Psi gauge

daveamir

Hey good morning guys. I had a quick question when my steam boiler reaches 1psi it shuts itself off which is what it is set to do . However since the thermostat is not yet satisfied after about one minute of shutting off the boiler reaches 0 psi and the turns back on to satisfy the thermostat my question is, is this a long enough shut off time between turning back on or should there be a longer delay before the boiler turning back on or should I raise the cutoff cut in thank you

nicholas bonham-carter

Are you using any temperature setbacks?
Does the pressuretrol shut down the boiler before the end of the main venting phase?
How long has the boiler run before it cuts off?
How many cycles will it take to achieve the set temperature?--NBC

hvacfreak2

I want to say that this would not be such a big deal with natural gas ( atmospheric ) . Power burners and especially oil is so much more of a process to start and stop due to the moving parts and perhaps liquid fuel ( for oil ). Smarter burner controls have helped with this in the case of the latter however.

Either way you might be better off increasing the cut out pressure to allow for a longer " burner on " time , at 1 psi you have some room to play with.

SeymourCates

@daveamir

The solution to your problem is not a quick answer. The quick and dirty approach via raising the pressure limit is the method of last resort. Kindly answer the questions posed by nicholas bonham-carter so the true situation can be assessed. I might add one additional question to his list: Are the radiators fully heated all the way across when the boiler shuts down on pressure? If not, you have a venting issue that needs to be addressed.

daveamir

Thanks for the replies I keep the ThermostT at 69 at day and 67 at night I noticing this morning as the boiler was getting from 67 to 69 that it shut off. I have a big mouth on the main and it's fully hot when the boiler shuts and I replaces all my radiator vents with gorton s and my rads are all super hot when the boiler cuts off I bet the boiler runs 30 minutes before it shuts it happenes more when the temperature goes below 30 Fahrenheit

EBEBRATT-Ed

@daveamir sounds like it is working properly. Your boiler may be slightly oversized.

If it doesn't cut off on pressure during normal operation (not coming out of night setback) then I wouldn't be concerned. If it hits pressure occasionally coming out of night setback this would be normal

Jamie Hall

Oh heavens. We've been here before. So long as this is towards the end of a longish cycle, it's not a problem. All the mechanicals which people worry about are designed for tens to hundreds of thousands of cycles; if the delay on restart is being controlled by a post purge/pre purge cycle you're fine.

Do not, repeat NOT, raise the pressure of the cutout to get a longer cycle. You will waste fuel and possibly damage traps and vents.

daveamir

Thanks guys

mikeg2015

Only other solution is a duty cycle timer that will allow it to run maybe 15 minutes, then off for 5, and so on. Better is for boilers to get sized correctly, or will less pickup.

Terran

another possibility which might work would be an electronic thermostat which ramps gradually to raise the temperature after the setback.