Show Sidebar
With the most recent advanced sensors, direct digital controls and computer system driven professional systems, buildings now can be completely automated and remotely managed.

Benefits of automation

Smart structures today utilize a building automation system or BAS and other systems to run HVAC, boilers, chillers, lights, elevators, constructing access fire security and other systems to attain the twin objectives of performance and convenience.

A BAS is defined here as a system of sensing units, pilot gadgets, reasoning elements, controllers, peripheral computer systems, and monitoring devices offering data to a main computer system for energy-efficient control of a structure's internal environment while likewise providing maximum tenant comfort and devices reliability.

BAS can deliver energy cost savings, convenience and maintenance/reliability advantages. These advantages can not be accomplished, nevertheless, unless the systems are correctly integrated. The system designer should expect and overcome the dangers outlined below.

Thermal shock

When boiler controls are incorrectly integrated with the BAS, thermal shock can take place in numerous ways.

The most typical is low return water temperature level. In a recent claim, a cast iron hot water boiler suffered a split area since of cold water returning from the system. The building was a single-story school, with parts of the structure far-off from the boiler space.

Throughout the fall, the BAS was configured to minimize the temperature level setpoint on weekends. Water in the zones serving remote locations cooled, and when the BAS tried to bring the building back to typical tenancy temperatures, a slug of cold water split the hot boiler areas.

The issue was resolved by putting timers on the zone valves to avoid the simultaneous opening. Controls also were added to keep a minimum floor through the longest loops during decreased temperature operations to maintain a minimum temperature.

In another case, a shop chain reported damage to boilers and cooling devices due to thermal shock when the BAS rotated between cooling and heating. Due to the fact that all the shop areas around the country were connected to a main BAS, this circumstance was made even worse.

The main BAS computer did not effectively enable shift from heating to cooling operation and vice versa, leading to boiler damage and business interruption.
Another form of thermal shock can happen in systems that use a three-way bypass valve. When managed by outside air temperature, these valves enable a high bypass, with reduced circulation through the boiler. This lowers the temperature level delivered to the loop, therefore saving energy.

The problem occurs when the control is so aggressive that the boiler water stratifies the exact same method water stratifies in a water heating system. In scenarios where the boiler is called on to provide just minimum input, the burner will cycle frequently. Given that the total temperature level is low, the metal is subjected too much greater tensions than intended or created for by the provider.

Thermal shock likewise has actually happened in boiler spaces having outside air inlet louvers managed by the BAS. Cold outside air getting in the boiler or devices space will chill the boiler. Thermal shock, freezing or condensation will occur if inadequate precautions are supplied.

Single-pipe heating and cooling systems location likewise based on thermal shock. Single-pipe systems one piping system for heating and cooling in some cases are chosen for low preliminary cost. Should both heating and cooling be called for within a short duration of time, there is an excellent chance that chilled water will be confessed into the boiler. Serious thermal shock will result.

Two-pipe systems utilizing separate piping circuits for heating and air conditioning do not completely remove this threat. If the BAS improperly sequences air managing devices and if both cooling and heating coils are in the very same device, air cooled by the refrigeration coils will cool the heating coils. This also will trigger cold water to return to the boiler.

Another more typical occasion happens when the BAS requires One Hundred Percent outside air to conserve cooling or heating energy. This typically occurs in shared areas of buildings that do not require heating or cooling for comfort. Spaces such as foyers, lobbies, corridors or huge conference spaces regularly get One Hundred Percent outside air to resolve indoor air quality concerns.

The heating coils in the air managing devices can be subjected to low temperature. When the boiler starts or the regional zone requires heat, the cold water will surprise the boiler.
In spaces needing really strict temperature and humidity controls, simultaneous operation of the heating temperature level control and cooling systems to lower humidity is needed. Careful attention to the programs of such heat/cool operation is needed to prevent the capacity for cold water return to a hot boiler.


When boilers cool below the humidity temperature level of the combustion products, flue gas condensation will occur during the boiler warm-up, causing rust on fireside surfaces, breeching and stacks.

Corrosion is another leading cause of boiler accidents. If the BAS is set to keep boiler temperature level at or slightly above the flue gas dew point, much of the deterioration can be prevented.

Boiler start-up

When a boiler is very first started from a cold condition, both the metal and water are cold. If the boiler is designed to adjust shooting rates in response to pack changes, it is extremely important to heat the boiler slowly.

The metal structure should be permitted to gradually soak up the stresses that develop as the metal broadens with temperature level. A lot of boiler makers consist of low fire hold into their boiler manages to provide boiler warm-up. BAS programs should not compromise this security by premature transfer to high shooting.

Numerous boilers (Modular)

For buildings with modular or several boilers, the dangers gone over above are more difficult to deal with. In such cases, BAS programming should acknowledge the practical limits of boiler operation for all devices.

Other concerns

In addition to the mechanical elements already discussed, there can be other concerns with control system integrity. A BAS is consisted of sensing units, pilot gadgets, logic elements, controllers, peripheral computers and monitoring equipment. All these gadgets are vulnerable to some of the following conditions.

Electrical transients

A number of claims have actually recently been reported including failure of electrical and electronic gadgets triggered by electrical transients. Common interruptions originate from lighting, internal power variations, harmonics and electric utility issues. Without appropriate security, an otherwise harmless power variation can result in damage to the boilers if the BAS fails.

Major utility power issues are irregular. Lighting arresters, surge defense and present controls have actually made power in the United States extremely dependable. One source of localized disturbances is not unusual, however.

When utilities attempt to manage power aspects by compensating for inductive loads with big capacitor banks, short period voltage collapse a couple of cycles can take place. When the capacitor bank is engaged, the present inrush causes the voltage to sag, which can trigger localized disruptions in the power system.

Boiler/BAS Solutions

CONSIDER THESE RECOMMENDATIONS to address typical boiler problems connected to BAS:

Thermal shock

Prevent cold water return by installing three-way blending valves as a method of limiting the boiler inlet water temperature. Think about a little blending pump to avoid temperature level stratification in the boiler.

The Green Book leading industrial, commercial, and consumer directory in Singapore provides trusted list of companies, suppliers, and distributors that offers high quality building controls.

Basic Listings

Adaptive Control Systems Pte Ltd

48 Toh Guan Rd East #04-100 Enterprise Hub S(608586)

Adaptive Control Systems Pte.Ltd.(ACSPL),was incorporated in 1998, to cater for the increasing demand for Building Management systems (BMS) ...

Azbil Singapore Pte Ltd

2 International Business Pk #04-12 The Strategy Tower 1 S(609930)

Barcol-Air Engineering Pte Ltd

30 Loyang Way #03-06 Loyang Ind Est S(508769)

Power Management, Generation & Distribution Controls Engine Starting, Monitoring & Control Systems Power & Facility ...

Building Automation Components Pte Ltd

Blk 531 Up Cross St #04-56 Hong Lim Complex S(050531)

Since its establishment in 1996, Building Automation Components Pte Ltd is now one of the leading suppliers and distributors of wide range ...

Carlo Gavazzi Automation Singapore Pte Ltd

61 Tai Seng Ave #05-06 Crescendas Print Media Hub S(534167)

George Fischer Pte Ltd

11 Tampines St 92 Tampines Biz-Hub S(528872)

Leaptron Engineering Pte Ltd

17 Tai Seng Dr #06-01 Yew Lee Bldg S(535221)

At Leaptron, helping partners and customers succeed and grow is what we do best – with industrial automation control and information ...

United Marketing & Intertrade

Blk 22 Woodlands Link #04-17 Woodlands East Ind Est S(738734)