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 Subject: Tumble dryer operating temperature Category: Science > Physics Asked by: dryerman-ga List Price: \$50.00 Posted: 16 May 2006 09:30 PDT Expires: 15 Jun 2006 09:30 PDT Question ID: 729373
 ```What temperature is the inside of an operating tumble dryer? I am trying to understand the range of temperatures that an item (particularly PVC) inside a tumble dryer might reach after, say, 120 minutes on the "hottest" cycle. I know that this will vary with the condition of the machine so a good answer would give me a "typical" temperature and also the temperature if all the lint traps etc. were blocked so that the machine was over-heating.```
 Subject: Re: Tumble dryer operating temperature Answered By: leapinglizard-ga on 16 May 2006 11:15 PDT Rated:
 ```Dear dryerman, Under normal operating conditions, the hot air blown into a clothes dryer's tumbler reaches a temperature of about 175 degrees Celsius. Another air temperature of interest is at the tumbler intake. The air temperature in this area rose to about 175°C during normal operation [see Figure 1]. Appliance Magazine: Detection of Abnormal Operating Conditions in Electric Clothes Dryers http://www.appliancemagazine.com/amag/editorial.php?article=521&zone=1&first=1 If the lint traps are blocked and the thermostat fails, the resulting unregulated temperatures have been shown to exceed 400 degrees Celsius. In FY 2002, U.S. Consumer Product Safety Commission staff completed a test program to evaluate residential electric clothes dryers under various test conditions. The test program included measurements of temperature and airflow characteristics for different electric clothes dryer designs under normal operating conditions and conditions of partially-blocked and fully-blocked exhaust ducting. [...] 3.2.1 Normal Operation (Unblocked Exhaust Vent) When the dryers were tested with an unblocked exhaust vent, similar temperatures ?- the intake air temperature into the heater, the heater housing temperature, the intake air temperature into the blower, and the exhaust vent temperature -? were measured among all dryer designs. [...] 3.2.2 Partially-Blocked and 100%-Blocked Conditions Each dryer design reacted slightly differently when the exhaust vent was partially blocked and/or 100% blocked. [...] Figure 81 shows the range of highest to lowest maximum temperatures at the intake into the tumbler for each test condition. The temperature curves shown in this graph are similar to those for the heater exhaust (Figure 77), except that the maximum temperature measured when the exhaust vent was fully blocked was lower ? approximately 400°C. U.S. Consumer Product Safety Commission: Final Report on Electric Clothes Dryers and Lint Ignition Characteristics http://www.cpsc.gov/library/foia/foia03/os/dryer.pdf A diagram on page 105 of the CPSC report (page 118 of the PDF document) shows the various places where temperatures can be measured inside a dryer. Because a sensor cannot be placed inside the tumbler itself, the nearest location for measuring the temperature inside the tumbler is T6, the tumbler intake. It is here that the normal temperature of about 175°C and the maximum temperature of 400°C were observed. It has been an interesting challenge to answer your question. If you have any concerns about the accuracy or completeness of my research, please advise me through a Clarification Request and allow me the opportunity to fully meet your needs before you rate this answer. Regards, leapinglizard Search strategy: clothes dryer temperature degrees ://www.google.com/search?q=clothes+dryer+temperature+degrees ://www.google.ca/search?q=laundry+dryer+temperature+limit laundry dryer temperature limit``` Request for Answer Clarification by dryerman-ga on 18 May 2006 07:35 PDT ```Thank you leapinglizard. Sorry for the late response but the auto-notify seems not to be working so I wasn't aware anyone had answered. I had already come across the US Product Safety commission report (although the Appliance Magazine article was new to me). However, it was particulalrly the temperature of items inside the dryer rather than the air temperature entering and exiting that is of interest to me. Maybe air temperature is the best I can get but I was hoping for something more. Surely fabric manufacturers have tested to see how hot their clothes get before they shrink/ruin etc.?``` Clarification of Answer by leapinglizard-ga on 19 May 2006 13:15 PDT ```The items in a dryer cannot reach a higher temperature than the air surrounding them, so at least you have an upper limit. The air temperature inside the tumbler must be somewhere between the intake and exhaust temperatures. You raise an interesting point about the heat resistance of fabrics, but I'm afraid I haven't found any exact numbers on this. leapinglizard```
 dryerman-ga rated this answer: `The answer was useful but did not answer the specifics of the question.`

 ```Domestic dryers go up to about 90 deg C. That's a regulated temperature, so blockages shouldn't have much effect. If the thermostat fails I suppose all bets are off! Ian G.```
 ```My guess is an error has occured. Some faberics would be badly damaged by 175 c and nearly all faberics by 400 degrees c = 753 degrees f. Painful burns would reward the person who tried to remove the clothing just before the cool down cycle. The 90 degrees c = 194 degrees f. seems more reasonable. Neil```