Energy Tech Laboratories MR212 - Manual (Page 22)

22
Burner Troubleshooting Chart
Problem Potential Cause Corrective Action
Pilot Does Not Light/Stay Lit Main gas if off Open main gas valve
Air in gas line Purge gas line
Dirt in pilot orifice Clean orifice with compressed air
Gas pressure out of range Adjust to proper gas pressure
Pilot valve is off Turn pilot valve on
Pilot orifice fitting leak Tighten pilot orifice
Excessive drafts Re-direct draft away from unit
Safety device has cut power Check limits and airflow switch
Dirty flame sensor Clean flame sensor
Remote panel in “Vent” mode Change to “Heat” mode
No spark at igniter Check wiring, sensor, and ignition
controller. Check spark gap as shown
below.
Main Burner Does Not Light
(Pilot is Lit) Defective valve Replace combination valve
Loose valve wiring Check wiring to valve
Defective pilot sensor Replace pilot sensor
Shut off valve closed Open shut off valve
Defective flame safety controller Replace flame safety controller
Pilot fails as main gas valves open
and main gas begins to flow Plug the first burner port next to the
pilot gas tube with burner cement
Not Enough Heat Main gas pressure too low Increase main gas pressure – do not
exceed 14 in. w.c. inlet pressure (5 psi.
on size 4-5 heater)
Too much airflow Decrease airflow if possible
Burner undersized Check design conditions
Gas controls not wired properly Check wiring
Thermostat setting too low Increase thermostat setting
Thermostat malfunction Check/replace thermostat
Unit locked into low fire Check wiring
Too Much Heat Defective modulating gas valve Check/replace modulating valve
Thermostat setting too high Decrease thermostat setting
Unit locked into high fire Check wiring
Thermostat wired incorrectly Check thermostat wiring
Proper Spark Gap