NSS Installation and Setup Procedures 2

Question 1

What is the minimum required clearance above a Navien tankless water heater for service access?

Accepted Answer

18 inches

Answer

Navien requires a minimum of 18 inches of clearance above the unit to allow proper service and maintenance access.

Question 2

When installing a Navien NR or NRC series unit, which gas valve setting must be confirmed before startup?

Accepted Answer

Gas type (natural gas or propane) is set correctly on the gas valve

Answer

The gas type selector on the valve must match the supply gas (NG or LP) before startup to ensure proper combustion.

Question 3

Which type of venting material is approved for use with Navien condensing tankless water heaters?

Accepted Answer

Schedule 40 PVC or CPVC

Answer

Navien condensing units produce low-temperature flue gases and require PVC or CPVC venting rated for the application.

Question 4

During a Navien unit installation, the recirculation pump is wired to which terminal block?

Accepted Answer

CIRC terminals on the PCB

Answer

The internal or external recirculation pump connects to the CIRC terminals on the Navien PCB for integrated control.

Question 5

What is the maximum allowable gas supply pressure for a Navien natural gas tankless water heater at the unit's inlet?

Accepted Answer

10.5 inches W.C.

Answer

Navien natural gas units have a maximum inlet gas pressure of 10.5 inches W.C.; exceeding this can damage the gas valve.

(NSS) Certified Navien Service Specialists Practice Test