Lochinvar / Knight Boiler 80-285 Issues

up at the ceiling,

the big green thing is an expansion tank,

to the right of it I see a small red tee handle on an open drain, it's a 1/4 turn to full open, careful now,

just nudge it open and see if there is air there, a bucket is your friend,

and there is a picture of one end of your baseboard, are there any other fittings at the far end, an air valve or vent?

dirty water is better than air

basements are basements,

no air vents upstairs?

there likely aren't as that system should be purge-able

purge on the boiler screen is part of the ignition / burn / shutdown sequence, not what we're looking for,

purging air from the zone loops is playing with all your valves, a hose, and forcing water where air should not be,

you need to figure why the circ(s) aren't circing,

one must be working in that your domestic hot is working,

can you post one distant picture showing the whole deal down there, floor to ceiling, left to right,

" let me ask you this…if i were to start replacing parts, assuming something has failed, where would you start? "

check for 120v at the higher red circ, or from its controller(back of boiler) and the green one at the ceiilng also, if they have power, then the circ is bad, or jammed,

you mentioned the water was dirty, dirty water might have seized the circ(s),

the red one, isolate the circ with the valves above and below as you did earlier, on the end of the circ motor, that screw head, take it out, expect minor water, see if you can turn that shaft inside there to free it up or prove loose, put screw head back in.

may be able to do same on upper green circ,

if you don't have 120v at the circs, you have a controller or thermostat problem, did you check batteries at the stats?

kinda hard to do this from connecticut, without being there and touching,

my bet is on the middle(upper) red circ, which I believe is your primary circ getting heat to your zoning, either electrical or mechanical(seized/stuck), can't tell, or it could be air bound, as was mentioned earlier,

was the system noisy when it worked last? could you hear the water flowing last winter?

and what Homer says, these boilers like to be massaged every year or 2, but it's heating the domestic so hold off there, I do see your pressure up around 30, that's too high, 12-15 is a target, so once you re establish flow, follow up on the expansion tank and pressure,

remember to stop back and let us know

@articpenguin, what I had in mind is more than new sensors which could have been cleaned. I meant a thorough combustion chamber cleaning. I set the service lite at about 2 years in the programing. I do a thorough combustion cleaning on this boiler every 2-3 years. The dirtiest boiler that I ever cleaned was this boiler and it took me 4hrs to do the job.

do you have a wires diagram? can you post that picture(s)?

either from a panel cover or a manual

ok,

read across 3 and 4, DHW Thermostat, if you have 0v, tank is calling, if 24v, tank is satisfied, turn up aquastat, or jump 3 and 4, to make a call for domestic, you should get 120v at black and white DHW Pump,

same thing at 1 and 2, R and W, Room Thermostat Zone Control, if you have 24v there, the call for heat is not getting there(doubtful as the system pump has 120v), if 0v you have a heat call, and Boiler Pump should have 120v,

power down the boiler, take the black and white from the Boiler Pump terminals, power back on, and with 0v at 1 and 2 for call for heat, see is 120v returns to Boiler Pump terminals, if yes, replace that circ, if no 120v, you might have cooked its relay, and need a new integrated controller