InspectionNews - Home Inspection - Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection

InspectionNews - Home Inspection - Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection http://www.inspectionnews.net/home_inspection en Fri, 20 Nov 2009 19:43:06 GMT vBulletin 1440 http://www.inspectionnews.net/home_inspection/images/ca_evo/misc/rss.jpg InspectionNews - Home Inspection - Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection http://www.inspectionnews.net/home_inspection flex ducts in concealed space? http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16611-flex-ducts-concealed-space.html Fri, 20 Nov 2009 06:52:53 GMT I'm getting conflicting info on this one. Are flexible ducts allowed to be installed in a concealed space - like in a floor joist bay that runs between two finished levels in a house?

I had never really thought about it since I don't see a lot of concealed spaces as I inspect houses but I'm running ductwork for an addition I'm putting on and can't get a straight answer.

Duct supplier says no they have to be sheetmetal (big surprise, he sells sheet metal and fabricates ducts). A couple calls to local HVAC contractors left me more confused then when I started. Just lots of 'maybe'

An inspector friend in a neighboring county to where I live said no problem as long as they're not penetrating a fire separation wall.... of course.

Anyhow, the attached pictures are of the metal ducting at the end of the existing house which I plan to tap into and extend to the new rooms (pictured at framing stage). Flex ducts would be much easier.... I'm calling my AHJ in the morning. I'm just curious what you guys think.

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]]> Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection Matt Fellman http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16611-flex-ducts-concealed-space.html Vent near window http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16608-vent-near-window.html Fri, 20 Nov 2009 03:29:05 GMT I wrote this in the report, vent too close to window. Pretty simple, right? Well the HVAC contractor called me and said the vent can be located 3 feet from the window if the furnace is 100,000 btu's or less. I have not heard of this. Plus is was 33 inches, that pissed him off. Have you heard of this rule. I simply refered to 1804.2.6 IRC

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]]> Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection mathew stouffer http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16608-vent-near-window.html Would you write this up ? See photo http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16536-would-you-write-up-see-photo.html Tue, 17 Nov 2009 02:44:46 GMT Condenser disconnect in sight of unit, but behind fence (and no gate). You can just see the top of the disconnect on the other side of the fence. Condenser disconnect in sight of unit, but behind fence (and no gate). You can just see the top of the disconnect on the other side of the fence.

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]]> Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection Gene South http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16536-would-you-write-up-see-photo.html Age of Temco wall furnace http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16510-age-temco-wall-furnace.html Sun, 15 Nov 2009 16:16:15 GMT Does anyone know the year of Temco wall furnace model #1071?:confused: Does anyone know the year of Temco wall furnace model #1071?:confused: ]]> Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection Nick Iellamo http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16510-age-temco-wall-furnace.html HRV - Failure To Understand The Concept http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16507-hrv-failure-understand-concept.html Sun, 15 Nov 2009 09:19:37 GMT As I noted in another thread or two, I recently inspected a building that was once a Welcome Center for a developer and was later donated to a church and moved to its present location. (The property also included a Quanset hut.)

Due to the large number of occupants during church services additional fresh air was required to maintain indoor air quality in this building. An HRV (Heat Recovery Ventilator) was installed to supply this fresh air.

For those that are not familiar with HRVs (and the close cousin the ERV - Energy Recovery Ventilator), an HRV is essentially a heat exchanger that recovers heat that otherwise would be lost in the ventilation process. HRVs are usually 60% to 80% efficient. The air flow in equals the air flow out so the building is not pressurized or depressurized by the HRV.

In a heating environment (such as Colorado) 60% to 80% of the heat in the inside air that is exhausted is picked up by the cooler outside air being brought into the building. The outside temperature here today was 30 degrees. With the indoor air at 70 degrees, after passing through the HRV the 30 degree outside air would be heated to somewhere around 55 or 60 degrees. The higher temperature of the fresh air will reduce the operating time of the furnace and reduce the utility bill.

I do not typically inspect HRVs during a home inspection but I noticed something odd about the one in the church. The two registers in the room were fairly close together and I thought they might short circuit so I turned on the HRV to find out. One register should have been a supply and the other should have been an exhaust. I was surprised to find that both registers were blowing 30 degree air into the room. When I checked the two outside grilles they were both drawing air in.

So, the HVAC contractor installed the HRV incorrectly. With both intakes located outside there is no exchange of heat. The HRV has now become a giant intake fan that delivers twice the intended CFM, pressurizes the building and causes a tremendous loss of energy while making the building very uncomfortable.

The preacher said the HRV moved too much air and made the room cold in the winter. Now I think I understand why he said he didn't like to run the HRV.

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]]> Heating, Ventilation, Air Conditioning (HVAC): Home Inspection and Commercial Inspection Bruce Breedlove http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/16507-hrv-failure-understand-concept.html