DIY Electrical Evaporator Design - Page 1

[Cedar Eater]

I couldn't let well enough alone, so I made a bare-bones electrified evaporator with an immersed 4000 Watt spa heating element in a steam table pan with a simple 2-pole 20 Amp light switch. I'm calling this new frankenboiler an eEvaporator. My general philosophy when making prototypes is, "Better is the enemy of good enough." This frankenboiler won't win any beauty contests, but it will safely boil sap.

http://i.imgur.com/K4Uqxuc.jpg

I have sufficient outdoor 240 Volt power available to run this and the In-Sink-Evaporator. The combination gives me about 3.5 sqft of boiling surface area, with 1.5 of that from the eEvaporator. Next Spring, I'll be able to do some side by side comparisons, but I mainly did this to make a simple-enough DIY project so that others who are interested can build a cheaper-than-propane method of making syrup. My goal was to make a 240 Volt appliance that is safe enough for outdoor operation in the maple sugar season, assuming that you use reasonable precautions, like wearing rubber-soled footwear and unplugging the pan when boiling is finished.

The Outdoor Evaporation Area

It may seem tempting to dismiss this project due to a lack of 240 Volt power outdoors at your home. I am qualified to do my own work on this front, but you may have to find a relative or friend with appropriate experience who will work for syrup. The amount of power that you have available will determine how many of these electrified steam table pans that you can operate, so before I get into the building instructions for the pan, I'll throw out some ideas you can use to get power out to a sap boiling area.

Of course, anything you can do to help make the sap cooking area reasonably dry and sheltered from rain and snow will help. I fastened a tarp under the soffit of my home's roof and sloped it out to the handrail of my deck in order to give myself some protection from the elements. A covered patio, carport, or even a screen tent may be an option. Unlike with propane, you don't have to worry about wind. Wind is your friend because it moves vapor away from the liquid surface.

240 Volt Power Options You May Not Be Aware Of

Most homes come with some dedicated 240V circuits that might be useful so that you will not have to install a new run back to your breaker panel. If you have a standard RV hookup, an electric smoker, or a pool, spa, or hot tub outdoors, you may have some possible options. I have a spa on my deck. It has a 50 Amp feed from the main breaker panel to a fused disconnect box that by law has to be located within sight of the connection point at the spa, which is under the deck. I fed the power from the fused disconnect box into a new outdoor load center (breaker panel) and installed one 50 Amp two-pole breaker for the spa and one for a receptacle for a range that has been re-purposed as a smoker. I can use the smoker receptacle for my eEvaporator and In-Sink-Evaporator. I can minimize the power requirement of the spa during the sap boiling season.

Garages, barns, or shops can be another source of power. If you have a welder outlet or any other 240 Volt plug-connected equipment outlet in your outbuilding, you can use those with appropriate extension cords. If you have a subpanel in an outbuilding, a new circuit from there might be cheaper than a new circuit from your house.

If you have 240 Volt power routed through an unfinished basement or crawlspace to a range, water heater, air conditioner, or electric dryer, this gives you an opportunity to tap into those circuits and save some money on installation. The installation may not be "up to code", which normally requires dedicated circuits for each 240 Volt appliance, but the building code is there to protect people from contractors who would cut corners. A homeowner who is willing to live with a little inconvenience, like not being able to run their clothes dryer while boiling sap, is simply practicing load management. Adding another receptacle to that circuit to utilize it for another purpose is not unsafe.

A small hole can be drilled through the side of your home to feed a cut extension cord through, and then a new end can be installed on the cord and plugged into your dryer, air-conditioner, or range receptacle. For each eEvaporator, you'll need 16.667 Amps of 240 Volt power. I recommend a NEMA L6-20 power cord for outdoors. They have 20 Amp twist-locking connectors rated for 250 Volts.

Of course, if your circuit breaker box is handy in a location where adding new circuits doesn't require much renovation, new circuits from it with all the appropriate permits and inspections are certainly advised, but not necessarily safer than the alternatives. The savings over propane for boiling sap are significant, but doing things "the right way" can be very expensive.

How To Build An eEvaporator

I'm going to assume that anyone who can use a hammer, drill, pliers, wrenches, screwdriver, wire cutters, knife, and circular saw is qualified to build this.

Materials list:

1 - Deep (6" minimum) full-size steam table pan (http://www.amazon.com/Winco-SPF6-6-Inch-Pan-Full/dp/B001VZ6XP4/ref=lh_ni_t?ie=UTF8&psc=1&smid=ATVPDKIKX0DER)
1 - BX5000C 4KW Universal Heating Element (http://www.spadepot.com/shop/Universal-Flo-Thru-Spa-Heater-Element-10-P803C707.aspx)
1 - 20 Amp Double Pole switch (http://www.homedepot.com/p/Leviton-20-Amp-Double-Pole-Commercial-Switch-Ivory-R51-0CSB2-2IS/202027031)
1 - Simpson Strong Tie 3" X 5" tie plate (http://www.amazon.com/Simpson-Strong-TP35-8-inch-5-inch/dp/B000KKVJQO/ref=pd_sim_sbs_60_4?ie=UTF8&refRID=1SB8TXZ6FPFWAZPY0M5E)
1 - 6' NEMA L6-20 extension cord (http://www.amazon.com/gp/product/B0047E4MP4/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A2TKRNSTU1D8TF) or 6' of 3 Wire 12 AWG flexible cord and a NEMA L6-20P plug end, or, if you think you will want to switch the heater element down to 120 to use the pan as a warmer, 1 - NEMA L14-20 extension cord (http://www.amazon.com/NEMA-L14-20-Extension-Power-Cord/dp/B004XVZIJ0/ref=pd_sim_sbs_60_1?ie=UTF8&refRID=09K6SZ1TS4G9F595GZBP) or a 4-wire 12AWG cord and L14-20P plug end
1 - 2m high temperature lead wire (http://www.amazon.com/Spare-14AWG-Temperature-Resistant-Silicone/dp/B00EZH2M3M/ref=pd_bxgy_60_text_y)
1 - light switch box of your choice (raintight if you think you need it)
1 - 1 X 8 X 10' or 2 X 8 X 10' board
2" or 2-1/2" wood screws (depending on which board you use)
Crimp-on wire terminals


It takes over six quarts of liquid to immerse a spa heater element installed at the bottom of a full-size pan, and you don't want to run the element dry. If lifting the pan to dump that much liquid seems like it would be too heavy, you can scoop out some of the concentrated sap before dumping, or install a drain valve for the pan. I'm trying to show a minimal cost project, so I'm not including a drain valve. You might be tempted to use a shallower pan to minimize cost, but a shallow pan will have more problems with overflow and splashing than a deep pan.

Hold the element lengthwise in the center of the bottom of the pan and note where the terminals for the element will contact the pan. I think it's better to run the element lengthwise to minimize overflow and splashing. This is how the pan looks when water is boiling in it.

http://i.imgur.com/PbCgfB9.jpg

Note that the terminals do not line up perfectly along the imaginary centerline of the pan and are not perfectly centered in the element. In order to center the element, you will have to offset the holes for the terminals. A rough approximation is sufficient. I used a Sharpie to mark where the first hole would be best, and after placing a sacrificial block of wood under the pan, I used a hammer and a 20D nail to punch a small hole in the bottom of the pan. I measured 1-1/4" from that hole, offsetting the tape slightly, and made a second hole.

http://i.imgur.com/nbPRPZn.jpg

I used a set of titanium drill bits to expand those holes out in small steps to the 1/2" diameter required for the spa element. Taking small steps (1/32") gives you the opportunity to adjust the centers of the holes to ensure that they are precisely 1-1/4" apart when the final 1/2" hole diameter is reached. Aiming the drill slightly toward the other hole when drilling will move the centers closer together and aiming the drill slightly away will move them apart. When finished drilling, it may be necessary to debur the edges of the holes with a round file to get the terminals to fit through them. This is how it looks when they are ready for installation of the element.

http://i.imgur.com/p2JVaCN.jpg

Continued on Page 2

[Cedar Eater]

You're not done drilling metal yet, but now the metal will be softer. This step is optional, but I highly recommend it. In my opinion, it is too risky to rest this pan on its terminals, and whenever it's out of the box, that could be a problem. They are not designed to be load bearing. So to protect the terminals from bashing in the future, the Simpson Strong-Tie plate will become a guard for them. Once this guard is installed, setting the pan down on its bottom will risk scratching the surface you set it on, but setting it on its terminals would risk the same and would also risk breaking them. So drill holes in the plate so that it will fit over the terminals as shown.

http://i.imgur.com/CeXLMR5.jpg

Bend the plate as shown below. I used pliers to start bending the plate at the second row of holes from the top and bottom and then hammered the plate around the edge of a 2X4.

http://i.imgur.com/4lpVwRS.jpg

The next steps are to support the pan in a frame and provide power to it. You could simply set the pan on wooden sleepers on the ground, but it will lose heat if it's not enclosed and insulated, and you would have to find a way to safely wire it. A standard steam table pan fits into a hole that's 12" by 20". That gives the pan a little room to grow when it gets hot. The easiest durable-enough frame for me to make was a box made from 1 X 8 boards and wood screws. Wood serves well enough to insulate, but a box could be oversized and then lined with rigid board insulation and even aluminum foil to make it better. There would be no need to make it deeper, because there is room under the pan for an inch of insulation, except near the terminals.

I notched opposing corners in the box to make it easier to lift the pan out to pour the concentrated sap into a pot for finishing. I'm right handed, so I notched what would be the nearer left and farther right corners (when considered from a long side), because this seemed the most comfortable for pouring away from my feet out the farther left corner.

http://i.imgur.com/kpRDHWQ.jpg

The early design included a fuse block being used as means to plug the pan into the base. The fuse block did not work out because the terminals of the heating element get too hot, so the fuse block has been removed from the design. Simply hard wire the leads with the high temperature wire and crimp-on ring terminals.

Continued on Page 3

[Cedar Eater]

Before I go further, I want to emphasize that my plan is to always unplug the power from the source before lifting and pouring the concentrated sap out of the pan. If built according to this design, there should be no danger of electrical shock, but boilover and spillage are variables where it doesn't hurt to make sure the equipment is unplugged whenever boiling is not intended. While boiling, I wouldn't recommend routinely touching the heating element with a strainer while scooping foam, but it shouldn't be dangerous.

The initial design of this prototype contained an infinite switch for controlling power that just isn't necessary or even useful when the wattage is kept within the range that's reasonable for a steam table pan. So I've simplified the design to use a simple 2-pole on-off switch matched to the wattage range.

The next steps are to mount the switch and wire everything. I used a double wide metal box, in case I ever want to mount a second switch for dropping the voltage to 120, but really because I just happened to have one available. I connected a 4' ground wire from the guard of the heater element terminals to the ground connection inside the switch box. This keeps the box grounded in case you forget to turn the power off when you lift the pan, but it also limits how far you can move the pan from the box. I used high temp wire to connect the fuse block to the load side of the switch and connected the cord to the line side of the switch.

http://i.imgur.com/Nqbk63m.jpg

This is about as basic as I can imagine for a safe outdoor 240V appliance. I'll let you know if I encounter any problems with it.

[maple flats]

I looked at your plans just out of curiosity, since I have a 3x8 wood fired rig, but I have a question. What is the temp. rating of the wire under the unit? Since you will be boiling up to 219 or 220, you will want that wire to be rated for higher temps. Most extension cords are not.
For those looking to make something like this, be sure the wire(s) used under the unit, where the heat will easily reach 220, are rated for those temperatures. They will usually be stated on the cord jacket in Celsius. You will want wire rated at over 105 or the insulation on the wire will break down and eventually fail, possibly causing a short (or worse).

[Cedar Eater]

I looked at your plans just out of curiosity, since I have a 3x8 wood fired rig, but I have a question. What is the temp. rating of the wire under the unit? Since you will be boiling up to 219 or 220, you will want that wire to be rated for higher temps. Most extension cords are not.
For those looking to make something like this, be sure the wire(s) used under the unit, where the heat will easily reach 220, are rated for those temperatures. They will usually be stated on the cord jacket in Celsius. You will want wire rated at over 105 or the insulation on the wire will break down and eventually fail, possibly causing a short (or worse).

Edit: I've revised the design since my original response was written. Thank you maple flats for inspiring me to think of better internal wiring.

[Cedar Eater]

Edit: I've revised the design since this post was written. I'm just leaving it in for reference.

Update on the cord rating:

The cord that I specified, 12/3 Type SJOOW, is rated at 25 Amps at 90degC instead of the 20 Amps I was assuming. A better cord would be 12/3 Type SJTOOW, but operated at 15 Amps, I'm pretty confident that the Type SJOOW will perform well, except possibly right at the heater element terminals. Inspect it there when dumping the concentrated sap and replace it with higher temp wire if it shows signs of melting.

Further update on the cord rating:

A conflicting source claims the 25 Amp rating of Type SJOOW cord is for 30 degC, implying that the 90 degC rating is an absolute rating independent of the current. Unless I can find and link to a source of SJTOOW cord, I will switch to high temp lead wire and change previous posts to reflect that.

Further update to the cord specification:

I changed the cord spec in the materials list to a Type SJEOOW, which is rated for 105 degC. Since it will be operated at 15 Amps, and since the pan is for reducing sap to nearup and not for producing finished syrup I think the box temp will not exceed the cable rating. If it does, I would expect degradation to show up first at the terminals of the heating element. If I saw that, I would replace it with high temp lead wire.

[Waynehere]

Another consideration along with the quality of the cord is the breaker. If that element is only pulling 15 amps, be sure to only have it hooked up to a 15 or 20 amp breaker. Reason is that if for some reason that element did run away on you or went dry, that cord will burn up with too high of a rated breaker before it will ever pop. Always match your protection to your appliance needs as well as the cord. Breakers are usually pretty easy to change out, even if temporarily.

[Cedar Eater]

Edit: I've revised the justification used below because the infinite switch initially used with this design is removed from the system.


Another consideration along with the quality of the cord is the breaker. If that element is only pulling 15 amps, be sure to only have it hooked up to a 15 or 20 amp breaker. Reason is that if for some reason that element did run away on you or went dry, that cord will burn up with too high of a rated breaker before it will ever pop. Always match your protection to your appliance needs as well as the cord. Breakers are usually pretty easy to change out, even if temporarily.

That's not really required and isn't even considered to be good design practice. It's a common misconception that it's the function of circuit breakers to protect against the failure of plug connected loads. The circuit breaker's function is to protect the wire and cable routed to the outlet through the home from overload and downstream short circuits, not from downstream overloads that put cords at risk. Houses are full of 20 Amp breakers feeding power to plug connected loads that have cords rated for 10 Amps (or less) through receptacles rated for 15 Amps. That covers many of the lamps in your home.

With plug-connected loads, the nature of the load is its protection against overload. Heating elements are very reliable and are already very low resistance. That's why they don't even put a "red button" device on coffee makers and crock pots. When they fail, they almost always fail open, and when they don't, they quickly short circuit and trip the first upstream breaker, which is the function of the home's circuit breaker. No additional circuit breaker or fuse is required, but it wouldn't be hard to add a fuse inside the box on one or both of the leads to the heating element if you want to play it safe. A fair criticism of this design is that it does not protect against high temperature resulting from dry fire of the element. If anybody has any ideas about that, please contribute them.

[Mel]

Might it be worth considering adding a layer of Roxul for the pan to set into? Maybe the thickness of the Simpson thingy? Would serve to keep heat in the pan, and away from the rest of the components.

[Cedar Eater]

Edit: I have since revised the design so that it does not have a cord between the switch and the pan. I like the idea of having insulation of some sort under the pan. I'm leaving the original post intact for reference.


Might it be worth considering adding a layer of Roxul for the pan to set into? Maybe the thickness of the Simpson thingy? Would serve to keep heat in the pan, and away from the rest of the components.

That would be great if it didn't interfere with lifting the cord out to dump the pan. I guess it would have to come out with the pan so the cord could coil beneath it. I tried to find a spring clamp mechanism to mount to the bottom of the box that would grip the heater element terminals when the pan was set into them, similar to the way some stove burners plug into a receptacle under the stove top. That would remove the necessity for a pan cord. I just didn't find anything that was designed to grip the spa element terminals. If anybody has any ideas on that, I would be happy to add that to the design.

[Cedar Eater]

Edit: The fuse holder mentioned below did not work as a receiver for the heating element terminals. I've left this post in for reference.

I might have just short circuited (pardon the pun) the pan cord issue. I'm looking at a midget fuse block (http://www.amazon.com/Littlelfuse-L60030M-1PQ-Midget-Cartridge-Shipping/dp/B00KBIWRVG/ref=lh_ni_t?ie=UTF8&psc=1&smid=A1UOBWSFLOXPFW) that, if attached at the right height in the bottom of the box, will clip onto the locknuts on the terminals of the heater element when the pan is in the right position. My intent would be to have the power off when setting or disconnecting the pan. I would need to do something similar for grounding the pan, but if this works, I would just use high temp wire between the fuse block and switch. It would make pan alignment more critical, but some spacers mounted on the sides should help with that.

[Cedar Eater]

Edit: I've revised the design since this post was written. The 5500W element was just too much for this pan. I've left this post intact for reference.

I just finished testing the eEvaporator with reworked internal wiring. I removed the pan cord and I have a green ground wire and two high temperature wires running between the pan and the switch now. I also rerouted my 90 degC rated cord through the wood directly into the tunnel for the infinite switch. I intend to leave the previous hole open as a source of cooling air for the switch tunnel.

For the smoke test, I put three gallons of 60 degF water into the pan. The air temp was around 75 degF. I turned the switch to Max and had a roiling boil in 15 minutes. I'm wondering if the boil isn't too vigorous. The water actually got into a rhythm, rolling from side to side but not sloshing out. I let it boil for an additional 15 minutes, turned it off, and let it cool. I measured the remaining water and found it to be only 2-1/4 gallons. That impressed me.

One thing that concerned me is that the infinite switch did not shut off even once during the half hour. I read almost 20 Amps while it was running. That's right at the rating of the wiring and almost 5 Amps higher than the switch was supposed to deliver. I inspected all the wiring and the wooden box and found no indication of overheating. I'll be monitoring to see if 20 Amp wiring should be upgraded to 30. I was a little concerned that the element terminal nuts wouldn't conduct power in to the terminal leads well, but it sure doesn't seem that there was any problem there.

I will edit the initial posts to reflect this design change when I get a round tuit.

[bkeith]

When you turn an infinity switch to Max, it never turns off. Only the settings below Max will cycle on and off. I don't think you'll get a satisfactory boil when it is cycling several seconds on then several seconds off.

Better to use a triac-based power controller, like a massive light dimmer. In another hobby, where they boil things and want to control the amount of power fed to the element, a 120V 15A router speed controller works very well. Sourcing a 240V equivalent shouldn't be hard.

[Cedar Eater]

When you turn an infinity switch to Max, it never turns off. Only the settings below Max will cycle on and off. I don't think you'll get a satisfactory boil when it is cycling several seconds on then several seconds off.

Better to use a triac-based power controller, like a massive light dimmer. In another hobby, where they boil things and want to control the amount of power fed to the element, a 120V 15A router speed controller works very well. Sourcing a 240V equivalent shouldn't be hard.

Thanks. I will look into that. This switch is concerning me as the weak point of the system. I believe that, even though it is handling the current, it might fail prematurely due to the contacts operating at or possibly above their max. If I can't find a suitable controller, I'll switch to a 120V/240V selector switch and increase the wire to 10AWG. The alternative is to decrease the power to <=3600W, which might still boil this pan, but probably nothing larger.

Edit: I couldn't find a way to add a Triac based controller to the system cheaply. If anybody has one they can recommend, please let me know. Otherwise, I've revised the design to a specific wattage of heating element, 4000W that draws less than 20 Amps and supplies a less boisterous boil.

[Cedar Eater]

I decided to test this box with a 4000W heating element and I'm liking the results a lot more. The boil took only 5 minutes longer to achieve and it is not as vigorous, but there was no visible splashing of tiny drops outside the pan edges as there was with the 5500W element, and it appears to be more than good enough. If that turns out not to be the case in cold weather (which I believe is highly doubtful), it will be possible to upgrade to a 4500W heater element without compromising the rest of the new design. Because of the extra five minutes required to achieve the boil, I let the three gallon test go for 35 minutes instead of 30. The amount of water remaining after the cooldown was only slightly more, still in the neighborhood of 2-1/4 gallons.

With the decreased vigor of the boil, the need for controlling the element went away. This pan will be used for evaporating sap, not finishing the syrup and because of the amount that must remain in the pan to keep the element covered, there is no reason to use it as a warmer. A simple on-off switch is cheaper and I believe safer and more reliable than the infinite switch, so I'm going with that and removing the infinite switch from previous posts. If you really want to use the pan as a 2-4 gallon warmer, the addition of another switch, a 3-way 20 Amp switch (http://www.homedepot.com/p/Leviton-20-Amp-3-Way-Commercial-Toggle-Switch-White-R62-0CSB3-2WS/202034997) would allow you to drop the voltage across the element to 120V and reduce the power drawn to 1000W, by switching the neutral wire to the element instead of the L2 wire. Note: To do this you will need to upgrade the plug and cord to a 4-wire L14-20 (http://www.amazon.com/NEMA-L14-20-Extension-Power-Cord/dp/B004XVZIJ0/ref=pd_sim_sbs_60_1?ie=UTF8&refRID=09K6SZ1TS4G9F595GZBP) and have a source that is 4-wire 120/240 instead of 3 wire 240. There's a way around that, but it isn't pretty.

During the test, the current read only slightly over 15 Amps, which is near to the 16.667 calculated for 4000W at 240V. So I will be installing a 2-pole 20A switch in a surface mounted box. This will remove the need for a cord rated at 105C, so the cheaper 90C cord that I originally specified will suffice. I will shorten the specification to a 6' cord because the pan cord has been replaced with separate insulated wires.

[bkeith]

This should do it. http://www.ebay.com/itm/LED-Display-AC-220V-10000W-SCR-Voltage-Regulator-Speed-Control-Dimmer-Thermostat-/221464802245?pt=LH_DefaultDomain_0&hash=item339054b3c5

or this http://www.ebay.com/itm/New-4000W-AC-220V-SCR-Voltage-Regulator-Speed-Controller-Dimmer-Thermostat-/261192160445?pt=LH_DefaultDomain_0&hash=item3cd04414bd

or this http://www.ebay.com/itm/New-AC-220V-5000W-SCR-Voltage-Regulator-Speed-Control-Dimmer-Thermostat-/221753682054?pt=LH_DefaultDomain_0&hash=item33a18ca886

or this http://www.ebay.com/itm/10000W-220V-SCR-Super-Power-Regulator-Motor-Speed-controller-Dimmer-Thermostat-/261841258456?pt=LH_DefaultDomain_0&hash=item3cf6f487d8

To name a few. There were many more, in different configurations.

All seem economical and easy to integrate. I'd probably go with one of the 10kW units so as not to be pushing it to the max.

[Cedar Eater]

This should do it. http://www.ebay.com/itm/LED-Display-AC-220V-10000W-SCR-Voltage-Regulator-Speed-Control-Dimmer-Thermostat-/221464802245?pt=LH_DefaultDomain_0&hash=item339054b3c5

or this http://www.ebay.com/itm/New-4000W-AC-220V-SCR-Voltage-Regulator-Speed-Controller-Dimmer-Thermostat-/261192160445?pt=LH_DefaultDomain_0&hash=item3cd04414bd

or this http://www.ebay.com/itm/New-AC-220V-5000W-SCR-Voltage-Regulator-Speed-Control-Dimmer-Thermostat-/221753682054?pt=LH_DefaultDomain_0&hash=item33a18ca886

or this http://www.ebay.com/itm/10000W-220V-SCR-Super-Power-Regulator-Motor-Speed-controller-Dimmer-Thermostat-/261841258456?pt=LH_DefaultDomain_0&hash=item3cf6f487d8

To name a few. There were many more, in different configurations.

All seem economical and easy to integrate. I'd probably go with one of the 10kW units so as not to be pushing it to the max.

Thanks, I like those. I didn't find anything near that cheap when I searched. I think I'll buy one for my In-Sink-Evaporator, where I think it will be much easier to integrate. The In-Sink-Evaporator is 33% larger in surface area, twice the liquid volume, and has a bottom drain, making it more likely that it would need a variable boil. I'm a little concerned about using these controllers outdoors for this design. I plan for my area to be sheltered from falling rain and snow, and I'm not planning to have raintight switches, but fog, wind-driven mist, and condensate from the boil are a concern. These don't seem to be suitable for mounting inside the box due to the heat, or on the side of the box due to the lack of protection of the components and the need to keep them well ventilated. I'm trying to keep this design simple enough to easily replace the propane burner option, so building a weather-tight instrument panel for the controller is no small matter. I wish I could cheaply simulate the conditions of late Winter - early Spring on my deck to verify that 4000 - 4500W will be enough for the steam table pan, but I'm confident enough that I think I will just stick with the on-off controls for it.

[Cedar Eater]

I've finished editing the first three pages after the failure of the fuse block. It is now in syrup production and I am watching all the connections for signs of overheating and insulation failure.

[TrapperX]

You have inspired me! Are we getting close to a real world test with sap :cool:

I am looking at this Titanium one and have a 19x11x6 pan.
Plans would be to build an insulated box for it.
Have you thought of any thing else you would improve on?
Posting this real quick on my way out to tap a few more trees before dark.


http://www.amazon.com/gp/product/B00TQ0MFZI?keywords=Titanium%20Heater%20Element%20 10&qid=1455831947&ref_=sr_1_2&sr=8-2

http://www.amazon.com/gp/product/B00OZ4UWGY?psc=1&redirect=true&ref_=ox_sc_act_title_2&smid=A2OCOGC9B25845

http://www.amazon.com/SMAKN%C2%AE-0-220V-Modulator-Electric-Controller/dp/B00UKK50UK/ref=sr_1_fkmr0_1?srs=7885600011&ie=UTF8&qid=1455834637&sr=8-1-fkmr0&keywords=AC+220V+20A+Pulse+Width+Modulator+10000w

[Cedar Eater]

You have inspired me! Are we getting close to a real world test with sap :cool:

I am looking at this Titanium one and have a 19x11x6 pan.
Plans would be to build an insulated box for it.
Have you thought of any thing else you would improve on?
Post this real quick on my way out to tap a few more trees before dark.


http://www.amazon.com/gp/product/B00TQ0MFZI?keywords=Titanium%20Heater%20Element%20 10&qid=1455831947&ref_=sr_1_2&sr=8-2

http://www.amazon.com/gp/product/B00OZ4UWGY?psc=1&redirect=true&ref_=ox_sc_act_title_2&smid=A2OCOGC9B25845

http://www.amazon.com/SMAKN%C2%AE-0-220V-Modulator-Electric-Controller/dp/B00UKK50UK/ref=sr_1_fkmr0_1?srs=7885600011&ie=UTF8&qid=1455834637&sr=8-1-fkmr0&keywords=AC+220V+20A+Pulse+Width+Modulator+10000w

I'm real close to testing it. All I need is sap. I haven't made any other changes. I left it sit outdoors all year to see how it would weather. It passed that test.

[maple flats]

You can make sap by taking 1 pt of maple syrup and add about 40 pints of good potable soft water, (not softened with salt). then mix it well. However when you get back to syrup it will be much darker than what you started with.

[Cedar Eater]

I finished the first sap boil tonight. I am extremely pleased with how it went. I reported the results here http://mapletrader.com/community/showthread.php?27727-First-boil-of-the-season-on-my-new-homemade-electric-evaporator, but a brief recap is that the 4000W element worked fine with an outdoor temp that fell below freezing during the boil. I calculated the evap rate at 1.25 gph from a cold start. I added whole gallons of cold sap during the boil and the boil recovered quickly each time. I walked away and let the box do its thing for half hour periods throughout the boil. I wish I had thought to measure the box internal temp during the boil. I'll try to remember that next time.

[Cedar Eater]

It's late and I might not be thinking straight, but my simplified view of the energy cost per gallon of syrup produced, assuming 40 gallons sap per gallon of syrup is

39 gallons sap boiled/1.25gph = 31.2 hours boiling time x 4kW = 124.8kWh x $.137473/kWh = $17.16/gallon

I have no idea how that compares to propane at current prices. I know I can beat it with wood, but I can't walk away from a wood fire for a half hour at a time.

[Cedar Eater]

After 16 hours of runtime, the fuse holder failed by melting/burning. I measured the temperature inside the box while it was in operation and it never went above 70F and only one side of the holder failed. It seems clear that one terminal of the heating element got much hotter than the other. I'm not sure what caused this but I suspect it was just that the nut on the heating element terminal was not tight. I really like the idea of plugging the pan into the base, so I'm going to work at finding a way to keep doing that, but for now I've just hardwired the leads to the heating element terminals.

13741

[Cedar Eater]

I've finished two small batches this year with a new modification that allows me to plug the pan into the base so the leads for the heating element terminals don't have to be directly connected. I salvaged the spring clips from the melted fuse holder and mounted them at the top of two small towers made from two different sizes of flat washers. The washers radiate away the heat that comes down from the heating element terminals. So far, the wood beneath the towers where the mounting screws attach has shown no sign of excessive heating and because it is dry, it is good electrical insulation.

15564

[Colin1234]

Dear community,

I'm a folk from a suburb of Montréal (Laval) where I tapped a dozen of maple trees of neihbours around, in exchange of sirup. I have 20 taps.
Last year I evaporated 5 taps in my kitchen, did a hole mess. So this year I was looking around on internet to find ways to evaporate the water. First taught of a rocket stove, but with neihbours juste a fence away, it was not the best to play with fire.
Then I ended up here in this thread. Wow. It inspired my plan from A to Z. Thank you!

So here is in few words my set-up:
- could not plug myself in a 240V, so I bought 6 120 V element of 1440 Watts each, for a total potential power of 8640 watts. My breakers circuit are 15 amps and each element with pull 12.5 amp so I should be fine plugging my elements in 6 different circuits of the house.
- the difficult part was to fit the element in a cauldron, because the elements have a diameter of 1''. Did a hole with a 1''1/4 hole saw. Finding a 1''nut was hard, because it's a NPS thread (didn't know the difference between NPT thread and NPS thread, the latter being not common). With silicone washer, the elements are watertight. The cauldron has a volume of 100 litres.

Now my trees are tapped, waiting for the sap and will probably first test this version of electrical evaporator sunday. As people said, Quebec electricity is 6 cents/kw-hr!

Here are some pictures. Comments and insights are more than welcome :)


19681
19682 19683

[fisheatingbagel]

Looks like it has great potential to really boil! Let us know how it goes...

[Cedar Eater]

Then I ended up here in this thread. Wow. It inspired my plan from A to Z. Thank you!

You're welcome! Glad to see that you're trying something different. You might want to run with your level down close to the top of the elements to maximize your boil rate. Also set your pan in a non-flammable, non-conductive insulator to cut out heat loss through the bottom. I would love to see and hear how it works for you.

[Colin1234]

Hi everyone!

I am very excited to tell you that my first boiling is happening right now.
With just 4- 1440 watts elements out of 6, it took 40 minutes for the sap to boil around 45 litres. Didn't use the other two elements, had trouble finding two free breakers. I like to have two spare elements, because if one of my wire extension gets too hot, then I can switch to another one (I have 6 extension cord, most of them 16 AWG, which is limit from what I understood)

So far so good, the breakers are holding, such a great feeling to look at this steam coming out of the evaporator.

Here are some pictures. The set up is not the best one, I put the evaporator on two fire bricks, I know I am loosing a lot of heat since the thing is not insulated at all. ''Better is the enemy of good enough'', Cedar Eater said ;)

But it's not done yet, I am still far from good taste syrup!

1984819849

[Colin1234]

Update: I am at almost 2 gallons of syrup so far.
The evaporator is doing great, I started boilling 80 litres of water this afternoon, my biggest volume of water at a time so far, took a bit less then 1 hour to reach boil temp.

While boiling, I had a question... 5 elements at a time manage to boil a lot. Does it evaporate faster when the boil is ''bigger''? Could I remove one or two elements and if it still boilling it will evaporate at a similar rate then 5 elements?

[Fyreaway]

...will it evaporate at a similar rate then 5 elements?

I also use an electric evaporator. The vaporization rate does increase with more power but it's not a linear kind of thing. You won't make syrup five times faster using five elements than one. I use a 4500 watt element and usually run at 70% capacity. The fun thing about your rig is now you get to play with it. You won't ruin anything by changing the power input. Find the sweet spot where the evaporation rate is acceptable compared to running power cords from several different circuits. Added electric user advice...when the heating elements get gunked up dump the sap and fill the kettle with vinegar to cover them. Run it just 'till it's warm and the crusties will pretty much fall off.

[Colin1234]

I also use an electric evaporator. The vaporization rate does increase with more power but it's not a linear kind of thing. You won't make syrup five times faster using five elements than one. I use a 4500 watt element and usually run at 70% capacity. The fun thing about your rig is now you get to play with it. You won't ruin anything by changing the power input. Find the sweet spot where the evaporation rate is acceptable compared to running power cords from several different circuits. Added electric user advice...when the heating elements get gunked up dump the sap and fill the kettle with vinegar to cover them. Run it just 'till it's warm and the crusties will pretty much fall off.

Hey thanks for these tips! Your foresaw another question I had about the element and the sugar, I'll do the vinegar thing. But I did few boil when the elements where a bit darker, I hope it won't damage them if I wait until the end of the season to do the vinegar solution. Because how I am set up, I would need more than 3-4 gallons of vinegar to cover up them all. I could not do that between every boil...

[Fyreaway]

Hey thanks for these tips! Your foresaw another question I had about the element and the sugar, I'll do the vinegar thing. But I did few boil when the elements where a bit darker, I hope it won't damage them if I wait until the end of the season to do the vinegar solution. Because how I am set up, I would need more than 3-4 gallons of vinegar to cover up them all. I could not do that between every boil...

You won't damage the elements with a sugar buildup. They're pretty bomb proof, just don't dry fire them! The downside of not cleaning is a slight off (burnt) taste in the syrup if you wait too long. The vinegar cleaning is pretty simple too. Get the high octane 'cleaning' vinegar and cut it 50/50 with water. I run the vinegar through a coffee filter after cleaning the evaporator and use it many times.

[Colin1234]

All this is great information... Thank you for sharing your know-how, very very appreciated.