My son has a condensing tumble dryer and I get him to bottle up the water from that for use in the steam iron and car cooling system. An electric dehumidifier in the garage (if you are lucky enough to run one) presumably supplies the same condensate.
Oh I never thought it would be as good as ionised water. My dehumidifier goes straight down the drain but I could ask it to fill a bucket or two..... Any chemists on here???