Surround the pool heater with decorative landscape such as ornamental grasses or lush bushes. Plants like juniper or holly provide year-round coverage of the heater, while rose bushes or honeysuckle add more colorful options. Leave a gap in the plantings so that you can easily access the pool heater.
Install fencing around the pool heater to completely hide it from view, making sure to devote one side of the fence to a gate. Use a fencing style that matches your pool or yard fence for continuity of appearance. Stick to solid fence types, such as plastic, wood or metal pickets, or opt for a lattice fence where you can train plants to grow through, providing a level of natural coverage.
Build a solid wall around the pool heater with building materials that match the house. Install siding around the wall, cover the base wall with stucco, or use brick for a sophisticated appearance. Make a high wall that blocks the pool heater from view from all vantage points.
Build a plywood box with a hinged cover to hide the pool heater. Measure the distance around it and make it at least 2 feet bigger on either side to provide ventilation. Install a vent in the hinged top to provide additional ventilation. Slip the box over the heater when complete.