External 7-day timer for oven...

[blueman]

I would like to put our oven on a 7 day timer so I can program it to go on and off at times of my choosing.

The specs say that they draw 40A @240V and require a 50A circuit. Even the Intermatic commercial timers seem to tap out at 30A for electronic ones and 40A for manual ones.

Anybody know of a good source of timer that would handle my load?

(interesting aside" my expensive "professional series" Thermador oven doesn't have any timers whereas even the cheap white box appliances are chock full of electronics0

[Tim Fischer]

I'm not sure this is a good idea, nor practical. How many items could you leave in your oven for more than 12/24 hours without going bad, which would necessitate more than a standard timer? Also, it seems like a huge safety hazard. I'm not a big fan of leaving things in the oven unattended to begin with, but to have a separate timer that could potentially be forgotten about, meanwhile someone puts the electric skillet in the oven, oven kicks in 2 days later when nobody's around... Bad news.

-Tim

[lee houston]

uh, this current draw is only when the oven is TURNED ON and the thermostat switches ON. maybe a trickle of current if it has a clock.

How about turning it ON when u want to use it and OFF when through? I assume you're talking about an oven to bake food in?

lol, is perhaps this post is a 'load' and you're pulling our legs?

lee

[dpb]

The timer doesn't have to handle the load--all it has to do is control a relay whose secondary load contacts are size for the actual load.

I would presume this would be because in a "professional" use, one would expect the chef to be there rather than starting the roast whilst in church to be ready for dinner when gets home. (I presume such is the intent of the question, but I also agree w/ the comments that as a device external to the oven it doesn't sound like a real good idea.

If this feature is sufficiently important, would probably be a better solution to find a range/oven that incorporates the timer, but it certainly _could_ be done as noted above.

The real problem here is that the only way to make it work is to leave the oven "on" all the time whereas the internal timers actually turn the oven itself off. I suppose if one were to get only a "single-shot" timer it would be essentially the same, but a continuous 7-day/24-hr timer w/ the oven always on is, I concur, a bad idea.

[kevin]

And conveniently, if your oven is is gas (probably not, at 40A) or has an electronic thermostat or timer for the oven, then your existing oven might just have such a relay built in, that is precisely the correct size for operating your oven. All you would need to do is splice pretty much any timer into the existing relay circuit.

[terry]

. Concur sounds like bad idea. However as foot note and not in reply to the question; we have on several electric ovens interposed a relay between the oven thermostat and the oven element. In other words the thermostat now controls a small current to the relay coil and contacts of the relay actually switch the oven heater on/off. Used several types of relays including electric baseboard heating relays and also some surplus but new 230 volt signal relays with suitable contact rating. Being in the catering and school cafeteria business we got tired of replacing directly connected oven thermostats and after this solution we never replaced another! I guess manufacturers don't us a relay because of the additional cost?

[mm]

I agree. My mother was a worry-wort, and it made me a bit reckless, but in this case, I agree with her too.

[Vic Dura]

On Mon, 25 Sep 2006 22:14:10 GMT, blueman wrote Re External 7-day timer for oven...:

You might try a pottery kiln manufacturer or parts supply house. My wife's electric (220V, 40A) kiln has such a programmable control attached to it.

[DT]

I'm not sure what features your oven has, but be aware that if you simply cycle the power off and on, the oven will probably not retain any settings and will turn on at some nominal temperature, or most likely, not at all. If it just uses an old style temperature control with manual settings it should be ok.

I ran into this with window air conditioners, I built an external thermostat to control an older style and it worked like a charm. I left it turned to the lowest temperature and used my thermostat to turn the unit on and off. This give vastly superior temperature/humidity control compared to the factory control. But I tried in on a newer digital unit and it goes into its default mode when the power is interrupted.

-- Dennis