Make up air units or MUA as they are commonly referred to play a vital role in your condominium. The building MUA unit is generally located at the top of the building, either in the mechanical room or out on the roof. The function of the MUA unit is in the an initialism; make upward air to the edifice that gets wearied from kitchen, bathroom and or dryer exhaust systems. The edifice ventilation and the MUA system need to piece of work together to ensure the building pressure is maintained. As well much MUA in a building and noise becomes a common complaint; as well picayune MUA and complaints of smells in the hallways are more than prevalent. The MUA needs to ensure the hallways are pressurized which helps proceed cooking odors etc. localized to each suite.

Air Balancing

One detail that is often overlooked with MUA systems is the air balancing portion. Over the years information technology's not uncommon to have tenants make adjustments to the hallway diffusers that accept an adverse effect on the overall system. The system should be checked and rebalanced every and then often to ensure each floor is receiving the proper amount of air. The airflow is measured in Cubic feet per Infinitesimal (CFM) The full CFM of the MUA system is recorded and compared to the nameplate rating. The balancing and adjusting of every hallway grill on each floor is carried out and recorded to ensure the proper airflow is being delivered.

Hallway Temperatures

The bulk of MUA systems atmosphere the air in the wintertime to ensure icy cold air is not being delivered to the hallways. Some MUA systems are designed to provide cooling in the summertime as well. One complaint I hear all the fourth dimension is that the hallways temperature doesn't feel the same equally my unit. Hallways practice not need to be kept at 23C (74F) in the winter time, 20C (68F) is more an adequate temperature; the hallways are not living spaces. It is important to remember that the amount of gas required to heat upward the exterior air from -10C to a comfortable hallway temperature is very meaning. The difference betwixt a house furnace and a MUA is that the MUA is always trying to rut exterior air, -10C in this case,  compared to a home furnace heating up the return air coming back  around 20C.

Regular Preventative Maintenance

I can't stress enough the importance of regular preventative maintenance. The MUA filters in many cases may require changing every month, if y'all merely have Bi-monthly inspections then every ii months is adequate. The MUA belts, motor and components need to be inspected likewise. I observe the inlet dampers on a lot of MUA units get neglected and should be lubricated twice a yr. Every bit with whatsoever gas-fired appliance a major inspection should be carried out on an annual basis where the major components such as the burners, ventor motor, estrus exchanger etc. are thoroughly inspected. This service should be scheduled for the summer.

Variable Frequency Drives

You take probably heard the term Variable frequency drives (VFD) a lot in the last 10 years. These are devises that are installed on pieces of equipment to irksome the performance of a motor or pump. With respects to MUA units a VFD drive can pay for itself in just a few years. The function of the VFD on a MUA unit of measurement is to slow down the motor and deliver less air. The VFD is typically set up on a timer to provide a percentage of the total CFM the building requires. There are certain times of the day that crave less brand upwardly air. The peak demands for air will be first thing in the forenoon when residents are getting ready for work and after work when residents get home. Laundry machines with dryers, showering, cooking for the nigh office take place at these times of day. During the solar day and overnight when residents are either at piece of work or sleeping in that location is typically not a lot of exhausting appliances operating. When the air flow is reduced during this non-superlative operating hours there are significant gas savings. When the MUA unit delivers less air information technology means in that location is less air that needs to be heated and when the outdoor air is at -10C a tremendous amount of gas is consumed to reach our set point temperature. Equally with whatever type of energy savings there is a fine line that needs to be walked. There are limits to the amount of air that can be reduced with respects to the overall building requirements and the MUA design specifications, I always recommend consulting a professional person to ensure these items are satisfied.

Hither is an case and video tour of a direct fired make upwards air

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Article By Derek Kernick

Bio: Responsible for the leadership and direction of the operations and field service technicians. Ensure the acquirement and turn a profit objectives are accomplished. Coach and develop employees in the role and the field to maximize their functioning, provide feedback and or cosmetic action. Develop plans and marshal work to see contractual obligations and ensure service work is completed in the time allotted. Interview and hire new employees and ensure on-going training is provided. Provide technical support to field staff. Run across with engineers on site to review mechanical retrofits and help provide solutions. See with property managers and board members to review contracts and manage large projects.

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