How Water Quality and Seal Selection Affect Hydronic Systems
The water quality in hydronic systems directly affects the performance and life expectancy of the components in the systems. Total dissolved solids (TDS) and pH …
Bell & Gossett Part Load Efficiency Value (Part 5): BTUH Load Output vs. Percent of Flow Tolerance
The last four segments of the R. L. Deppmann Monday Morning Minutes introduced the valuable PLEV tool from Bell and Gossett. The part load efficiency …
Steam Vent Operating Pressure
I have a 15 psig steam system which operates at about 7 PSIG most of the time. Is the Hoffman Main Steam Vent Model 75 appropriate for this application with its listed 15 psig maximum? [Read More…]
Air Separator Location in Hydronic Systems
R. L. Deppmann is offering another series of seminars, this fall, which are centered on “Energy Savings and ASHRAE 90.1 and 189.1 standards”. During a couple of the first 7 seminars, the question of the air separation location sparked a short discussion. Let’s review the response in this Monday Morning Minute. [Read More…]
Triple Duty® valves on your variable speed hydronic pumps
Bell and Gossett triple duty valves have, for decades, provided a cost effective way to assure there is a non slam check, balance, and shutoff valve on the discharge of your hydronic pump installation. These valves are used to throttle excess head and, therefore, should not be oversized. B&G offers these installation friendly valves in traditional full port model (3DS-S) and in a reduced port version (3DS-B) [Read more…]
Strategies for Water Use Efficiency – Cooling Towers – Part II
In this issue, we will discuss blow down and cycles of concentration. In addition to water emissions caused by evaporation and drift, cooling towers require blow-down to control the levels of dissolved minerals re-circulated in the cooling tower. These losses are offset or balanced by make up water to both maintain the level of water in the tower and more importantly, [Read more…]
A Great Way to Fill the Piping Systems – Cooling Tower Pumps and Piping – Part 9
The Xylem Bell and Gossett manual TEH-1209 has a great detail for filling the tower water system piping. Many times the cooling tower pump is used to take water from the tower pan and fill the condenser and piping system. This can lead to pump problems due to the large flow rate of the pump compared with [Read more…]
Pump Suction Piping Rules – Cooling Tower Pumps and Piping – Part 8
Traditional hydronic piping system designers use tools such as the Xylem Bell & Gossett System Syzer for pipe sizing. You may find this program at http://completewatersystems.com. Tower manufacturers, the Hydraulic Institute (HI), and Bell and Gossett all suggest lower velocity for pipe selection in cooling tower pump suction piping. Bell and Gossett has several pipe sizing suggestions [Read more…]
Pump Suction Piping Rules – Cooling Tower Pumps and Piping – Part 7
This week we continue our suggestions for tower pump suction piping. In order to minimize problems with air, noise, and NPSH at the tower pump, Bell and Gossett recommends you try to keep high pressure drop devices out of the suction piping and also keep the velocity low. Let’s examine high pressure drop device this week. [Read more…]
Pump Suction Piping Rules – Cooling Tower Pumps and Piping – Part 6
Over the last several weeks we discussed the feared NPSH and showed it is rarely an issue at design conditions. More often than not, noise and pressure problems are caused by air in the suction piping system. The suction pipe, in many cooling pumping systems, is under very little pressure. In fact, the suction of the pump could be under a vacuum. [Read more…]