FIREPLACE MANUFACTURERS INCORPORATED UNVENTED NATURAL GAS LOG HEATER

TROUBLESHOOTING

Continued

OBSERVED PROBLEM

POSSIBLE CAUSE

REMEDY

One or both burners do not light after ODS/

1.

Inlet gas pressure is too low

1.

Contact local natural gas company

pilot is lit

2.

Burner orifice(s) clogged

2.

Clean burner(s) (see Cleaning and

 

 

 

 

Maintenance, page 16) or replace burner

 

 

 

 

orifice(s)

 

3.

Mislocated crossover tube

3.

Contact qualified service person

 

4.

Burner orifice(s) diameter is too small

4.

Replace burner orifice(s)

 

 

 

 

 

 

Delayed ignition of one or both burners

1.

Manifold pressure is too low

1.

Contact local natural gas company

 

2.

Burner orifice(s) clogged

2.

Clean burner(s) (see Cleaning and

 

 

 

 

Maintenance, page 16) or replace burner

 

 

 

 

orifice(s)

 

3.

Mislocated crossover tube

3.

Contact qualified service person

 

 

 

 

 

 

Burner backfiring during combustion

1.

Burner orifice is clogged or damaged

1.

Clean burner (see Cleaning and Main-

 

 

 

 

tenance, page 16) or replace burner

 

 

 

 

orifice

 

2.

Damaged burner

2.

Replace damaged burner

 

3.

Gas regulator defective

3.

Replace gas regulator

 

 

 

 

 

 

Yellow flame in front burner during burner

1.

Not enough air

1.

Check burner(s) for dirt and debris. If

combustion

 

 

 

found, clean burner(s) (see Cleaning and

 

 

 

 

Maintenance, page 16)

 

2.

Gas regulator defective

2.

Replace gas regulator

 

 

 

 

 

 

Slight smoke or odor during initial operation

1. Residues from manufacturing processes

 

and logs curing

1.Problem will stop after a few hours of operation

Heater produces a whistling noise when

1.

Turning control knob to HI position

1.

Turn control knob to LO position and

burners are lit

 

when burners are cold

 

let warm up for a minute

 

2.

Air in gas line

2.

Operate burners until air is removed

 

 

 

 

from line. Have gas line checked by lo-

 

 

 

 

cal natural gas company

 

3.

Air passageways on heater blocked

3.

Observe minimum installation clear-

 

 

 

 

ances (see pages 7 through 9)

 

4.

Dirty or partially clogged burner

4.

Clean burners (see Cleaning and Main-

 

 

orifice(s)

 

tenance, page 16) or replace burner

 

 

 

 

orifice(s)

 

 

 

 

 

Moisture/condensation noticed on windows

1.

Not enough combustion/ventilation air

1.

Refer to Air for Combustion and Venti-

 

 

 

 

lation requirements (page 4)

White powder residue forming within burner box or on adjacent walls or furniture

1.When heated, vapors from furniture pol- ish, wax, carpet cleaners, etc. turn into white powder residue

1.Turn heater off when using furniture polish, wax, carpet cleaners, or similar products

www.desatech.com

18

105070

Page 18
Image 18
Desa VFN24MV VFN30MV installation manual Maintenance