NSS Combustion and Venting Systems 2

Question 1

Which Navien error code typically indicates a blocked flue or exhaust condition?

Accepted Answer

E048

Answer

E003

Answer

E012

Answer

E033

Question 2

What type of sealant must be used to join PVC vent pipes in a Navien installation?

Accepted Answer

Listed PVC primer and solvent cement

Answer

High-temperature RTV silicone

Answer

Pipe thread seal tape

Answer

High-temperature furnace cement

Question 3

What is the primary function of the condensate trap on a Navien condensing unit?

Accepted Answer

Maintain a water seal to prevent flue gas from escaping through the drain

Answer

Filter particulates from flue gases

Answer

Measure flue gas temperature for diagnostics

Answer

Neutralize condensate pH before it reaches the drain

Question 4

What is the minimum clearance required between a Navien horizontal vent termination and the ground or anticipated snow level?

Accepted Answer

12 inches

Answer

6 inches

Answer

18 inches

Answer

24 inches

Question 5

What is the maximum equivalent vent length typically permitted for a Navien NPE series unit using 2-inch PVC pipe?

Accepted Answer

60 feet

Answer

30 feet

Answer

90 feet

Answer

120 feet

Question 6

What should a technician inspect first when a Navien unit displays error code E003 (ignition failure)?

Accepted Answer

Gas supply pressure and igniter condition

Answer

Condensate drain line for blockage

Answer

Incoming cold water temperature sensor

Answer

Exhaust vent pipe for obstructions

Question 7

What is the approved minimum clearance between a Navien vent terminal and a gas meter or gas pressure regulator?

Accepted Answer

3 feet

Answer

4 feet

Answer

6 feet

Answer

10 feet