Now that the U.S. Department of Energy (DOE) has published the first ever Energy Conservation Standards for Pumps, let’s take a look at some of …
New Pump Efficiency Standards Part 1: They’re Here, Now What?
Heat pumps have them. Air conditioners have them. Even light bulbs have them. And now, for the first time in history, clean water pumps have …
The Day Hunter’s Curve Didn’t Look Safe: A Pressure Booster Story
The R. L. Deppmann Startup and Warranty Team team receives a lot of interesting calls about systems that aren’t working properly. In this case, our …
Hydropneumatic Tanks for Variable-Speed Pressure Boosters, Part 3
In the last RLD Monday Morning Minute I described the pre-pressurized tank sizing for constant-speed booster systems. There are those who say, “My pressure booster system is …
Hydropneumatic Tanks for Variable-Speed Pressure Boosters, Part 2
In last week’s RLD Monday Morning Minute, I described a brief history of pressure-boosting systems and the introduction of the pre-pressurized tank. This week we continue …
Hydro-pneumatic Tanks for Variable Speed Pressure Boosters, Part 1
Possibly only engineers, like myself, can appreciate controversy in plumbing system design. The use and sizing of storage tanks in variable speed pressure boosters is …
Where Cavitation Begins – Cooling Tower Pumps and Piping
Last week the R. L. Deppmann Monday Morning Minute defined NPSHR, and ended with the Hydraulic Institute (HI) definition as the absolute pressure that will cause the total head of the pump to be reduced by 3%, due to flow blockage from cavitation”. Of importance is the fact that it does not say that NPSHR is where cavitation begins.
Plumbing Topic: Domestic Water Recirculation Systems Part 4
The last three articles outlined pump selection in domestic water recirculation systems. In general, these systems have low flow and low head pumps. What happens in a high rise with pressure reducing valves (PRV) in the hot water supply? The pressure reducing valve introduces a fixed pressure drop which must be added to the calculations.