Over Heat !!

Well I guess I spoke to soon. After severl days of no issues. I went downstairs cause I noticed I did not really feel any heat off the radiators. What I found was the stoker at idle and water temp of 230-240 !! with a pressure of 25PSI the main pipe was just warm to the touch. I checked aquastat it was set 160 - 180 with a Diff of 10 fire looked normal , good dead zone and nice ash length. I then shut boiler down !! I tried to get the plumber to come out but could not get hold of anyone so I went back down to see if when the power was on was the pump moving the water cause during the first check it was not !! Turned on boiler pumped kicked on and water began to move went from 235 to 160 in about 2 minutes pressure 15 PSI and everything appears to be ok . I did remove the extra pins I had put in the timer thinking I might be getting the boiler to hot,. but even at that the pump should have kicked on at 220 deg ( shouldnt it ) Has anyone had this issue before ??? is it in my pump ?? or the aquastat ??? thats all it could be right ?? the stoker was at rest so it knew enough to idle down but the pump sure didnt . will be checking it all night , wont get much sleep im sure !! It was working so good too !!


Love in Christ Jesus

Jay Williams

Don't feel bad I've seen 275 on my AA260.... not fun, the pucker factor seems to max at that point! that being said whats the draft on the stack? also how many minutes was the timer set at and changed two. I my self have a strong draft with a 8" baro damper and a stack draft of .03-.04 most of the time when the wind picks up it max's out and I still see a draft up to .2 thats when things go down hill for me. Another question tell a little more about your setup, # of zones, pump, valves, controls,

Draft was set at .02 & .01 , there has been no issue at all with draft or coal feed rate , etc... the only thing that happend was the pump was not pulling the water and I am not sure why ?? new pump , new boiler , new aquastat , yet I guess anything is possible. Once again God sent me down there to find it , every issue I have had , God has sent me downstairs to find it and prevent it. Found 2 fires and now 1 overheat !! I have checked it off and on and everything is working fine , the boiler is at rest , house is at 68 ( where i have it set ) water temp in boiler 150-160 fire great , ash great , deadzone great !! Dont understand it ???

Love in Christ Jesus

Jay Williams

jcw265 wrote:Once again God sent me down there to find it , every issue I have had , God has sent me downstairs to find it and prevent it.

Maybe Gods uneasy with that Lil bita'hellfire in the basement

overtemps can happen and it is normal to grossly overrun the aquastat settings once in awhile but the pump should operate nevertheless. I assume it was the system circulator that wasn't running. I also assume that you have a triple aquastat based on your settings description. But, there is usually also a hi limit aquastat that shuts down everything on the system after reaching a certain hi temp condition. Your overtemp should have shut down the system but usually the pump is wired outside of that circuit so that it can dump the heat on a call for heat. Check this to make sure that the pump is not wired "after" the hi limit aquastat. Otherwise, you may have a flat spot on the pump motor's rotor or a bad start capacitor and it failed to start.

I am a man of faith also but sometimes God let's us know we need to get additional help. Call that plumber.

overtemps can also occur if you are keeping too small a fire. If pick up is too slow, the stoker will build a hotter fire than needed to heat the load and the boiler will overheat. Adjust your settings to keep a physically larger mass of hot coals especially when its extremely cold outside. keep a smaller fire when it's warmer outside.

mikeandgerry wrote:overtemps can also occur if you are keeping too small a fire. If pick up is too slow, the stoker will build a hotter fire than needed to heat the load and the boiler will overheat.

Just to note this is more coomon in the spring/fall or day where you have wild temperature swings between the night and day. Depending on how you have you have the furnace set it can actually cause it to go out. What will happen is you turn the heat up in the morning... you get big a fire rolling and then it gets warm out. Furnace won't kick on for hours and goes out. Might not apply to you if it runs on the timer regardless of the temp. Probably more applicable to the EFM's or Van Wert's like my own furnace.

jcw265 wrote:What I found was the stoker at idle and water temp of 230-240 !! with a pressure of 25PSI the main pipe was just warm to the touch.

Just curious Jay,

do you have a wye strainer on the return side? an expansion tank properly sized? a hi-limit aquastat? a primary/secondary piping scheme, multiple loops off a manifold, a single loop? an asme 30psi overpressure valve?

I re-read your comments and they are disturbing because you say the pressure was at 25psi and the main pipe was just warm to the touch, i.e. not pistol-hot like the temp gauge read. When you filled your boiler initially, did you flush the system? If not, you could have a blockage at the pump impeller or elsewhere. It could be a piece of solder, tfe paste, sludge,foam or any foreign matter. If you have a strainer, shut down the system let it cool and check the strainer for blockage. Do the same for the pump or any bottle neck restriction that is accessible. If you have an expansion tank the pressure shouldn't be getting quite so high unless it is undersized. It is also possible to have an air bubble blocking movement. Check to make sure everything is bled out and that your automatic vent on the air scoop is open.

Godspeed

Richard S. wrote:Just to note this is more coomon in the spring/fall or day where you have wild temperature swings between the night and day. Depending on how you have you have the furnace set it can actually cause it to go out. What will happen is you turn the heat up in the morning... you get big a fire rolling and then it gets warm out. Furnace won't kick on for hours and goes out. Might not apply to you if it runs on the timer regardless of the temp. Probably more applicable to the EFM's or Van Wert's like my own furnace.

If his timer is set to factory specs the fire shouldn't go out. I know the overtemps you are referring to in the fall.

Also, in my case, I have either very small or very large loop sizes which can cause overheating under certain conditions of heating alternating sized calls for heat. If the boiler starts off on the low end of temperature range and the call is for heating a large zone, the boiler will be left too hot. If the subsequent call is for a small zone the zone will sometimes be satisifed off the hot boiler without firing the stoker. If the subsequent call was for a large zone off a hot boiler the boiler will be left in the proper temp range.

If I remember from a previous post, you have an L8124 aquastat. Your high limit feature did its job. What was happening is probably that the boiler would go to high limit, shut down until it cooled for 10 degrees and then start up again, as it is designed to do, except that the circulator didn't run. However, with a coal fire, the heat doesn't stop when the blower shuts off, like with oil. Till the fire dies down, the water could climb well past the high limit. This is the reason why we keep a 50 degree spread with the efm stoker boiler to prevent outfires.

I would suspect a faulty aquastat, with no power or occasional power to C1. I get them once in awhile for warranty replacement.

I would not worry about the overtemp doing any damage. I routinely see 260* or more on mine at times when idle.

I did bleed system on the intial install , started with bottom worked way up then bleed bottom again. It has been working fine ever since I turned it back on last night. Temp is riding 150 -170 range with my aquastat set at 160 -180 with the differ set on 10. fire is proper size and has been. The stoker is running less due to the recovery temp has become more stable. The high temp switch I think is set to 250 deg per keystoker. However the aquastat should have kicked on at 180 based on my setting but if nothing else 220 deg. This did not occur. !! When the pump did kick on the main pipe became very warm indeed ( 235 deg water ) the system cooled down to 160 within a minute or so. along with pressure around 15PSI . This has not c hanged ,. House is at 68deg ( per my T-stat setting ) boiler temp is within my aquastat settings, . Also after I thanked God for taking care of me as he always does , I then did call plumber !! They are telling me if its not doing it now , what can they check ?? my question is to all of you ( what can they check ) ?? Also if it were to hit th e 250 deg mark and or the 30psi mark what happens ??? should I be worried ??? what are the procedures for something like that !!

Love in Christ Jesus

Jay Williams

If it happens again, turn the thermostat all the way up and after a few minutes, check for voltage at C1. If you have none, you have a bad relay (zone valve ?) or bad aquastat.

jcw265 wrote: The stoker is running less due to the recovery temp has become more stable. The high temp switch I think is set to 250 deg per keystoker. However the aquastat should have kicked on at 180 based on my setting but if nothing else 220 deg. This did not occur. !! When the pump did kick on the main pipe became very warm indeed ( 235 deg water ) the system cooled down to 160 within a minute or so. along with pressure around 15PSI . This has not c hanged ,. House is at 68deg ( per my T-stat setting ) boiler temp is within my aquastat settings, . Also after I thanked God for taking care of me as he always does , I then did call plumber !! They are telling me if its not doing it now , what can they check ?? my question is to all of you ( what can they check ) ?? Also if it were to hit th e 250 deg mark and or the 30psi mark what happens ??? should I be worried ??? what are the procedures for something like that !!

Love in Christ Jesus

Jay Williams

Assuming your hi limit aquastat and relief valve are new and hooked up properly, they will avert explosion of the boiler vessel if that is your primary concern.

What a good plumber will check is all of the electrical connections on the controls, the controls, and the strainers. Stoker man was pointing out that the c1 on the anthrastat can be monitored with a meter to see if juice is flowing to the circulator on a call for heat. The plumber should check all of those control connections.

I was worried there was a blockage in your piping because you had a hot boiler and cool boiler pipes. Unless you have a flow check valve, the primary loop or boiler piping will experience gravity flow or convection and heat up the boiler piping (not your room loops). If it was hot on the boiler side of the circulator but not on the other, and it had a flow check built into the circulator, the circulator isn't doing any pumping due to 1) bad relay or connection 2) blockage 3) bad circulator motor/broken impeller.

Continue your prayer, as I will, and call a different plumber.

I have mine set so if I hit my high limit 2 of my zones will open and the circulators for the zones will run dumping the heat . It overrides my thermostat on my rooms . With my keystoker I have not seen this happen yet, but a few times when the weather was warm with my old wood boiler the house was in the 80s . Dave