I recently visited a school mechanical room and was asked about the relationship between the makeup pressure reducing valve setting and the expansion tank pressure …
Centrifugal Pump Gauge Readout: Adjustments to Balancing for Glycol Temperature
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 …
Centrifugal Pump Gauge Readout Corrections for Hydronic Glycol Systems
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 …
Centrifugal Pump Gauge Readout Corrections-Velocity Head Corrections
We recently had an inquiry from an engineer who was concerned about pump operation compared with the submitted pump curve. It appeared from the balance …
The Department of Energy (DOE) Pump Standards – Now is the Time to Choose
The Department of Energy (DOE) pump standards goes into effect on January 27, 2020. This affects projects you are sending out to bid right now! …
Piping Pressure Drop Correction Factors when using Glycol in Hydronic HVAC Systems
The last couple of R. L. Deppmann Monday Morning Minutes introduced the BTUH corrections required when using glycol in hydronic heating and cooling systems. …
BTUH Correction Factors when using Ethylene Glycol in Hydronic HVAC Systems
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 …
Propylene Glycol BTUH Correction Factors in Hydronic HVAC Systems
We are all familiar with the BTUH formula (BTUH = GPM x ΔT x 500) used to calculate the gallons per minute (GPM) water flow …
Condensing Boilers and Air Handing Unit (AHU): Hydronic Hot Water Coil Return Temperature
Correction to my 8-26-19 blog. In the rush to get on vacation I messed up on my math. This is corrected. Thank you to Tom …
Domestic Water Heaters: Plate Heat Exchangers and Dual Return Condensing Boilers
Gas-fired storage type domestic water heaters are the norm in commercial and institutional buildings. Walk into any mechanical room of a larger complex and you …