Array ( [0] => [1] => household_heating [2] => roof_heating [3] => ) Array ( [0] => [1] => household_heating [2] => pipes_heating [3] => ) Array ( [0] => [1] => household_heating [2] => platform_heating [3] => ) Array ( [0] => [1] => household_heating [2] => floor_heating [3] => )