I have often pondered this,http://www.outdoorwoodfurnaceparts.biz/new_page_8.htm
I read somwhere an electric clothes dryer heated to about 150 F, I think that would be hard to get to with 180 F hydronic boiler but I'm sure clothes would dry cooler than 150 F but it would take longer.
Speed Queen built at one time comercial dryers that used steam for a heat source, 120 PSI and 15 PSI the 120 PSI unit had one heat exchanger, the 15 PSI unit had two. I understand some were brought to the villages on the North Slope of Alaska and tried with hot water in the 15 PSI heat exchanger, with poor results.
This is a heat exchanger sold with the idea that you could retrofit your current dryer.
I seam to remember somone on this site recomending a certain brand of dryer because the shape of the electric heating element space was an easier fit for a radiatior.anyone heating their clothes dryer with water?
And LsFarm mentions 120 F in this postWater to Water heat exchanger ?
dryerCoal fired clothed dryer?