Building Management Systems – Pneumatic Controls
Popular back in the 1970’s and 1980’s, major concerns like Honeywell and Johnson Controls had many projects supplied with Pneumatic Controls, some or at least parts are still in service, especially damper and valve actuators.
Optimizing the torque in these actuators via an “E to P” device. that is, Electric to Pneumatic. This device converts a 0-10 volt DC signal to a pneumatic out put, say form 5 psi to 25 psi to drive the actuator.
Pneumatic Controls relied heavily on mechanical components
One of the greatest challenges with pneumatic controls, over time, was the internal wear and tear inside the field equipment. This wasn’t a big deal if the equipment was easy to get to, but, in some instances, especially in the older hospitals and medical centers, it could be difficult, very difficult.
Pneumatic Controls some times would have water in the lines
Not Every client could afford or wanted regular preventative maintenance for their Pneumatic Controls system.
Over time the air compressor serving the control system would collect water and this would end up in the pneumatic lines and the field components of the system.
Water would create the Upgrade Prompt
If enough water was in the system, it was pretty much a disaster and prompt an upgrade. the water would prompt service call after service call, making the ongoing maintenance and repairs of the system expensive.
Running the air compressor was also an adversity on the energy bill.
Considering an Upgrade from Pneumatic Controls to Digital Controls
Its is not always practical to upgrade from pneumatic systems to electronic or digital building management system in single sweep. Perhaps a staggered approach works. Or install the digital controllers first and use the “E to P” devices to minimize interruption, keeping existing pneumatic valves and damper actuators in service, at least for the near term.
Consider one plant room at a time, or a one floor.
Choices with Pneumatic systems
There are choices and options which can assist to improve energy management and HVAC air conditioning control without spending a fortune from your capital expenditure budget.
Consider the following:
- Fine tuning the system in the most cost effective areas, for example chiller and boiler control
- Consider just upgrading a part of the existing system to digital, making sure the system chosen is expandable and open protocol
- Install “E to P” and “P to E” devices (E = Electronic and P = Pneumatic) hence, making the system a hybrid
- Consider a maintenance agreement with a specialist in controls
Pneumatic Control System Upgrades
Why should you up grade your Pneumatic Control System to an electronic/Digital System?
The primary reasons are maintenance costs are increasing and energy costs are increasing.
Older Pneumatic systems have inherent errors which only expand over time, making energy losses and maintenance losses only increase. Digital systems are more accurate and easier to control your
HVAC plant and equipment.
Pneumatic heating Valve, difficult to replace the diaphragm, bulky and inaccurate. Notice there are not stab valves either side in this 35 year old installation
In a pneumatic system, there are fewer parameters to work with, consequently control valves might “hunt”, open/close modulations all day. This wears the valve stem “bonnet” quicker and consequently leaks.
Contact us for a free appraisal and quotation for an immediate upgrade.
We can offer specialized Refurbishment packages which include :
- Whole or part system installation
- “overlay” onto an existing System
- Minimal interruption to Building Occupants
- Night and after shift installers if required
- Re-use of existing equipment and wiring where possible
- Switchboard modifications by us (we’re licensed electricians)
- IP and internet costs included
- E-mail and/or SMS and /or Dialler alarm notification
- Extendable and flexible
- Energy Efficiency (Energy Audit prior & post installation)
BMS Upgrade Specification
We can assist you with a specification for tender purposes if you need also
Can We Help
If we can help, consider a free on site visit to discuss and review with you your options and opportunities