Plumbing Topic: Domestic Water Recirculation Systems Part 7

Norm Hall Domestic Water Recirculation, Mixing Valves, Monday Morning Minutes, Plumbing System Design

“Addition of a Mixing Valve” During the last 6 weeks, the R. L. Deppmann Monday Morning Minutes concentrated on re-circulation systems where the supply temperature to the system was the same as the outlet temperature of the water heater. Today we will examine the addition of a Lawler master mixing valve in the system.

Double Wall Plate Heat Exchangers

Norm Hall Double Wall, Double Wall, Heat Exchangers, Heat Exchangers, Monday Morning Minutes, Plate Type, Plumbing System Design

The Monday Morning Minutes of the last two weeks introduced some differences between plate heat exchangers. Two of the products featured were the double wall plate & frame and double wall brazed plate heat exchangers. We have received many calls regarding these models and Michigan and Ohio plumbing codes. The plumbing code is very specific in its

Centrifugal Pumps and Pump Curves for HVAC and Plumbing Systems

Norm Hall Curves, Monday Morning Minutes, Pumps, Selection and Specification

Centrifugal pumps are the “heart” of hydronic heating, cooling, and plumbing systems. Over the next few weeks, the R. L. Deppmann Monday Morning Minutes features some basic and advanced pumping topics. Let’s start with a quick review of the information contained on the pump curve. For our example, we will use an ITT Bell and Gossett model 1510 end suction base mounted centrifugal pump model 5E with a nominal speed of 1750 RPM. The horizontal axis is flow rate in GPM or gallons per minute of water. [Read more…]