Free Recreation Vehicle Service Technician – Red Seal Examination Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Recreation Vehicle Service Technician – Red Seal Examination practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1A cylinder in an RV repair shop bears the WHMIS flame-over-circle pictogram. Which hazard class is identified by that pictogram?

   1. A.Flammable gas
   2. B.Oxidizing gasCorrect answer: B
   3. C.Gas under pressure
   4. D.Acute toxicity

   Explanation: CCOHS states, “The flame over circle pictogram is used for the following classes and categories: Oxidizing gases (Category 1)”. The flame, gas-cylinder and skull-and-crossbones pictograms identify the other listed hazard classes; a product may have more than one hazard, but the question asks what this particular pictogram identifies.

   Reference: WHMIS - Pictograms — What pictograms are used with WHMIS hazard classes and categories?, Flame Over Circle

2. 2An RV potable-water supply line is connected to a temporary hose submerged in nonpotable water. Local atmospheric pressure is 100 kPa absolute. At which measured line pressure would the supply be under the subatmospheric condition associated with backsiphonage?

   1. A.95 kPa absoluteCorrect answer: A
   2. B.105 kPa absolute
   3. C.110 kPa absolute
   4. D.120 kPa absolute

   Explanation: CDC defines the underlying condition as “negative or subatmospheric pressure within a water system”. CDC defines backsiphonage as backflow caused by negative or subatmospheric pressure in the water system. With local atmosphere at 100 kPa absolute, 95 kPa is 5 kPa below atmospheric pressure; each other measurement is above it. This comparison identifies a pressure condition, not proof that contamination actually occurred.

   Reference: Glossary of Definitions — Appendix A, backsiphonage

3. 3A disconnected RV DC circuit has a 4 Ω resistor and an 8 Ω resistor connected in series. What total resistance should a technician expect across the series combination?

   1. A.2.67 Ω
   2. B.4 Ω
   3. C.12 ΩCorrect answer: C
   4. D.8 Ω

   Explanation: The DOE handbook states, “The total resistance in a series circuit is equal to the sum of all the parts of that circuit”. Thus 4 Ω + 8 Ω = 12 Ω. The 2.67 Ω result applies the parallel formula, while 4 Ω and 8 Ω each omit one series resistor.

   Reference: DOE Fundamentals Handbook: Electrical Science, Volume 1 — Basic DC Theory, Basic DC Circuit Calculations, Series Resistance, p. 23

4. 4An appropriately calibrated remote monitor indicates 20% of propane's lower explosive limit in a sampled RV compartment. Using a propane LEL of 2.1% by volume, what propane concentration does that reading represent?

   1. A.0.21% by volume
   2. B.0.42% by volumeCorrect answer: B
   3. C.2.1% by volume
   4. D.20% by volume

   Explanation: OSHA states that “Combustible gas meters measure flammable gas concentration as a percentage of the LEL of the calibrated gas.” NIOSH lists propane's “Lower Explosive Limit” as “2.1%”. Thus 20% × 2.1% = 0.42% by volume. The other choices use 10% of the LEL, the full LEL, or mistake percent LEL for percent by volume. The calculation does not establish that entry is safe.

   Reference: OSHA Technical Manual, Section II, Chapter 3 — Explosibility (Combustible Gas) Sensors, Application and Principle of Operation

5. 5A technician is servicing an RV heat pump that can operate in both heating and cooling modes. Which refrigeration component changes the refrigerant flow path when the system switches modes?

   1. A.Expansion valve
   2. B.Reversing valveCorrect answer: B
   3. C.Check valve
   4. D.Relief valve

   Explanation: The U.S. Department of Energy states that “a reversing valve in the refrigeration system reverses the flow of refrigerant between the evaporator and condenser coils to switch between heating and cooling modes.” The expansion, check and relief valves have different functions.

   Reference: Heat Pump RTU Switchover Temperature Guidance — Heat pump RTU function

6. 6During an RV wall inspection, a technician wants comparative moisture readings across finished wood panels without puncturing their surfaces. Which meter type is suited to that constraint?

   1. A.A surface-contact capacitance moisture meterCorrect answer: A
   2. B.A two-pin resistance moisture meter
   3. C.A hammer-electrode resistance moisture meter
   4. D.A deep-insulated-pin resistance moisture meter

   Explanation: The NRC guide explains that capacitance moisture meters are non-destructive because “there is no need to puncture the surface,” unlike resistance-type pin meters. The other options are resistance-meter electrode arrangements that use pins penetrating the material.

   Reference: NRC: Moisture Measurement Guide for Building Envelope Applications — Section 2.5.1, Moisture Meters, p. 17

7. 7A technician examines a trailer tire that has been operated consistently above its specified inflation pressure. Which tread-wear pattern does ICBC associate with that condition?

   1. A.Faster wear in the centre of the treadCorrect answer: A
   2. B.Faster wear along both outer tread edges
   3. C.Faster wear along only the inner tread edge
   4. D.Faster wear along only the outer tread edge

   Explanation: The ICBC manual states, “Overinflating a tire causes excess wear in the centre part of its tread.” It associates wear on both outer edges with underinflation; the single-edge patterns do not describe the stated centre-wear pattern.

   Reference: Towing a Recreational Trailer Manual — Chapter 2, Wheels and tires, Tire wear, p. 7

8. 8An electric trailer breakaway system must still apply its brakes if the normal electrical cable to the tow vehicle separates. Which electrical source is intended to supply this emergency system?

   1. A.The trailer's emergency breakaway batteryCorrect answer: A
   2. B.The tow vehicle's starting battery
   3. C.The tow vehicle's trailer-light circuit
   4. D.The trailer's shore-power supply

   Explanation: ICBC says to ensure “the battery for the emergency trailer breakaway system is kept charged.” ICBC instructs owners to keep the battery for the emergency trailer breakaway system charged because a discharged battery can affect operation of the breakaway switch. The normal tow-vehicle connection can be lost in a separation, and shore power is not the dedicated emergency supply.

   Reference: Towing a Recreational Trailer Manual — Chapter 6, maintenance, Batteries, p. 48

9. 9An RV shop's respiratory protection program calls for a particulate filter suitable for oil mist over more than one shift. Which filter series has the required oil resistance, subject to the manufacturer's service-life guidance?

   1. A.N95
   2. B.R95
   3. C.N100
   4. D.P95Correct answer: D

   Explanation: CCOHS describes the “P series (Strongly resistant to oil)” as usable in atmospheres with oil particulates “for more than one shift”, subject to manufacturer service-life guidance. N filters are not oil-resistant, and R filters are limited to one shift in oil particulate.

   Reference: Respirators - Respirator Selection — What are the different classes of respirators?

10. 10An RV has been stored long enough for the water seal beneath a sink to evaporate. The customer reports holding-tank odours inside the vehicle. Which component has lost the liquid barrier that normally blocks those gases?

    1. A.Fixture P-trapCorrect answer: A
    2. B.Tank vent pipe
    3. C.Termination valve
    4. D.Air admittance valve

    Explanation: The National Research Council explains that “A trap is intended to provide passive protection from backflow of odours and sewer gases to the fixture or device protected” and that it must maintain its water seal. A dry trap has lost that barrier; the vent, termination valve and air admittance valve perform different roles.

    Reference: User's Guide – National Plumbing Code of Canada 1995 — Traps and Interceptors, 2.3.1.(1), Reason, p. 2-9