Pouyan,
It is possible; the definition is not done at the building level in Type56 but by implementing a water draw component as well as the rest of the components that make up the water heating system (tanks, pumps, pipes, draws, solar collectors, boilers, etc.). There are any number of ways that the water draw can be defined. If you have access to the TESS Utility library you will find a pair of water draw profile components called Type1243 and Type1251. If you have access to the TESS Applications library there are some forcing function components in there that are a possibility. Alternatively you could set up a Typw14 forcing function or read known water draws from an external data file using Type9.
kind regards,
David