Last week the article covered pressure drop correction calculations. Today we offer you some handy charts to use for second glycol correction pressure drop. Example: I have calculated the water piping pressure drop through a chilled water system to be 80 feet using the System Syzer. Question: What is the pressure drop if I have 50% Ethylene Glycol/Water with temperatures of 45°F to 55°F? Answer: The average temperature is 50°F, so my factor is 1.47. [Read more…]... READ MORE
Question: I have selected my piping friction loss based on water, but I am pumping a glycol solution. What correction do I use? Answer: There are three glycol corrections when designing a hydronic or process cooling system; heat transfer correction, pressure drop correction, and pump curve correction. This R L Deppmann Monday Morning Minute defines the second of three glycol corrections. [Read more…]... READ MORE
Glycol correction factors were the subject of many of the last few R. L. Deppmann Monday Morning Minutes. While writing these articles, I thought about... READ MORE
Ask any test/balance or service technician in the hydronic HVAC world to convert PSIG to feet of head and the multiplier of 2.31 is the... READ MORE
The last couple of R. L. Deppmann Monday Morning Minutes introduced the BTUH corrections required when using glycol in hydronic heating and cooling systems.... READ MORE
In the last R. L. Deppmann Monday Morning Minute, I provided the BTUH correction factors for propylene glycol. We don’t want to play favorites so... READ MORE
We are all familiar with the BTUH formula (BTUH = GPM x ΔT x 500) used to calculate the gallons per minute (GPM) water flow... READ MORE
Last week the Monday Morning Minute article outlined the procedures we use during a check, test, and start-up of a B&G centrifugal pump. After converting from field gauge readings in PSIG to pump head in feet, there are several reasons why the results may be incorrect. The speed of the motor is different than the speed of [Read more…]... READ MORE
R. L. Deppmann Company Monday Morning Minutes addressed corrections to system GPM (gallons per minute) and system friction head during the last three weeks. Today we look at the pump selection. Centrifugal pump curves and the brake horsepower required changes depending on the fluid. In HVAC design we normally assume water is the pumped fluid. There are many times when the assumption is water, since there is no fluid mentioned on the schedule, yet we find a glycol makeup unit attached to the system. [Read more…]... READ MORE
Pump curves are based on water, but I am pumping a glycol solution. How will this affect the selection? This week we define the first of three glycol corrections. There are three glycol corrections when designing a hydronic or process cooling system; heat transfer correction, pressure drop correction, & pump curve correction. The first correction we’ll look at is heat transfer correction. When choosing chillers, boilers, heat exchangers, and terminal units, it is important to select them using the correct system fluid. [Read more…]... READ MORE