Tiles cause oven temp difference?

How long is the oven on when you are noticing the temperature difference. The tile are going to absorb heat for a long before the temp in the oven is going to balance out.

Tim

Did the oven manufacturer recommended that tiles be put into the oven? If you just personally modified the oven but the equipment does not have an allowance for the corresponding difference of heat due to the absorption of the ceramic surfaces which behaves as a heat sink.. The main issue here is not temperature difference which is academic from the point of the baker. Rather how does the oven perform in the baking process. Are ypu getting excellent bread with that set up even if the dual temperature readinds are not equal. If the answer is affirmative then do not worry about temperature fluctuation. As you already know how to determine tthe desired heat requirements for a certain baked product I have seen ovens in commercial setting that register temperature that is low to be considered suitable for crusty bread baking ; but what is surpising is from the hands of capable ba,ker the breads comes out excelllent. who sense the heat through experience. Meanwhile an apprentice who do the same task usually is unable to get consistent results.. I was wondering if the ceramic tiles is hindering the flow of radiated heat from the hot ooils resulting that the registered temperature fluctuates. Sometimes slight modification of the temperature sensors distance will improve the temperature display to corresponds with the portable thermometer. Usually its a common occurence the in built oven thermometer does not give similar value as the portable thermometer probe you are using. The manufacturer has calibtated the thermoter to register the appropriate um of the convective, radiative and conductive heat in the oven atmosphere. They did not have an allowance for modifications just as you had done. Therefore if you modify the oven by placing tiles then you should correspondingly adjsust the tempereature sensing coil to be elevated or lowered in the same level as your portable taylor thermometer. But if you had baked bread consistently with even that temperaure difference ; then you do not have to worry about it. Let your baking experience be the guide in obtaining consistent result and ignore the temperature difference. Remember baking is not just by following the temperature settings as given by a recipe book but how your commonsense make you adapt the recipe to your system. Roy

Probably depends on the position of the oven's sensor. Can you place your thermometer next to the sensor?

Is the tile against the ovens thermometer/sensor? If so, the oven may be "cutting off" prematurely due to the oven's sensor reaching the desired temperature on the side of the tile next to the heating element and oven's thermometer. If you move the tile away from the temperature sensor in the oven, it should stay "on" until the whole thing is up to temperature, not just on one side of a single tile.

Sid

Thanks for the many responses. To answer a few of the questions:

1. ">Is the tile against the ovens thermometer/sensor?" No, the tiles are on the bottom shelf of the oven, just above the bottom heating element, and the sensor is toward the top of the oven.

1. >Are you getting excellent bread?" Absolutely! (if I may say so myself). But of course we use the oven for all kinds of other things, too, and many of them need relatively accurate cooking temperatures. I suppose I could put the tiles in only when baking bread, but I've read of many people just leaving them in and never heard of this problem before.

2. >"Can you place your thermometer next to the sensor?" The sensor and the thermometer are within an inch or so of each other. So this doesn't appear to be caused by temperature gradients within the oven or a convection problem.

1. >"Did the oven manufacturer recommended that tiles be put into the oven?" Not as far as I know. The oven (Magic Chef, now owned by Maytag) was here when we bought the house, and I haven't found any indication one way or the other. But as I mentioned, I've read of many people doing this - particularly bread bakers - and haven't heard of any problems.

2. >"How long is the oven on when you are noticing the temperature difference?" 45 minutes or more. Once the oven gets up to temp, both readings are stable and the difference doesn't change.

So here I am, still wondering which reading to believe. I am tempted to believe the Taylor, since it's known for its accuracy, and to assume that some weird phenomenon is throwing off the oven sensor. It's a shame, really, because the convenience of having an accurate sensor means we don't have to open the oven, check the thermometer, adjust the temp, check again, etc.

Peter,

The temperature that counts is the stable (adiabatic) temperature of the oven walls and the tiles, attained after adequate preheating (45 minutes sounds like enough).

It may be that the oven sensor is doing a better job of measuring the wall temperature than the Taylor thermometer, which, after all, can only measure air temperature. Can you read the Taylor thermometer through a closed oven door, with the oven light on? (Here I am presuming, with no evidence, that the oven has both a light and a transparent door.) If so, so you find the same discrepancy?

In that case, I would suggest that perhaps your tiles cover too much area relative to the heating element and therefore interfere with convection within the oven. How much clear space is there around the outside of the tiles? How much vertical space is between the heating element and the tiles? If either or both of these is too small, poor convection, especially if it is combined with the opening of the oven door, could account for the difference.

Dick

Peter Cook wrote:

That could be the answer. Our oven is not huge, so to bake relatively large breads I covered most of the bottom rack with the tiles. The space between the bottom of the tiles and the heating element is probably about an inch. I'll try allowing more space and see what happens.

Doesn't the oven sensor measure air temperature, too? It sticks out into the oven about 4 inches and it's located about 2 inches below the top of the oven. How

I can't read the taylor through the door because the door glass is pretty cloudy. But I've opened the door and taken the readings very quickly, both with and without the tiles.

Thanks for your comments, Dick.

Pete

An inch vertical seems tight to me, especially if the margin around the outside is also narrow. Without the assistance of a convection fan, you are relying on the tendency of warmer air to rise through cooler air, and this movement will be slower if it is physically impeded as yours is.

The rest of your question was truncated, but to answer what you meant to ask, the oven probe is reacting both to air temperature and to the heat radiated from the top of the oven, absorbed by the probe's black surface, and thence conveyed to its working fluid (air or whatever). The last time I bought a Taylor oven thermometer (some decades ago), it was a shiny metal case with air holes in the back--not an ideal absorber of radiant heat. I don't know that it is still designed the same way, but if it is, that would account for the difference in readings, as I alluded to above, under certain conditions.

nancy is writing:

I cannot believe how much text you didn't delete when replying. You really should clip. It was ridiculous.

Happy New Year to you, too, Nancy! Is there anything else I can help you with today?

Right back atcha, just snip next time.

nancy

Since this thread is cross-posted to quite a few newsgroups, several where snippage is not customary, the above complaint is not justified. A better course of action for everyone would be to post only to your primary newsgroup interest. Janet

Interesting. I had some problems with my oven when I lined the shelves with quarry tile. The issue was I tiled the shelves from edge to edge, from front to back. This interfered with air movement to too great an extent. As a result, I re-tiled so that there is a 2" gap around the sides of the tiles on the bottom shelf, and a 1" gap on the top shelf. The temperatures seem to be much more even now.

Mike

Just to throw a monkey wrench into this conversation-- has anyone seen the tile "oven" in the Baker's Catalogue for the Christmas and January issues? It fits over the rack and on each side of the oven, and looks to be a huge heat sink. It also appears to literally fit into the oven permanently, and is very massive, (one buys the fixture which fits the best into your own oven). It looks like it would indeed make better bread, or pizza, (they give away a copy of Reinhart's "American Pie" with each fixture). But it is even larger than the quarry tiles. I just use the pan with the holes in the bottom. I don't have to mess with the oven, other than putting foil on the shelf below, and the oven works the same as always. I think sometimes technology can get ahold of one to the point where it loses it's edge, you know? But then, I am basically too lazy to work too hard at anything-- gw

Howdy,

I have seen the unit, but wondered why one would buy one when about $2.00 worth of firebricks would do the same thing...

All the best,

sort of my reaction, I must admit! gw