How to use water heater thermostat?

[patandchickens]

Quote:
The thermostat ought to go near the eggs. If you put it in a separate chamber where the lightbulb is, you will have a harder time maintaining a steady temperature.

Pat

 

[McHenry1947]

I like this real well http://www.dpdigitalcontrol.com/products.html about a degree swing 99.8 to 100.9 and you don't have to do any modification. Plug your heat source into it and set temp. I have a 200w bulb that runs about 30 seconds and off about the same, in a 2 ft. X 2 ft. X 3 ft. tall 2 shelves, I am using 2 pc fans and 1 1/2" pvc for conduit into dead air space in bottom with holes to disperse heat into egg space. This is my first try and for now it is working great, keeping my fingers crossed that it don't fail.

Keith

 

[Penturner]

Keith, I saw this in another post the other day. one more component to toy with. For now I am not really looking for better or worse components, I am looking for sure fire ways that anyone can make any component work. In a nut shell I see lots of people using Thermostat X,Y,or Z but getting very random results. I also notice that most directions just say "I used a (insert your choice here) thermostat". Like they just dropped everything into the bottom of the box and it all started working. Not even close to that easy at least with the water heater stat.
Her is an example of what I finally figured out to this point concerning the water heater thermostat.
mount your lamp in the location of your choice (I will experiment with this in time as well) then mount the Water Heater Thermostat so that the metal back plate is toward the lamp and about 1 inch away from the bulb. (I have mine laying sideways but you can try having it over the top of the bulb as well) this will cause the thermostat to cycle fast enough to keep the temperature at 1 tenth of a degree. adjust stat to increase or decrease temperature.

I have tried these other placements. Stat simply wired and place across the chamber from lamp. Result was a 10 degree temperature swing.
Drilling holes in the front of thermostat housing to admit more air to plate in an attempt to lower cycle time. (A cycle is the time it takes the stat to turn on until it shuts off and turns on again. from on to on is 1 cycle) Lowering the cycle lowers the temperature fluctuation. Result, destroyed on stat, second stat reduced temperature fluctuation from 10 degrees to 4 degrees.

Placing stat very close to lamp but not with back to lamp. temperature fluctuation reduced to 2 degrees.

placed stat so that back was less than 1 inch from lamp, cycle time fell to less than 3 minutes and no measurable temperature fluctuation..
I am waiting for the incubator to get back up to a level temperature after having built the block that holds the stat in place in front of the lamp but it is still cycling at a rate of about 2.5 minutes. and the digital thermometer has been on a steady climb. I know from all my other work that a 2.5 minute cycle does not allow the temperature to fall even 1 tenth of a degree though.

I also plan to pipe the warmed air to the floor of the incubator from the outside. The floor will be like an air hockey table. In that case I want a chamber that warms the air to 99.5 degrees that can then be blown into the incubator. lots of experimenting yet to do. i am excited about getting the WH Stat dialed in to a tenth of a degree though. now to get it on the 99.5 tenth of a degree.

 

[McHenry1947]

I understand what you are saying. You could be a lot like I was at one time, I had to know how it worked and what made it work, and I always thought I could do it better my way. Sometime I did and sometime not but it is the challenge. It is the satisfaction of doing something yourself and making it work like you want it to. I still think your thermostat will have to be in the bator-egg compartment or the temp will be inconsistent. But it sure is fun to work it out for your self. When it works and you hatch in it it will be more fun....

Keith

 

[ksf59]

Penturner , you will get it figured out. I have built 2 homeades in the last 7 weeks. Used water heater stats. My first attemp hatched eggs and is locked down right now. My second attemp is full and on about day 7. I like my second bator better and will redo my first when it empty. The water heater stat works fine if you under stand how they work. the metal part is placed on a water tank and respond to heat. I place my metal part of my stat above the light bulb about 3/4 of an inch. That will get you a pretty fast response time. I used a little diff. model for my second bator and place my light in a different postion. My first bator keeps temp very well, and heats on for about 30 to 40 seconds and off for 2 minutes or so. May have a 1/2 degree temp swing. My second bator is set up with the light on the middle of the long side of the bator . My first it is one the end. Both have the heat sourse at the top.it cyles on for 15 seconds off for 45 second to a minute. The temp once stable from placing eggs has not varied . Is has a high of 99.5 and a low of 99.5 measued in 4 locations of the bator. They each have 1 fan, placed in the middle of the top, blowing up, and placed 1/2 inch from the top of the bator. Air flow is good, and I have a smaller fan in the smaller bator. I use 40 watt bulbs in both and am happy with both at this point. I am going to build a cabinette model for this fall and set it up a bit differnt, but based on what I have learned this spring. If you understand how a water heater stat was designed to work, and place the metal portion about 1/2 to 3/4 ich above your heat source, the thing will work with out modification. I tried it place directly on the heat source, and it will work, maybe better than the way I have it set up now. but you will have to have the temp set pretty high. It will react very fast to the bulb, like on for 10 off for 30 , on for 10. I could get it to temp, but was worried about bulb life , as they are not desiged to have something touching them. The stat is desigend to be placed on a heat source, so that is not an issue. I though about a digital high tech thermostat, and may put one in a cabinette model, but may be not. sometimes simple is better, and a water heater themostat is designed and has proven history of cycleing tens of thousands of time in it life time. How many water heater thermostats fail before the water heater wears out. Not many. And thier is the whole tinkerer mindset. If you like to reinvent the wheel, a water heater stat is the choice. If your are a teckie. then the digital model is the choice. and for the purists , of course the wafer model it will be.

 

[patandchickens]

Just a comment -- for those who are aiming at stabilizing temps by means of rapid cycling of the lightbulb, it would be smart to replace the bulb each hatch (and possibly using 2 bulbs so you have redundancy), as that will wear them out much faster and you don't want the incubator going dark/cold when you're at work...


Pat

 

[Penturner]

New Egg, You are psychic or what? lol just kidding. But you are right. I actually built a rack to hold the back of the stat toward the bulb and about an inch or less from it. the stat now cycles at about 4 min last I was able to clock it. 2 minutes on 2 minutes off. I am not sure all the drilling out of the front was necessary. Pat exactly right. the stat itself was not built to cycle that fast either. I am pretty certain it will not only wear out bulbs but wear out stats pretty quick as well. I plan to have back up on both since making repairs during an incubation is not the most successful method of hatching eggs. Anyway i have the stat holding a temp of 99.6 degrees. I will have to wait a couple of hours and check to see if the digital thermometer recorded any wavering over the past 3 or 4 hours. but at the very least I am certain I have the heat control I need with a Water Heater stat. I am thinking of actually running a 23 day test and see if it is able to manage to hold together for an entire incubation. The incubator is still air right now so other temp measurements are all over the place. But if I was handed the egg from the golden goose right now I could manage to get something done with it. I love just the tinkering and getting different set ups that are sure fire designs. I will put some photos on my Incubator page as soon as I can get them.

 

[Barred Rocker]

Ok here's my set up. I have the water heater stat about 2 inches from the diffusing vent (a plastic bucket bottom with holes drilled in it). The fan and three 60 watt bulbs blowing across a water tray with sponges in a separate compartment. I tried the stat in that compartment at first but it didn't keep the temperature even in the egg chamber so I moved it so it receive the heated air as it came in. Works well, my temp remains steady with about a degree variation and that's usually between night time and mid afternoon. No points for beauty but it gets an "A" for functionality.

 

[Penturner]

Thanks Barred Rock. I have now had my set up crash twice. It runs just fine for about 24 hours or so then suddenly drops 13 degrees. I am satisfied that the stat near the lamp is not reliable. At best it is something that works if you are lucky, and I am not looking for a lucky design. I am looking for a design that anyone can build with specific components and get consistent results. It seems to me that the setting of the Water Heater stat changes when it is close to the heat of the lamp. I started building a heat box last night in order to do just what you show here. I was debating what I thought the results of stat placement woudl be and if it is better to put it in the egg chamber or keep it in the heat box. Thank you for the very timely information.
One question. Is your fan controlled by the stat as well or dies it run all the time? thanks. for the moment I will simply set this box in the incubator but if it works well i will eventually mount it to the back and use PVC pipes to run the air into the egg chamber.