cant figure this one out

Weezbo

boiler brushed recently or fuel delivered in previous 3 days?could be some water molecules chillin it out.squirrle cage blower fans clean? take small tooth brush to them...

Michal_2

i can not figure this one out

Well i have a burnham with a carlin burner and a webster pump, saturday it shut off on safety and the burner motor was off on thermal overload, so i reset both, and she fired right up, i watched it all day, fine, next morning same thing, checked the pump, all pressure and vacuum is fine. changed the motor, had a spare, well guess what, did the same thing. so changed the pump, had a spare and still doing the same thing, so now i am back to the original motor and a new pump, and this morning it did it again, does anyone have a idea whats going on, all parts move freely. So any ideas, i thought maybe the aquastat was not sending enough current down, but seems fine on the meter

Fred Harwood

tough one

Motor overheat can be a function of the fan spacing, which space allows for motor cooling air. Check the specs on spacing. Also check for low supply voltage, especially during the night.

How long is your cycle?

Michal_2

i did all service, fueal oil is clean, cad cell is good, no water in tank or oil, tanks indoors. I spaced the blades as per specs, but that was a good idea, will check spacing specs again

Weezbo

maybe check cadd for OHMs or loose scocket connection

Al Gregory

81814g is chattering when your not there more than likely. I see it three or four times a year where the motor goes off on overload because the relay is going on & Off very fast at start up. Change the cadsell control. Old RobertShaw controls were also known for causing motor overloads also

Michal_2

WELL, WERE GOING THE WRONG WAY NOW, i KNOW THE CADD CELL IS GOOD, WHEN I HAVE A FLAME WERE GREAT, AND THE CAD CELL IS DOING ITS JOB BUT THE BURNER MOTOR SHUTS OFF ON THERMAL OVERLOAD, BUT ALL PARTS MOVE FINE, I WILL CHECK THE SPACING OF THE SQUIRREL CAGE FOR CLEARENCES, POSSIBLY NOT ENOUGH AIR IS SUCKING PAST THE BRUSHES.

TGO_54

Try putting

an amp probe on the burner motor to check the current draw. See if it increases as the burner runs. Check fuel lines (supply and return if there is one) for restrictions.
Good Luck

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

m dewolfe

overload

Is this a 2 line fuel system or a single line? is the tank inside or out? If you have replaced the pump and the motor and it continues to trip out on the THERMAL overload I would look for an obstruction in the fuel system. Another thing to try would be to trip the primary while the burner is running and see if the motor goes out on overload...not too likely but still posible. Could you leave your amprobe on the motor with the peak hold function and see just how high the current goes?.....

EBEBRATT_4

Have you ever found the motor to be hot?? Check motor amps
and wiring all the way through. Obviously tripping on overload means the motor is getting hot-is insulation missing on inside of boiler mounting plate overheating the motor? Run the motor on a long cycle-if the motor is not hotter than it should be it is probably failing to start. What is the ambient temperature of the equipment room-is it very hot?.

Al Gregory

I have seen it many times when the cadsell control chatters the motor will go off on overload. Either the control is no good or there is a low voltage problem