Domestic Hot Water: A Better Option?

From Buildings Magazine

The facts are frightening – especially since the problem can be avoided.

Consider this: As many as one in 10 patients hospitalized in the U.S. contracts an infection, according to the Wall Street Journal. That means nearly 2 million patients annually are infected by bacterium or other agents.

The end result?

The cost is nearly 100,000 deaths and $6.5 billion in overall losses.

Hand washing is a long-standing means of fighting such infections. Doctors, nurses, and other hospital employees, as well as patients and guests, constantly wash their hands typically using hot water to do so.

The supply of hot water — and the time in which it is delivered – makes an efficiently designed domestic hot water system paramount in a hospital. And that makes thermostatically controlled hot water flow control valves just what the doctors ordered. Unfortunately, these valves aren’t used as often as they should.

Normally, a domestic hot water system is manually balanced. Enough hot water flows at a rate to ensure that when a faucet is turned on, heated water is quickly delivered at a specified temperature set point – often 120 degrees Fahrenheit. To achieve this, the system is balanced with manually operated valves opened to produce the desired flow rate.

With multiple endpoints at sinks and showers, balancing usually requires two or more plumbing contractors. They must spend significant amounts of time between the hot water supply and the loop that services a particular bank of sinks or other fixtures, tweaking flow rates until the desired temperature is delivered.

A better method of achieving hot water balancing while using a fraction of the labor is to use a thermostatically controlled valve that opens and closes mechanically based on a temperature set point. For a hospital, this design has many advantages.

One major advantage is the cost reduction realized from the reduced flow. Using a thermostatically controlled valve only requires hot water flow when the temperature drops — not the constant flow that a manually balanced system needs.

Continue Reading…