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[MarkP]

I've had problems lately with my homemade OWB steaming really bad, and using alot of water (4 or 5 gallons a day)  After posting the problem on here, and getting several replys, I made some changes to the vent pipe on Saturday per Ron's suggestion, and have been very pleased with the difference.  I also dropped my max temp. from 185* to 175*.  VERY LITTLE STEAM,,,,, until today. 

Today I looked out and saw the stove steaming ALOT, and went out to take a look, and the draft fan was running, but the temp on the gauge was 195*.   I'm not sure of the accuracy of the gauge, but the stove seemed to be overheating to the point of water spitting out the vent pipe that is over 20" tall.  I turned the blower off and within minutes, the stove was back to normal.

Bad aquastat??   It is a Honeywell L4006A 1678 with a direct imersion well, and I have the differential set at 15*. I have the aquastat insde the back cover on the stove, and it is covered with insulation.  Does it need exposed to the outside air temp to be accurate?  Are there better aquastats out there?  Does anyone use the White Rogers, or the Ranco digital temperature controller??  Can the Ranco be used in the same well as the Honeywell??

Suggestions??

[willieG]

i will guess mark...your stat is sticking but i also would like to ask if you installed a high limit switch on your home made OWB

if not...you should. mine is set for 190. it is wired in ahead of the aquastat and the blower if your stat fails or the blower stays running when the furnace temp reaches 190 the electrical power is cut to the stove and wont reset until the water temp drops to 150

your furnace will run like this untill you happen to find it too hot and investigate but you won't have a runaway fire untill your wood is gone or worse, boil your stove dry

i did have a stat go bad in my second year, installed a new one it has gone 6 years and is still acting normal

[MarkP]

Thanks Willie,,,,,,, and nope,,,,,, no high limit switch. 

Is this switch a second aquastat like I have, but with the high temp set a bit higher, and the low set at or below my original low temp?  I have an unused port on my stove close to the first aquastat I can use for this.  I figured Honeywell would be dependable, but I guess any brand can go bad.

thanks again,,,

[willieG]

the high limit switch is just a little round thing that you hook your electric hot wire too on the way to the aquastat..mine is only about 3/4 inches around and it has a flat side on it..i cut a round hole in my insulation and glued it right to my water jacket and then covered it over again. i think it just has a little piece of metal that expands and breaks the contact at the designed temp and then closes back up whenit cools to 150. i think you can by them for many different temps

i think many of the  "store bought" OWB have a "low limit switch" as well

if my photo came through, my switch is just on the end of the hot wire you see going into the middle of my stove
it is glued to the stove with a layer of cardboard around it so it wont shourt out if the wires were to come unhooked

[R W Ohio]

Mark,
If you look at the photos of our son's wood stove,the one that has the control box,the limit that I used is under the water sight glass tube.If you would like I will get you the part# from WW Grainger.The limit that I used is made to open at 190F and has to be man.reset if it opens.That way you know that there was a problem.
Ron

[R W Ohio]

Mark,

I sent you an E mail.

[atlarge54]

The little round limit switches are called snap disc limit switches. I just looked on ebay and they're fairly cheap. Fixed limit about $5-6 and variable about $20.

[MarkP]

I appreciate everyone's help. I have a limit switch ordered, and will be changing the aquastat as well.  This may save me some wood also,,,,,,,

thanks,,,

Maqrk