A temperature monitor helps identify the current temperature of an oven (eg. Wood fired pizza oven) or food within the oven. When cooking pizza it is imperative that the oven be extremely hot so as to crisp the bottom and add flavour throughout. For steak a thermometer can be used to judge the 'doneness' (eg. Rare, medium, well done) of the steak based on the internal temperature of the meat. Alternatively if a thermometer is not available the temperature of an oven may be gauged by an experienced oven user via the colour of the internal bricks, the heat felt physically, or of the time required for a small amount of flour placed on the oven hearthto turn brown.
Analogue thermometers are mechanical devices generally made of glass or stainless steel which give a read out on a dial to display the ambient temperature to an operator. For use with wood fired ovens these can be useful in easily and consistently identifying the temperature of the oven vault while the oven door is closed. If the door is open the thermometer is unlikely to give as accurate a reading. Additionally if the oven door is open it is likely that foods such as pizza will be the cooked food. For pizza the temperature of the hearth is more important that the vault, and thus a digital thermometer or experience based approach is recommended. For baking or slow roasting these types of thermometers are ideal. They generally cost around $10 from kitchen supply stores.
A number of different digital thermometers exist, however only a few are suggested for use with ovens or kilns. The k-type thermocouple probe thermometer is a device which has a probe that takes a reading and displays to a digital readout. The electronic device allows for the user to switch between °C and °F easily. When measuring the probe is pushed into a gap in the hearth or oven wall so as to achieve 6mm (1/4") penetration and an accurate temperature reading. These thermometers are generally recommended for pottery and industrial kilns rather than home use pizza ovens. More commonly are the infrared type thermometers which infer the temperature of a surface by measuring the infrared energy emitted by the object. These are sometimes called laser thermometers as they may utilise a laser in the process. The advantage of the infrared thermometers is that they allow a temperature reading without requiring the device to touch the surface directly. This allows a user to accurately judge the temperature of the oven hearth from a distance without potential for injury. For gauging the temperature of the oven vault the analogue type temperatures are recommended. These digital thermometers generally cost around $30 plus and are available from hardware or kitchen suppliers.