Swimming Pool Pump / Heaters The critical process in a swimming pool is to maintain the chemical purity and quality and the temperature of the water. Water is moved through the filtering system by small pumps and a small water heater is used to heat the pool water. Pool equipment maintenance can be a low priority, yet due to the harsh chemical environment, pumps and related equipment are subject to premature failure and breakdown. © 2004 The Hartford Steam Boiler Insurance and Inspection Company.     All rights reserved.