How to set up proper steam condensate piping

Inside Process: Steam condensate systems must have proper piping to ensure optimal performance.

01/08/2017


Figure 1: All steam condensate systems for commercial, industrial, and any other application need to have proper piping. Courtesy: Cummins-WagnerAll steam condensate systems for commercial, industrial, and any other applications need to have proper piping (see Figure 1). When a steam-to-water heater with a modulating control valve is used, the condensate from the float and thermostatic trap should not be lifted (see Figure 2), or else the system won't be able to control the temperature. That's because the pressure in the coil will be too low to push the condensate up to an overhead return.

When this happens, the heat from the condensate will transfer through the coil into the hot water, even though the controls have sensed the water is at or above its setpoint. When there is an overhead condensate return, provisions should be made for gravity to drain the condensate to a lower receiver and pump the condensate to the overhead return. 

Heater operation

A heater is expected to operate with 15 PSIG at the inlet of the control valve. There is a 10-ft lift from the trap outlet to the overhead return. The 10-ft column of water exerts a back pressure on the trap outlet of 4.5 PSIG.

A typical pressure drop across a temperature control valve is 30% (about 4.5 PSIG) when fully open, so 10.5 PSIG is left to enter the coil. As the steam condenses in the coil, the pressure will continue to drop. When the it drops below the back pressure, the heater will stall. The sensor then will see a drop in temperature and begin to open the steam valve, so both steam and condensate can begin to flow again.

Figure 2: When a steam-to-water heater with a modulating control valve is used, the condensate from the float and thermostatic trap should not be lifted. Courtesy: Cummins-WagnerThis process causes the water temperature to increase and the valve to close. The high temperature (HT) condensate will stop flowing, and the heat from the HT condensate will transfer to the domestic water side. This causes an uncontrolled temperature rise, possibly to unsafe levels.

Richard Goins has more than 39 years of industry experience. He began his career with Cummins-Wagner as a sales engineer. In 1994, he started Environmental Air Products (EAP), an HVAC division of Cummins-Wagner. As general manager of EAP, he defined the company's purpose and goals to expand on Cummins-Wagner's market segment. In 2000, he was asked to manage the Engineered Services Group (E3), which is responsible for providing technical support to the engineering community. In addition, Goins provides training and educational seminars to external and internal clients to further develop their professional growth. He is also a member of ASHRAE, ASPE, and CASHE. Edited by Jack Smith, content manager, CFE Media, Control Engineering, jsmith@cfemedia.com

MORE ADVICE

Key concepts

  • Steam condensate systems for commercial and industrial applications must have proper piping.
  • A typical pressure drop across a temperature control valve is 30% when fully open.
  • When the pressure drops below the back pressure, the heater will stall; the sensor then will see a drop in temperature and begin to open the steam valve, so steam and condensate can begin to flow again. 

Consider this

When was the last time your plant conducted a steam trap audit?



The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by Control Engineering subscribers. Vote now (if qualified)!
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Maximize ROI with integrated control system approach; Microcontrollers vs. PLCs; Power quality; Accelerate and rewire IIoT; Traits for excellent engineers
HMI effectiveness; Distributed I/O; Engineers' Choice Award finalists; System Integrator advice; Inside Machines
Women in engineering; Engineering Leaders Under 40; PID benefits and drawbacks; Ladder logic; Cloud computing
Programmable logic controllers (PLCs) represent the logic (decision) part of the control loop of sense, decide, and actuate. As we know, PLCs aren’t the only option for making decisions in a control loop, but they are likely why you’re here.
This digital report explains how plant engineers and subject matter experts (SME) need support for time series data and its many challenges.
This article collection contains several articles on how advancements in vision system designs, computing power, algorithms, optics, and communications are making machine vision more cost effective than ever before.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Control room technology innovation; Practical approaches to corrosion protection; Pipeline regulator revises quality programs
Cloud, mobility, and remote operations; SCADA and contextual mobility; Custom UPS empowering a secure pipeline
Infrastructure for natural gas expansion; Artificial lift methods; Disruptive technology and fugitive gas emissions
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by Control Engineering subscribers. Vote now (if qualified)!
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Maximize ROI with integrated control system approach; Microcontrollers vs. PLCs; Power quality; Accelerate and rewire IIoT; Traits for excellent engineers
HMI effectiveness; Distributed I/O; Engineers' Choice Award finalists; System Integrator advice; Inside Machines
Women in engineering; Engineering Leaders Under 40; PID benefits and drawbacks; Ladder logic; Cloud computing
Programmable logic controllers (PLCs) represent the logic (decision) part of the control loop of sense, decide, and actuate. As we know, PLCs aren’t the only option for making decisions in a control loop, but they are likely why you’re here.
This digital report explains how plant engineers and subject matter experts (SME) need support for time series data and its many challenges.
This article collection contains several articles on how advancements in vision system designs, computing power, algorithms, optics, and communications are making machine vision more cost effective than ever before.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Control room technology innovation; Practical approaches to corrosion protection; Pipeline regulator revises quality programs
Cloud, mobility, and remote operations; SCADA and contextual mobility; Custom UPS empowering a secure pipeline
Infrastructure for natural gas expansion; Artificial lift methods; Disruptive technology and fugitive gas emissions
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by Control Engineering subscribers. Vote now (if qualified)!
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Maximize ROI with integrated control system approach; Microcontrollers vs. PLCs; Power quality; Accelerate and rewire IIoT; Traits for excellent engineers
HMI effectiveness; Distributed I/O; Engineers' Choice Award finalists; System Integrator advice; Inside Machines
Women in engineering; Engineering Leaders Under 40; PID benefits and drawbacks; Ladder logic; Cloud computing
Programmable logic controllers (PLCs) represent the logic (decision) part of the control loop of sense, decide, and actuate. As we know, PLCs aren’t the only option for making decisions in a control loop, but they are likely why you’re here.
This digital report explains how plant engineers and subject matter experts (SME) need support for time series data and its many challenges.
This article collection contains several articles on how advancements in vision system designs, computing power, algorithms, optics, and communications are making machine vision more cost effective than ever before.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Control room technology innovation; Practical approaches to corrosion protection; Pipeline regulator revises quality programs
Cloud, mobility, and remote operations; SCADA and contextual mobility; Custom UPS empowering a secure pipeline
Infrastructure for natural gas expansion; Artificial lift methods; Disruptive technology and fugitive gas emissions
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me