Boiler Short Cycling

Xrrider_280

I have a Weil McClain CGi 4 With a Taco 007-F5 circulation pump. When calling for heat, my flame cycle runs for about 2 minutes and cuts out. It goes longer if more than one zone is calling for heat, but never more than five minutes. I can sit and watch the digital temp display on the control board. The flame will start at 160 F and kick off at 180 F. The circulation pump sounds like it's running but it is very quiet. If I put my ear right to it, it sounds like like it is moving water, but very hard to tell. My return lines are very hot. It's currently 10 F outside and the house does not hold heat well so the boiler runs almost constantly. Is this normal operation or does it seem like there is a problem. The manual is unclear on if I can turn the temperature differential between on and off temps up. The temperature knob is right in the center, economy knob to max.

Xrrider_280

I wanted to add that there is a very slight "air in the pipes sound". I bled the entire system last spring due to a large amount of banging or as I call it "air in the pipes sound". Since then the noise has been minimal.

hot_rod

Unfortunately that is a common occurrence with zoned systems on boilers the cannot modulate.

Often times the boiler is oversized for the home which makes the short cycling more pronounced.

You can tweak some settings on the control sometimes to help.

More permanent solutions are combining zones, adding a buffer tank, installing a modulating, more efficient boiler.

You could do some number crunching, measure all the fin tube or radiators to see what their output is.

Perform a heat load calculation to see what the home in it's current condition requires.., is always a good first step. It is the map to an appropriate system.

This is a very common question here on HH.

There should be an air purger at the boiler to get the last remaining air expelled after the manual bleeding?

HVACNUT

Giving 25 BTU's per square foot, that boiler could heat a 3,000 square ft home with its 76K BTU output.

What Series boiler is it? Does it have an Economy dial? If so, turn it to Max. That will hold off the burners to see if the current water temperature is enough to satisfy the thermostat. If you find the Max setting isn't keeping up with demand, turn it down a bit. Like @hot_rod said, there's only so much you can do without spending $$ to save $. Next boiler boiler go for the CGi-3.

RascalOrnery

Is it unreasonable to suggest manually setting the high limit to something with a wide differential like 150-190?

Or adjusting the cycles per hour or the anticipator on the thermostat?

Does this boiler provide domestic hot water via a coil or indirect?

I am rather confused why some oil burners have so little water mass and then are tied into multi zone systems.

EBEBRATT-Ed

Buffer tank would be the fix. I would widen the differential on the control if possible