15 TROUBLESHOOTING GUIDE

Problem

Probable Cause

Corrective Action

 

Power Supply

Check fuse and/or circuit breaker. Check voltage at

 

120/24V step-down transformer.

 

 

 

On-Off Switch

Check if On-Off switch is lighted

 

Temperature Control

Check that the operating temperature control is set

 

higher than the temperature of the water heater.

 

 

 

Flame Safeguard Control

Check for bad ground or bad control. Replace if

 

necessary.

 

 

 

Remote enable/disable open

Enable water heater or place jumper between

 

terminals R1-R2.

 

 

 

 

Check if fan connection terminals on flame control

 

 

is closed

Starting or Pre-purge

Combustion Air blower

Check for 24V at field access terminal C2. Remote

Failure

 

interlock may be open.

 

 

Fan VFD may be defective. Verify proper voltage.

 

 

Check switch contacts are closed.

 

 

Check for 24V at the N.O. side of air switch

 

Air-proving Switch

Check for 24V at the common side of air switch

 

 

Check for proper blower pressure setting – adjust if

 

 

required. Air switch may be defective.

 

Blocked Filter Switch

Check for 24V at the N.C. side of the blocked filter

 

(if equipped)

switch. Replace filter or switch as required.

 

Flame Control Pressure Switch

Check for 24V at the pressure switch terminal.

 

Loose Wire Connections

Check connections to all components

 

Power Supply

Check fuse and/or circuit breaker. Check voltage at

 

120/24V step-down transformer.

 

 

 

Flame Safeguard Control

Check for bad ground or bad control. Replace if

 

necessary.

 

 

 

 

Check amp draw during heat-up. Replace if amps

 

Hot Surface Igniter

greater than 3.1A. Check for overheating condition

 

 

due to damaged refractory around igniter.

Flame Failure

Air-proving Switch

Check if switch is bouncing. Adjust or replace.

Gas Pressure

Check for proper inlet static and dynamic gas

 

 

pressure.

 

 

 

Combustion

Inadequate flame signal may result from improper

 

combustion. Adjust to proper CO2 levels at low fire.

 

 

 

Grounding

Check for proper ground from flame control to

 

burner housing.

 

 

 

Safety Limits

Check all safety limits for fault condition and correct

 

as required.

 

 

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PV500-45U 06/12

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PVI Industries PV500-45U manual Troubleshooting Guide, Problem Probable Cause Corrective Action