2 flashes wont light
Heater has been working for 2 months fine. Today won't start. LED flasing 2 flashes. When it was woking your could hear the ignition snapping to light now you don't hear that and it won't light. Tried cycling the power same result. Ignitor or board? How do you test?
Heating & Cooling - Mr. Heater - MHU45NG
Answers & Comments
SOUNDS LIKE A PRESSURE SWITCH MALFUNCTION OR A OBSTRUCTED FLUE EXHAUST. 2 FLASHES MEANS YOU ARE IN SYSTEM LOCKOUT. ATTEMPT TO START 3 TIMES THEN IN LOCKOUT MODE RIGHT? YOU WILL NEED TO TURN OFF AT T-STAT OR BREAKER TO RE-SET UNIT, OR WAIT 60 MINUTES & IT WILL DO IT AUTOMATICALLY. WHEN IT CALLS FOR HEAT THE DRAFT INDUCER MOTOR WILL COME ON, THIS WILL CREATE A VACCUM THAT OPENS THE PRESSURE SWITCH PROVING DRAFT INDUCER IS VENTING, THE VACCUM CREATED CAUSES THE PRESSURE SWITCH TO OPEN PROVIDING POWER TO THE IGNITION CONTROL. THIS IS WHERE YOUR PROBLEM IS ACCORDING TO YOUR DISCRIPTION. TRY TO DISCONNECT VACCUM LINE FROM DRAFT INDUCER MOTOR & SUCK ON IT WHILE LISTENING FOR A CLICKING SOUND AT PRESSURE SWITCH. IF YOU DON\'T HEAR THE CLICKING SOUND WHEN YOU DO THIS, THEN YOU NEED TO REPLACE THE PRESSURE SWITCH. IF YOU DO HEAR THE CLICKING SOUND THE PROBLEM IS WITH AN OBSTRUCTION IN THE FLUE VENTING. THIS IS SOMETIMES CAUSED BY DEBRIS GETTING LODGED IN THE PORT AT INDUCER MOTOR WHERE THE VACCUM LINE FROM PRESSURE SWITCH IS CONNECTED. TRY TO CLEAR OBSTRUCTION WITH COMPRESSED AIR OR A WIRE HANGER. THIS SHOULD FIX YOUR PROBLEM. GOOD LUCK. HOPE THIS WAS HELPFUL.