A furnace's certified installation instructions say the gas supply piping must be supported outside the furnace cabinet. What is that support mainly protecting?

the gas valve, manifold and burners from the pipe's weight

the drip pocket from overfilling with condensate

the pipe's electrical bonding path to the building's ground

the cabinet's side panels, near the burners, from heat

During a furnace replacement under direct supervision, a G.3 threads a new 1/2 in. nipple into the inlet of the combination gas control. How is the control held while the nipple is tightened?

with a second wrench on the flats at the control's inlet end

with a pipe wrench gripped around the middle of the control body

by hand on the solenoid housing, which gives the best leverage

it needs no holding, since it is fixed to the burner manifold

A corded hammer drill that is not double insulated is found with the grounding prong broken off its plug. What should be done with it?

take it out of service until a grounding plug is fitted

fit a new two-prong plug and return it to service

use it, since the GFCI on the circuit replaces the ground

use it only for short jobs on dry floors

One leg of a U-tube manometer is connected to the test port in an operating water heater's vent connector, and the other leg is open to the basement. The liquid rises in the connected leg and falls in the open leg. What does the reading show?

the vent pressure is below the basement's pressure

the manometer was not zeroed before it was connected

the vent pressure is above the basement's pressure

the vent and the basement are at the same pressure

A G.3 has just measured a blower motor's current with the multimeter's red lead in its 10 A jack. He turns the dial to AC volts to check the 120 V at the service switch. What must he do before touching the probes to the terminals?

move the red lead from the 10 A jack to the volts jack

nothing more, as the dial alone selects the volts circuit

set the dial to its highest amps range first

swap the red and black leads between the jacks

TSSA G3 Module 2 Practice Questions: Fasteners & Tools

Five free practice questions on fasteners, tools and instruments: module 2 of the nine modules of Ontario's Gas Technician 3 (G3) certificate exam, which TSSA runs. The exam is all multiple choice; these have four options and one correct answer, as every question in our bank does. Answer each one before opening the explanation. No account, no email.

01The questions

Recall · Pipe and tubing supports and electrical fasteners

A furnace's certified installation instructions say the gas supply piping must be supported outside the furnace cabinet. What is that support mainly protecting?
1. the drip pocket from overfilling with condensate
2. the pipe's electrical bonding path to the building's ground
3. the cabinet's side panels, near the burners, from heat
4. the gas valve, manifold and burners from the pipe's weight
Show the answer

D. Correct. Manufacturers require the piping to be carried by its own supports so its weight does not bend or distort the burner rack, manifold or gas control inside the cabinet; a strained control or manifold can leak or misalign the burners. Strap the pipe to the structure close to the drop.

Why not the others

A. A drip pocket collects moisture and debris whether or not the pipe is strapped; supports do not change how much it holds. The support keeps the piping's weight off the gas control and manifold.

B. Supports are mechanical, not electrical; a strap on a joist is not a bonding path, and bonding is not what the instruction addresses. The supports keep the piping's weight off the gas control, manifold and burners.

C. Supporting the pipe outside the cabinet has nothing to do with heat on the panels, which the appliance is built to handle. The instruction keeps the piping's weight off the gas control, manifold and burner rack.
Procedural · Selecting hand tools by application, size, material and operating range

During a furnace replacement under direct supervision, a G.3 threads a new 1/2 in. nipple into the inlet of the combination gas control. How is the control held while the nipple is tightened?
1. with a pipe wrench gripped around the middle of the control body
2. with a second wrench on the flats at the control's inlet end
3. by hand on the solenoid housing, which gives the best leverage
4. it needs no holding, since it is fixed to the burner manifold
Show the answer

B. Correct. Control makers allow a wrench only on the casting flats at the inlet and outlet ends, and furnace instructions call for a back-up wrench at the gas control so it does not turn. Holding the end being threaded keeps the twisting force out of the control body and off the manifold.

Why not the others

A. Gripping the middle of the body puts the full tightening torque through the casting and can distort or crack it, and pipe-wrench teeth damage the body. The back-up wrench goes on the flats at the end being threaded.

C. Makers warn against using the solenoid or operator as a lever: it is not built to take torque and can be damaged. Hold the control with a wrench on the flats at the inlet end instead.

D. Being mounted on the manifold is exactly why it needs holding: unsupported, the torque on the nipple turns the control and strains the manifold joint. Furnace instructions call for a back-up wrench on the gas control.
Procedural · Electrical safety of portable power tools: double insulation, grounding, ground-fault protection, cords

A corded hammer drill that is not double insulated is found with the grounding prong broken off its plug. What should be done with it?
1. take it out of service until a grounding plug is fitted
2. fit a new two-prong plug and return it to service
3. use it, since the GFCI on the circuit replaces the ground
4. use it only for short jobs on dry floors
Show the answer

A. Correct. On a tool that is not double insulated, the grounding conductor and third prong carry fault current from a live metal housing back to trip the circuit protection; without them the housing can stay live. A broken three-prong plug is replaced, and the tool's grounding is checked before it is used again.

Why not the others

B. A two-prong plug suits only a double-insulated tool. On this drill it leaves the metal housing with no ground path at all, so a fault could leave it live. The tool stays out of service until a proper three-prong grounding plug is fitted and its grounding is checked.

C. A GFCI is added protection that trips on leakage; it does not restore the equipment ground the third prong provides, and safety guidance is never to break off or do without that prong. Replace the plug before using the tool.

D. Dry floors and short jobs lower the chance of a shock but not the hazard of a housing that can become live with no ground path. Replace the plug before further use.
Recall · Pressure instruments: U-tube and digital manometers and gauges; reading inches of water column and psig

One leg of a U-tube manometer is connected to the test port in an operating water heater's vent connector, and the other leg is open to the basement. The liquid rises in the connected leg and falls in the open leg. What does the reading show?
1. the manometer was not zeroed before it was connected
2. the vent pressure is above the basement's pressure
3. the vent pressure is below the basement's pressure
4. the vent and the basement are at the same pressure
Show the answer

C. Correct. Liquid moves toward the lower pressure: when the connected leg rises and the open leg falls, the vent is below room pressure, a negative reading (a draft). Its size is still the full difference between the two surfaces.

Why not the others

A. Zeroing sets the starting level; it cannot make one leg rise and the other fall. Opposite movement of the legs is a pressure difference, here the vent below room pressure.

B. Pressure above room pressure would push the liquid down in the connected leg and up in the open leg, the opposite of what is seen. A rise in the connected leg means the vent is below room pressure.

D. Equal pressures leave both surfaces level at zero. A rise in one leg and a fall in the other shows a difference, and a rise on the connected side shows the vent is below room pressure.
Procedural · Meter safety: category ratings, lead condition, proving the tester before and after use

A G.3 has just measured a blower motor's current with the multimeter's red lead in its 10 A jack. He turns the dial to AC volts to check the 120 V at the service switch. What must he do before touching the probes to the terminals?
1. nothing more, as the dial alone selects the volts circuit
2. set the dial to its highest amps range first
3. move the red lead from the 10 A jack to the volts jack
4. swap the red and black leads between the jacks
Show the answer

C. Correct. With the red lead in a current jack the meter's input is a low-resistance shunt, whatever the dial says; across 120 V it becomes a short circuit through the meter, blowing its fuse and risking an arc at the probes. Meter makers warn never to measure voltage with a lead in an A or mA jack: move it to the V jack first.

Why not the others

A. The jacks, not just the dial, decide which circuit inside the meter the probes connect to. A lead left in the current jack puts a near short across the 120 V supply. Move the red lead to the volts jack.

B. Any amps range is a near short circuit when placed across a voltage. The red lead goes back to the volts jack and the dial to AC volts before measuring.

D. Swapping the leads still leaves one in a current jack, a near short across the supply. The red lead belongs in the volts jack and the black in COM.

02Answer key

Question	Answer	Learning outcome
Q1	D	Pipe and tubing supports and electrical fasteners
Q2	B	Selecting hand tools by application, size, material and operating range
Q3	A	Electrical safety of portable power tools: double insulation, grounding, ground-fault protection, cords
Q4	C	Pressure instruments: U-tube and digital manometers and gauges; reading inches of water column and psig
Q5	C	Meter safety: category ratings, lead condition, proving the tester before and after use

03What module 2 covers

The fasteners, tools and instruments a gas technician works with: identifying fasteners and choosing anchors for wood, masonry, concrete and steel, pipe and tubing supports, corrosion between dissimilar metals, selecting, using and caring for hand tools and power tools, the electrical safety of portable tools, and the measuring, pressure, combustion-testing and electrical instruments used on gas appliances, with how to use each one safely.

TSSA names module 2 “Fasteners, Hand Tools and Power Tools”. It gives its G3 curriculum only to accredited training providers, so the five objectives below are TicketPrep's own, built from public sources such as college course outlines and Ontario's regulations, not TSSA's. TSSA does not publish the G3 question count or how many exam questions come from each module: its prep guide gives no G3 count and no per-module count, and candidates who fail get a mastery report broken down by module. The right-hand column is how many questions our bank holds on each objective, Standard and Advanced together, not a count from the exam.

Our objective	In our bank
Objective 2.1 Identify, select and handle fasteners and anchors	7
Objective 2.2 Select, use and care for hand tools	5
Objective 2.3 Select and use power tools and accessories safely	4
Objective 2.4 Select and use measuring, pressure and combustion testing instruments	8
Objective 2.5 Select and use electrical testing instruments safely	4

04What the questions turn on

Supports are chosen for the load and the metal

An anchor's working load is its rated pull-out strength divided by the maker's safety factor, and the number of anchors is rounded up. Straps must suit the tubing: copper-plated straps on aluminum tubing in a damp basement make the aluminum corrode where they touch. On a light-gauge steel stud, a self-drilling screw rated for the stud's gauge fastens a strap in one pass.

The right wrench, used the right way

A flare-nut wrench seats on five of the six flats, so a soft brass nut does not round off. A pipe wrench grips best with a gap between the pipe and the back of its hook jaw. When a pipe wrench is too small to break a joint loose, the safe step is a larger wrench, not a pipe slipped over the handle.

A manometer reads between its two surfaces

On a U-tube manometer the reading is the full height between the two liquid surfaces: the fall in one leg plus the rise in the other, even when the legs move unequally. With one leg on each of two taps, it shows only the difference between them; each pressure on its own is read with the other leg open to the room.

Zero in fresh air; prove the tester

An analyzer or gas detector that zeroes itself at start-up takes whatever is in the air as zero, so if it is switched on in a room with CO or gas, every later reading is low. Makers say to switch on in fresh air. A non-contact tester only screens for voltage; a circuit is proved dead with a two-pole tester checked on a live source before and after the test.

05The other modules

The G3 exam covers nine modules, 1 to 9. Each has its own page of free questions:

The TSSA G3 practice test page describes the full question bank. How these questions are written and checked: how our questions are made. Found a mistake? Tell us and we will fix it.