Inspecting Commercial HVAC Systems Course Student Forum

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This image, of a natural gas boiler, was taken in the utility room of a small commercial office space. The boiler supplied heat to an infloor radiant heat system. This heating system was not combined with any visible method of “air exchange”. Poor or inadequate air exchange in a building can lead to issues with air quality. A condition known as “Sick Building Syndrome” can be the result of inadequate air exchange. The following comments were included in the written report:
No visible method of “air exchange” noted. The heating system in this building would be described as an infloor hydronic heating system. Hot fluid is supplied (from a boiler) and circulates through a coil system within the floors of the property. When heat is called for at the thermostat, the boiler responds & distributes the heated fluid through the infloor coil system. A modern infloor heating installation requires a method of exchanging the air within the building. Regular air exchanges are needed to maintain suitable indoor air quality. Without regular exchange of air, moisture and indoor air pollutants can accumulate in the building - negatives for both the property and the occupants. With this type of system, air exchange and ventilation is often handled with a HRV unit (heat recovery ventilator). A HRV unit did not appear to be present in this installation. A method of air exchange may or may not have been required when this system was installed, however for peace of mind, I do recommend that a licensed HVAC technician be consulted for options to correct.

I chosen to write about the article on Smoke Detectors.

From 2003 - 2006 nearly two-thirds of fire related deaths occurred in homes where smoke detectors were either absent or non-functional. Smoke detectors may be either hard-wired or battery operated. A smoke detector should be installed in the following locations: on each level of the home, in each bedroom, the basement and the garage. To ensure function, smoke detectors need to be regularly tested. With battery operated units, it is recommended that the batteries be replaced twice yearly. Detectors do have a limited useful lifespan. Replacement is recommended every 7-10 years or at any point where the detector sustains damage or proves to be non functional when tested.

I’ve chosen to write about the article on “Ghosting”.

Ghosting is a term that refers to discolouration that can appear on the walls and ceiling surfaces of a home. Ghosting occurs when airborne “particulates” are present. When the particulate laden air contacts these interior surfaces, the particulates tend to stick - eventually attracting a dust/dirt layer that is visible on the surface. Airborne particulates can be the result of cooking fatty foods, fireplace use, candle use and pet dander. Ghosting is often be most visible on perimeter walls and directly above heat registers, fireplaces and doorways.

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This air conditioning condenser coil unit located outside of a 110 sq. mtr. restaurant dining room was manufactured by Nordyne Industries for Westinghouse in the month of April 2004. The unit is sized at 2 tons which can efficiently cool an area of up to 130 sq. mtr. in this climate area indicating that this unit is properly sized for this space. The SEER rating on this unit is 10. While this may have been an excellent rating 12 years ago it is below the industry standard of 13 in today’s world. SEER is a measurement of seasonal efficiency. Units of this type today can be rated as high as 25 SEER. This A/C unit has an expected lifespan of approximately 15 to 20 years in this geographical area.
Visually this appliance appears to be in good condition, however, could not be tested as the outdoor air temperature was only 5 degrees C. In this regard we recommend that the purchaser obtain a declaration of performance from the vendor on closing.

This is an image of an eyebrow hood, which was manufactured by Hobart. This eyebrow hood is in front of bakery oven in a commercial setting. When the oven door is opened, steam escapes, and gets captured by the eyebrow hood. This steam is then released through the exhaust vent at the roof of the building.

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Condensing coil . On a window A/C unit . Unit seem to be in normal condition filter needs cleaning , this is done by simply running through clean water. This unit happens to be a Frigaire model 3speeds with a auto & econ mode setting . Also a cut -off timer . A/C only &fan

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In this assignment on inspection in the Commercial HVAC course, I selected this picture of two roof top RTU’s that I inspected. These units are brand new on a brand new building that wasn’t yet occupied but passed all permitted inspections. The units were located close together in a T figuration. However, the defect here is the intake on the closer of the two units. The intake was measured at 18” from the side of the second unit to the intake opening on the first unit instead of 36” as noted in installation manual. I noted on the report its potential to restrict incoming air volume to the first unit and restrict it’s output into the building.

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In this part of the reading and writing assignment, I chose “Bag house Inspection.” In this article, they describe a bag house as a sealed container filled with bags that traps contamination in the air exhaust filtering system used in commercial and industrial buildings. Most bag houses are used on the exhaust air to filter pollution and dust produced by equipment or processes in the building. These houses may use several different ways to extract the dust from the bags into a hopper below for collection and removal. Overall, bag houses are used to clean out going exhaust air from the building’s pollution and dust producing processes.

In the second article, I selected “Dust Inspection.” In this article they describe how dust produced by the business process has many different affects on the employees and environment. Lager dust particle can be more of inconvenience but the smaller particles may cause respiratory issues. Cotton dust may contain harmful organisms while other dusts from wood or chemicals may be explosive in certain quantities. With proper installation procedures and air filtering units, dusts can be reduced or eliminated. It’s also important to reduce the incoming dusts from carriers such as people, equipment or building infiltration. The proper procedures when working around dust producing processes is important in the protection of explosions or health issues.

This is a split system residential air conditioning unit. The outside unit is a Carrier brand. The serial number shows it was manufactured in 1996. The model number on the unit indicates it is a 24,000 BTU/hr size or 2 tons. The air conditioner appeared to work properly using the normal controls.

This Whirlpool Portable Dehumidifier is being used in the laundry room in this home. The laundry room is the greatest source of moisture introduced into this home. There are many children. The wet towels from nightly showers are enough to cause issues with heightened humidity. This particular unit has done a very good job at mitigating any moisture issues. The unit is about 10 years old and is in very good condition. Prior to utilizing the dehumidifier, there were occasional small patches of mold that appeared when items were stored on top of the cabinets and placed too close to the ceiling. Controls on the unit include three fan modes of low, high, and auto. There are four modes of normal, dry, max dry, and continuous run to regulate the level of dehumidification. There is a power button and an automatic shut down feature for when the reservoir tank is full of water and needs to be emptied.

So this relates to a Commercial HVAC System HOW???

Although this is a residential unit the same thing can happen to commercial units. The compressor and condenser line were frozen due to dirty coils causing inadequate airflow. This is why it is important to change air filters every 30 - 90 days depending on the type of filter, along with regular maintenance. What isn’t shown here is that the condenser line was running in the attic (line was frozen). Hot attic plus ice melting will cause water damage to the surrounding materials. Happy Inspecting everyone.

I read the article about window films.

Window films when used properly will not only aid in reducing the amount of UV light entering a building but it will also help reduce the heat load placed on the HVAC system. a small investment in applying a solar film on your windows will create a decent ROI through a reduction in cost of use on running your HVAC system. If done properly you may be able to recoup the money spent on the window treatments through the savings on the HVAC.

Here is a high efficiency boiler in a an animal sanctuary. The boiler has an indirect water heater and radiant floor heat. The unit functioned properly. boiler.jpg

I read the article titled “creating a team of expert consultants for your commercial property inspection business”. I found the idea interesting of hiring an entire team of contractors to tag along on commercial inspections. I was recently asked to do a commercial inspection for a large restaurant, bar, motel. The cost of all these subs would most likely exceed the budget, being that the asking price was less than a typical house in the area.

Ed Tennyson signing in

Good night everyone

DSCN1168.jpg This is a picture of a RTU or Roof Top Unit. This RTU is a 1998 Goodman a/c unit this RTU had some issues with the cast iron pipe that supplied the natural gas to the unit. The cast iron pipe was rusted and needed to be replaced by a qualified HVAC tech. Other than the rusted supply line the RTU was in good working condition.

I have read the article involving “chimneys: preventing a collapse”. A chimney collapse can cause structural damage to the building and its surroundings and most importantly the falling brick or stone could potentially be fatal to people on the ground. Inspection and maintenance of the chimney are critical safeguards against a chimney collapse.In actively seismic regions the chimney the heaviest and most structurally vulnerable of all exterior components of a building should be inspected regularly.
Chimneys should be inspected for the following defects, Loose or missing mortar between the brick or stone, Missing or insufficient lateral support and mechanical damage to the chimney such as that caused by falling tree limbs or scaffolding. The footing of the chimney is very important to the structural integrity of the chimney loose or poor soil below the footing, undersized footing and deterioration of the footing itself can be a cause for a chimney collapse so all those aspects should be inspected.

Roof Top Units located on top of a commercial building. They are easily accessible. They are used to cool the commercial building. They are air cooled units.

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