Nevermind I take back the wrench idea. I just looked again and saw the placeholder image of a "plumber working" so that should give it away. Second the logo is fairly big and clearly says plumbing and heating so if you keep you find a good picture for that placeholder image it should be fine.

EDIT: the phone number is very hard to read in the top right. That is something that should be extremely important to a plumber and they're customers need quick acces to it. I realize you want it to look good but his customers probably wont notice or care. Maybe add a dot or just old fashioned dashes. Second I can't tell if that is their address or Gorgi's. That is very confusing and if I were a customer I would probably leave because I couldn't figure that out. Most customers will probably hardly even flip through the site they just go "they're a plumber, site looks good, how do I call 'em" So maybe add their number on the image of the plumber.