hello.. this is a good one.......my tenants upstairs seem to be constantly washing something, either a dishwasher or washing machine of maybe both....but monitoring the gas meter & Furness there gas doesn't move & there hot water tank never goes on but the Furness watching the gauges always drops in temp about 60 degrees in 9 sec. & the pipes clang & something is running upstairs....what I'm asking is, is there a way the may have tapped into the radiator pipes? water goes up 15 20 min later the toilet flushes & a lot of water comes doing...not the sump pumps are running more often even when it hasn't rained in a wile. Starting to smells like its backing up in the basement...please help ..thanks ...any info will help & put me in the right direction. TomaA

it's possible but not probable.
boiler water to wash dishes with would not give good results. not to mention that any white laundry would get stained rust colored..

Doesn't the boiler supply domestic hot water ?

thanks for replying.. I still cant figure out what there doing upstairs....I did a quick test by turning off the heat at the t-stat..everything turned off except I heard an electrical noise making contact with something & got nerves so when I turned it back on the whole burlding shook as water & air rushed thru the pipes...is the normal? any suggestions

sounds like that mean the system needs to be purged of air..