This is the second Monitor 41 installed over the past 25 years. Combustion chamber was overhauled about 4 years ago. Continues to work well in all modes EXCEPT when holding temperature overnight on two burner lights. More often than not, heater turns off early in the morning with 8 burner lights flashing. Since problem is on lowest burner setting, Air Pressure SW was suspect. Hose to SW is very flexible with no cracks. Can hear contacts closing when blowing into hose lightly. Pressure switch could be on the edge of breaking contact, so operating with two burner lights went outside and blocked half of air intake - heater did not turn off. Have large fuel filter on outside tank, tank is tilted down away from outlet - haven't had water in kerosene issues. Have been vacuuming heat exchanger and blower guard even though not very dusty.
Removed hose to Pressure SW, removed air intake hose and vacuumed what appeared to be a very clean Blower. Both vent pipes clear - vacuumed anyway.
Flames in burner are bright blue on all burner settings and only see small orange flashes for a short time when firing up, and after burner settings change. No soot on window. Circulation Fan, Blower Assembly and Solenoid Pump operate quietly.
Since heater operates on 8. 6 and 4 burner lights, assume Constant Level Valve and Solenoid Pump are OK?
Could it be damper solenoid - how to test it? Could it be crap on Flame Sensor - how to test it?
Heinrich
Removed hose to Pressure SW, removed air intake hose and vacuumed what appeared to be a very clean Blower. Both vent pipes clear - vacuumed anyway.
Flames in burner are bright blue on all burner settings and only see small orange flashes for a short time when firing up, and after burner settings change. No soot on window. Circulation Fan, Blower Assembly and Solenoid Pump operate quietly.
Since heater operates on 8. 6 and 4 burner lights, assume Constant Level Valve and Solenoid Pump are OK?
Could it be damper solenoid - how to test it? Could it be crap on Flame Sensor - how to test it?
Heinrich
Comment