Changeover Time is Coming

After one of the coldest winters in recent memory, the heating to cooling changeover is right around the corner. Here are some tips for making the changeover this year.

 

1)      During the shoulder season when heating may be required, Make Up Air units that are fed by Primary Boilers can be left in a heating mode while the fan-coils in the suites are switched over to cooling. With a cooler Spring appearing likely, this will allow you to provide some heat in the corridors while providing cooling insuite.

 

2)      Glycol – make sure that when draining coils of glycol to recover all of the glycol in clean storage containers. Do not let the glycol flow into the building mains.

 

3)      Basement Loops (Miscellaneous Heating Loops) that are fed from the Heating / Cooling Mains need to be manually shut down during the summer to prevent condensation in enclosed spaces.

 

4)      Do an inspection of the Cooling Tower well before your changeover date. With the ice storm, it is possible that parts of the Tower may have experienced some damage due to heavy ice.

 

5)      Make sure that outside, electrically heated areas are shut down for the summer or that the controlling thermostats are set to a minimum set-point a couple of degrees above freezing.

 

6)      Remember to call Provident Energy during your changeover. Unless the Energy Management System is commanded to the cooling mode, HVAC systems will not operate properly.

Building Automation System Take–Overs

Not all Building Automation Systems (also known as Energy Management Systems) are the same. There is a wide range of manufacturers and installers with different control abilities.

As part of our free energy assessment, we often inspect existing Building Automation Systems. Regardless if the Building Automation System was installed during the construction of the building or if the System was installed as a retrofit, there are often areas that are either not controlled or not controlled very well. In many cases, the existing Building Automation System can be upgraded via the implementation of additional Variable Frequency Drives and leak/flood detection.

Provident Energy utilizes a Siemens Apogee Building Automation System that can be remotely accessed via the internet. Most Building Automation Systems are owned by the Condominium Corporation and they are free to choose any Energy Management company to monitor their system. The take-over should not involve a full re-installation of the Building Automation System. For any System, the main control panels can be replaced and in most cases the existing wiring, sensors and conduits can be re-used (the initial wiring is generally the most costly and labour intensive step).

As mentioned earlier, we find many existing Systems leave room for improvement. For example, the Domestic Hot Water System may have a flat temperature set-point for the entire day and night. Or, the make-up air handling units may have VFDs that fluctuate only between 85% and 95%, 24 hours per day – whereas these units could be slowed down during non-peak hours. Provident Energy can implement additional control algorithms for existing Building Automation Systems and we can usually enhance overall energy savings by 4%-7%.

Another important feature of Provident Energy’s Building Automation System is our Monitoring Service. Your building’s system will be monitored 24/7 offsite by Provident Energy’s team of highly skilled technicians for both critical systems alarms and overall system optimization. This ensures that any issues that may arise within the buildings critical components will be diagnosed by technicians and relayed back to the site staff. Early diagnosis of such issues helps to prolong the life of your critical components, and also helps to ensure that the residents comfort isn’t compromised in the process.

Building Automation System Take–Overs

Not all Building Automation Systems (also known as Energy Management Systems) are the same. There is a wide range of manufacturers and installers with different control abilities.

As part of our free energy assessment, we often inspect existing Building Automation Systems. Regardless if the Building Automation System was installed during the construction of the building or if the System was installed as a retrofit, there are often areas that are either not controlled or not controlled very well. In many cases, the existing Building Automation System can be upgraded via the implementation of additional Variable Frequency Drives and leak/flood detection.

 
Provident Energy utilizes a Siemens Apogee Building Automation System that can be remotely accessed via the internet. Most Building Automation Systems are owned by the Condominium Corporation and they are free to choose any Energy Management company to monitor their system. The take-over should not involve a full re-installation of the Building Automation System. For any System, the main control panels can be replaced and in most cases the existing wiring, sensors and conduits can be re-used (the initial wiring is generally the most costly and labour intensive step).

As mentioned earlier, we find many existing Systems leave room for improvement.  For example, the Domestic Hot Water System may have a flat temperature set-point for the entire day and night. Or, the make-up air handling units may have VFDs that fluctuate only between 85% and 95%, 24 hours per day – whereas these units could be slowed down during non-peak hours. Provident Energy can implement additional control algorithms for existing Building Automation Systems and we can usually enhance overall energy savings by 4%-7%.

Another important feature of Provident Energy’s Building Automation System is our Monitoring Service.  Your building’s system will be monitored 24/7 offsite by Provident Energy’s team of highly skilled technicians for both critical systems alarms and overall system optimization. This ensures that any issues that may arise within the buildings critical components will be diagnosed by technicians and relayed back to the site staff. Early diagnosis of such issues helps to prolong the life of your critical components, and also helps to ensure that the residents comfort isn’t compromised in the process. 

 

 

 

For more information or to book a free energy assessment, please contact the sales department at Provident Energy at 416-736-0630, extension 5 or visit our website www.pemi.com

Tech Corner: Alarm Monitoring – When, Why and How?

Energy Management Systems installed by Provident Energy are designed and programmed to generate alarms that are sent over the internet to servers located in our offices that sort, prioritize and relay these alarms to our Technicians.

Broadly speaking, there are two types of alarms: Critical and Non-Critical Alarms. Critical Alarms are those alarms that are classified as affecting in-suite comfort. This would include things like Chiller Operation, Heating System, Domestic Hot Water, and Leak Detection Alarms. In these cases, these alarms are relayed to a primary Technician who is responsible for responding to these alarms.

When the Technician receives these Critical Alarms, they immediately start to investigate. This is needed to determine the nature of the Critical Alarm – has the building recently recovered from a power failure, or was the water shut off to the building for repairs, are storm and wind creating problems for boilers? After determining the nature of the alarm, the Technician will often need to contact your site staff in accordance with the contact procedures Property Management has put in place. Usually, this is a call to Security, who also has a contact procedure in place. 

Non-Critical Alarms are for those conditions which do not immediately affect in-suite comfort. An example of this might be a corridor fan. There is little advantage to calling in contractors on over-time to fix something that can wait until the next business day. In these situations, we do just that – wait until the next business day to contact your office.

Many alarms come into our servers that are used by our Technicians to help diagnose and repair problems in your building. Examples of this might include Coil Temperature Alarms. While the building might not be feeling too hot or too cold, an alarm could indicate that an Air Handling Unit is struggling to maintain the proper air temperature or that a supply water temperature might be too low. In these cases, our Technicians will take the steps necessary to tune your building and work with your contractors and building staff to optimize operation.

 

Make Up Air Units and Variable Frequency Drives

Corridor Fresh Air Units or Make-Up Air Units (MUA) are found in virtually all High Rise Multi-Residential Buildings. Older buildings, including rental properties, often have these units with no heating or air conditioning of the air introduced into the building. In newer buildings and in virtually all condominiums, these units do provide heating and cooling of the fresh air.

The purpose of the MUA units is threefold. First, the units slightly pressurize the building in order to prevent infiltration of outdoor air through the building envelope. Second, the units provide, as the name implies, ‘make up air’, to replace air that has been exhausted from the building by in suite exhaust fans. The third purpose is to provide for ‘air changes’, or fresh air for comfort and respiration.

The Canadian Mortgage and Housing Corporation (CMHC) have done numerous studies on make up air units, and have found some very interesting results. One of the things that were found was that this air often leaks through the building envelope in unintended ways.Air can leak through door openings, envelope penetrations, elevator shafts, stairwells, and other places where the air can find its way directly to the outside. The result is that Fresh Air Units can be tremendous energy ‘wasters’. When fans are sized during the construction phase, they are often sized using the assumption that a certain number of exhaust fans will be running at the same time. This is referred to as the diversity factor. Clearly, at night and at other off-peak times, the actual use of exhaust fans will be well below the diversity factor used to size the fans.

One excellent solution is the use of Variable Frequency Drives (VFD). The fan can be operated on a time of day schedule, speeding up and slowing down as needed. Variable Frequency Drives today are much more reliable than they have been in the past and their increased use has driven installation costs down. Provident Energy has supplied and installed hundreds of VFDs and we highly recommend their use in a wide range of applications.

For more information regarding VFD applications for your building or to arrange a free energy assessment, please contact the sales department at Provident Energy at 416-736-0630, extension 5.

Tech Corner: Spring Change-Over

For many of us in the Greater Toronto Area, this was the winter that never came. With the recent warm weather during March Break, some clients are considering an early change-over.

Last year, we had several buildings that changed over to Cooling by the third week of April. For Heat Pump buildings, it is important that the Fluid Cooler be ready for the first warm days of the year. We advise getting Fluid Coolers ready by the end of April at the latest.

The vast majority of buildings switched over during the second and third weeks of May. It may be helpful to change over the in-suite cooling, while leaving the Make Up Air units in a Heating Mode until the end of May. This is possible with hydronic (water coil) and packaged air handlers. In this way, if there is a cold snap, there is still a source of heat in the building.

One of the most important things that must be done during the change-over is to check and isolate the basement loop heating systems. In some buildings these systems are fed from Primary Boilers, however, in some buildings these systems are fed from the Dual Systems. When fed from the Dual System, this can result in these loops having chilled water flowing through them resulting in condensation and the ensuing damage to locker contents, drywall ceilings and other areas.

After change-over it is also important to check to make sure that ramp heating and stair melting systems are shut off for the season.

For our clients - it is also important to contact Provident Energy when your change-over is occurring. When switching from a heating to cooling mode, the ‘action’ of valves must be reversed. For example, when in a heating mode, if you need more heat, the valve must open to allow more heat to flow. When a rise in the space temperature (the input signal) needs to result in an increase in an output signal, this is referred to as ‘direct acting’. When a rise in space temperature needs to result in a decrease in the output signal, this is referred to as ‘reverse acting’. An Energy Management System must be told when to work one way or the other.

A carefully planned change-over will ensure comfort through the spring and summer.

Tech Corner: Summer Inspection

Summer is upon us and now is a great time to have your superintendent take a stroll around your building to check on your building systems. Here are some things your superintendent can look for:

-     Cooling Towers – check for water draining out of the main drain on the sump. There should be no excess water draining from the main drain or the float and sump levels might need to be adjusted. Also check for bacterial growth on sump surfaces, the fill, and metal components and even on the rocks around and under the tower.

-     Air Intakes are often overlooked in the winter. Take the time to check any openings in the building for leaves, grass, bird nests or other obstructions. It is also a good time to clean vertical openings such as air plenums for garage exhaust fans.

-     On a warm day, take a few minutes to observe how many windows on the building are open. If there are too many windows open, supply air temperatures and chiller operation may need to be adjusted. Keeping windows closed during cooling operations is a must. Drapes and blinds can also be surveyed.

-     Check the roof envelope integrity. Look for missing rain hoods on stacks and ensure roof drains are clear.

-     If possible, vent pool mechanical rooms. Moist, mildly corrosive air in these rooms can wear out equipment – venting can prolong equipment life.

-     Check lockers and other below grade areas for condensation dripping from water lines and equipment. Ceilings should be checked for water stains.

-     In the summer, pipe tracing, stair melting and other under-slab electric heating systems should be turned off.

Tech Corner: Air Balancing

In virtually all condominiums, fresh air is introduced into the building from the outside through one or more main air handlers, typically located on the roof or in the basement of the building.

The fresh air is air-conditioned at the central source and is then ducted to individual floors terminating at a grille or supply vent located in the hallway.

The typical supply vent will have one or more components. In all cases, the vent will include a directional louver, designed to direct the air down the hallways in a horizontal stream. On the majority of condominiums built within the last 25 years, a set of balancing dampers will be found immediately behind the directional louvers. There may also be a fire damper located behind the balancing dampers, designed to close on a rise in temperature (using gravity or a spring loaded arrangement held in the open position by a fusible link). The fusible link is simply two pieces of metal that are fused together with a metal that has a low melting point. The fire dampers may also be equipped with a damper actuator or motor that is engaged when the fire alarm system sends a signal to the actuators or motors.

Since the air going to individual floors comes from central air handlers, it is necessary to balance the amount of air that is delivered to each floor.

The balancing dampers are equipped with an adjustment screw to control the amount of air delivered to the floor.  Specialized companies provide these air balancing services. Using a measurement device called a velometer, the technician can check the speed of the air coming out of the vent and using a calculation based on the size of the vent can determine the volume of air delivered in litres per second (l/s) or cubic feet per minute (CFM).

Fresh air is used to pressurize the building (to prevent infiltration of outdoor air through the building envelope). It is also used to ‘make up’ for air that is exhausted from the building (bathroom and kitchen exhaust) and to provide fresh air for respiration.

Provident Energy recommends air balancing every two to three years.

~~ Dave Muffitt, Operations Manager