Guide To Pool Heating

Page 5 of 51

A main drain was located at the bottom of the pool where, in theory, particulate matter

would gravitate downward and into the main drain. This “collected” particulate matter (dirt, sand,

etc.) would then be trapped by the filter and clean water returned to the top of the pool via the

“return lines.”If a heater was employed, it didn’t matter much because energy was cheap in the

early years when residential swimming pools were introduced.

What’s wrong with the traditional design of the pool?

The traditional design doesn’t work out the way it was intended. First, the dirt, debris

and other particulate matter does not all reach the main drain. Decades of experience

show that an area of about 2-3 feet around the main drain will stay clean from the suction while the

pool owner must vacuum the rest of the pool’s bottom to ensure its cleanliness.

Second is the fact that inexpensive energy is a past luxury no longer

available.Pool owners heating with fossil fuels or electricity can pay hundreds of dollars each

month in energy costs.

Third, and again, is the fact that heat rises even if particulate matter sinks!

Illustration 1, labeled “NORMAL FLOW,” shows the plumbing of a typical pool. This is a

side view of a typical pool. The pool’s main drain is shown on the bottom and the pool’s return

lines are represented by the three black circles at the top.

Illustration 1.

NORMAL FLOW