Element Sizes vs. Oven Size

[itsallgood]

Wow, what a lot of information on this site. I've been browsing as a 'guest' for quite some time and I think I'm finally ready to build a decent oven. Being my fist post I'd like to thank everyone for the information that they have already given me!

Here is what I plan to build, with questions to follow:

4' Wide x 8' Long x 4' Tall (Top Loader)
20ga CRS Inside & Out
2"x4" Metal Studs
4" Mineral Wool (To Fill Walls Completly)
1 - 1550rpm 8" Circulating Fan (To Circulate the air inside)
2 - Light Bulbs (One on each end)
1 - Digital Thermometer
? Elements
? Thermostat

I currently have an oven(s) that I use to do smaller parts, basically two conventional ovens put together side by side. There are two bake elements and 2 broil elements. I never use the broil elements b/c I never needed them.

Is there any way to tell what size elements they are?
Will these 4 elements be enough for this size of oven (128sq/ft)?
Will the thermostat I am using now (out of the orginal oven), be adequate to run all 4 elements?

I'm very new to the elements, watts, btu's, of ovens. A friend of mine is a very good electrical guy and wired my current oven.

[KZjim]

put an Ohm meter on the elements and mesure the resistance and do the math from there..
I have talked to Timco, they make elements and they use the watts-per-cubic-inch formula.. not BTU's like i did. give them a call, the local rep here in ATL was really helpfull. I bought a timco thermostat (150 to 550deg) and it works great with a 200amp contactor from Granger, i run 240.
My oven ramps up to 400 from cold in about 10 minutes, i have 3 1500 watt elements.

[itsallgood]

Whats do you suggest I should use in a 4'x8'x4' oven for heating?
I'm running a 60amp breaker. I would like to keep it down to two elements but would run more if needed.

I can find anywhere to get that fan from grainger that I was planning on using.
Anyone know where I can get a motor and blade at that will be sufficent for this oven size?

Thanks in advance!

[pickleboy]

Originally Posted by itsallgood

Whats do you suggest I should use in a 4'x8'x4' oven for heating?
I'm running a 60amp breaker. I would like to keep it down to two elements but would run more if needed.

Thanks in advance!

that size oven with good insulation and few small leaks will need in the 9500watts range. that equates to around 45 amps. you should be ok with the 60 amp contactor.

[itsallgood]

I puchased 3 each of the 3100 watt elements, hopefully this will get me close enough and not take forever.


I had a couple of questions above that no one has replied to and figured I'd do a little refresh on them:

The thermostat that I'm currently using in my fat oven (not pregnant, lol), will it work with 3 3100W elements?
Anyone know where I can get the fan/blade that will work for this temp, and be sufficent for my application?

[pickleboy]

Originally Posted by itsallgood

The thermostat that I'm currently using in my fat oven (not pregnant, lol), will it work with 3 3100W elements?
Anyone know where I can get the fan/blade that will work for this temp, and be sufficent for my application?

the thermostat should work since in most cases the thermo is wired to control the contactor so the draw of the elements do not go through the thermo. this means it is low amp draw and basically a switch for the elements. as for the fan blade and motor. most have used setups from grainger or try mc master carr

[itsallgood]

Thanks for the info on the thermostat!

I can't find anywhere to order from Grainger as they only sell to an already established business.

[KZjim]

http://www.tempco.com/controls/thermo_bulb&cap.htm start there .. i have their unit installed and it works great.. just pick the temp range... my unit range is from 100 to 550 and is DPST it controls the contactor and the light in the oven as well as an "on" pilot light.
As for the fan blade.. just go to your nearest appliance parts store.. they have all types of fan blades. thats where i got mine.