installed in a garage, the burners are ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 18 inches above floor a carryover on a gas burner.. ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : provides smooth lighting of all burners 100% shutoff means ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : gas to the pilot and manifold are shut off a limit switch deenergizes the ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : gas valve if it overheats what checks the pressure of a furnace ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : manometer

the volts of a hot surface igniter is ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 120 volts thermostats contain 1+ sets of contacts to control heating, they are ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : thermally actuated adjustable shutters ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : mix primary and gas 60000 btu/h operating at 50% air ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 600 cu ft vent stack temp on a natural draft furnace is ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 350 - 450 f 1/2 and 3/4 black pipe is installed, cut how many threads ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 10 - 12 a furnace with the blower motor above the heat exchanger is a ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : downflow ASHRAE specify how much CO

๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 9 ppm air mixed with natural gas is ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : primary air severity of shock is determined by ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : intensity of flow and path external static pressure is ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ :. 2 -. 6 in WC condensing furnaces work at ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 90% LP has a gravity og ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 1.5-2. pressure drop in natural gas piping is due to ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : friction or resistance a cat 4 2 pipe vent system thru roof has an elbow that ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : points down

the pilot assembly orifice is clogged ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : replace natural gas consists of ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : methane gas burners change diameter, referred to as ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : ventiru defective heat exchanger ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : inform homeowner and turn off supply of gas to furnace LP gases are ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : propane, butane flue baffle ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : increases heat exchange ignition temp of natural gas ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : 1100 - 1200

to test flame rectification ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : placemeters in series with flame sensor to test DC microamps 0 ohms b/w common and low speed wirings, winding is ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : shorted igniter in a hot surface ignition furnace doesnt energize ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : check for voltage thru pressure switch if a furnace makes a loud bang upon ignition ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : check supply to gas pressure testing resistance of a hot surface igniter ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : allow igniter to cool constant airflow, torque, and speed are types of ๐Ÿ—ธ๐Ÿ—ธ๐Ÿ—ธ : ECM motors