What do the buttons mean on my Roca BS-200 water heater?

have just moved into a house and have no idea what the buttons on the hot water boiler mean. there are three buttons, one looks like a hotwater one, one looks like the aircon blower and the other looks like an immersion button, but i have no idea and my water bills are really high!! does any one know about Roca boilers or universal symbols for boilers or something??? Thanks in advance|||I looked this water heater up on the web and found that they have dealers that carry this product. I would suggest that you call a plumbing company in your area and ask them about this product.I am not familiar with it sorry. Good luck