I'm installing a secondhand model ST3100 and it all seems pretty straightforward - the mains hot and cold come in and are distributed to the washing machine and/or the tub taps. This piping is all copper. However there are also three plastic hoses (with white braid inside) hanging down at the back - one from each of the tub taps and one from the faucet. I can't figure out what these are for and how to connect them. Perhaps they are redundant and need to be blanked off?

I have downloaded the manufacturers pdf's and tried calling them but have not got the answer. Would appreciate any advice.