Burner Cycle

Sly

I recently changeded my Heat-Timer to a vision pro thermostat.  When the boiler heats up and builds pressure it builds to 5psi then cuts off.  It goes down to 2 psi and the burner kicks back on.  It does this until the temp is set at setpoint.  I do not think it did this with the Heat-Timer.  My question is how can i change it so that when it hits 5 Psi it goes to zero before it kicks back on.



thanks

sil

nicholas bonham-carter

5 psi...too high!!

i don't think the visionpro can have any effect on the short-cycling. i have the remote sensor for the visionpro mounted in a more exposed bedroom, in the upstairs apartment; so it feels the temperature up there, but is under my control.

adjust your pressuretrol way down, to cycle the boiler between  8 oz. to 24 ounces. pressures above 3 psi will convert your main vents into paperweights, and as they do most of the work of letting the air out while steam is rising, you don't want that. for more economy, get a vaporstat, and a good low-pressure gauge [gaugestore.com, 0-15 oz.].

when your main venting is inoperative, the short-cycling is exaggerated, so increasing your main vents will help that.  if your radiators, have adjustable vents, set them slow as you add more main venting, so the arrival of steam to each radiator is simultaneous.

Sly

Burner Cycle

How do i do that.  I have a Pressurol and two devices that say "Cut In"  Do i need change both of those to regulate the steam??  they are both set about the 2 psi mark.



thanks

sly

Jamie Hall

Most pressuretrols

have one scale which is "cutin" and one which is "differential" and additive.  If yours is that way, set the cutin scale to 1/2 psi and the differential to 1 psi.  Then the burner should cutout around 1.5 psi and back in around 1/2 psi.  And you system will work better.  From you description, it sounds as though it's working as it is set -- 2 psi cutin and 2 psi differential gives around 4 psi cutout.



Which, unhappily, is way too high.  As NBC noted, one can hope that your vents haven't been damaged by the high pressure -- but I'd be prepared to have to replace them.

Sly

Burner Cycle

OK.  I Will try.  However both say cutin so i guess the one to left is cut in and the other is differential.



thanks

sil

Sly

Burner Cycle

Before I change anything. This is for a small apartment building. The building is 30 feet wide by 80 feet deep. It has two floors and the boiler is in the basement. there are a total of 12 radiators in each floor. 3 in each apartment for a total of 24 in the entire building with 4 heat risers. So is 2-3 psi going to be enough to properly heat the building?

Jamie Hall

Oh yeah...

The Empire State Building heats on 1.5 psi.  I think you'll be OK...



And keep in mind that the maximum rated pressure on your vents is 3 psi -- anything -- anything -- over that runs a good chance of converting them to toast.

Sly

Burner Cycle

Thanks. I made the change. I have powerflame dual burner i need to change. Can you recommend another brand that is also dual?

thanks

sil