Sep 26, 2019
When homeowners receive quotes from HVAC contractors, they typically are given two duct replacement options, sheet metal or fiberglass duct board. There is a third option, phenolic duct, that is made of plastic foam with a foil liner on the inside and exterior. It hasn’t been on the market long enough to weigh in on its merits and shortcomings and will not be included in this comparison. Homeowners usually go for the product their HVAC contractor recommends; however, all systems have their strengths and weaknesses. Here are the advantages and disadvantages of two of these materials when installed in the typical residence.
Sep 26, 2019
Prior to 2017, only two items were prohibited for use as grounding electrodes, underground gas piping and aluminum. For 2017, another item has been added to the list of prohibited items. For the 2017 code cycle, the structures as well as steel reinforcement materials that pertain to swimming pools have been added to the list found in 250.52(B)(3) of components that are prohibited from being used as grounding electrodes for an electrical system.
Sep 25, 2019
Anyone who has been on top of a roof on a hot summer day knows what it’s like to stand in the middle of an oven. Extreme temperatures from the sun can bake everything in sight, from shingles to appliances, and even electrical conductors and conduit. Conductor insulation is meant to provide long lasting protection from expected heat due to the flow of electricity and normal environmental factors. However, excessive heat from solar radiation can damage conductors and cause premature failures.
Aug 29, 2019
The Refrigeration, Heating, Ventilating, and Air Conditioning industries (HVACR) are still growing even though they have been in existence for about 150 years. Hundreds of refrigeration uses including fresh food preservation, air-conditioning, and cryogenics should propel the industry well into the next millennium. That kind of growth sounds like a man power issue doesn’t it? So, lets discuss what it takes to be a HVACR technician.
Aug 29, 2019
Two new terms found in Article 100, and a clarified evaluation-practice established for the 2017 NEC cycle. Electrical equipment is generally approved by a testing laboratory before being shipped by a manufacturer. However, sometimes electricians may need to install spe-cialized gear that has not yet been formally certified. When field certification is neces-sary due to a lack of a UL (or other approved laboratory) Listing, electricians are then required to contact a Field Evaluation Body (FEB) to receive an approval label. Fortunately, updates and new terms in the 2017 NFPA 70 National Electrical Code (NEC) help clarify what should be done when items need to be field labeled by a Field Evaluation Body (FEB).
Aug 29, 2019
The method for measuring the countertop space for peninsulas has been changed for 2017. We know that NEC Section 210.52 requires that at least one receptacle be provided for each island or peninsula countertop that fits the dimensional requirements. The intent of the Code here is to discourage the use of extension cords. For example, countertop outlets must be spaced so that the typical two-foot extension cord can reach an outlet from any part of the countertop. Previously, the minimum distance triggering the outlet requirement was measured from the junction where the peninsula abutted the front edge of the perpendicular countertop, thus usually requiring an outlet mounted in the peninsular base cabinet. The new method of measurement begins at the wall behind the countertop.
Aug 07, 2019
It’s mid-January and 15 degrees outside. A fresh snow has fallen and covered all the roads and yards in your neighborhood. Thanks to your natural gas furnace, your home is a toasty 70 degrees. This is because a properly installed gas furnace has a large temperature rise that heats your home quickly and works very well on high demand days. Could it be possible that a new gas furnace will be unavailable as a home heating appliance in the coming decades? Not only is it possible, it is probable.
Aug 07, 2019
Electricity operates within predictable boundaries. We have come to identify these boundaries as Ohm’s Law. Ohm’s Law was developed as a means of explaining how electricity operates within a closed circuit. The Ohm’s Law formula helps to communicate the relationship between different properties within an electrical circuit. We can use Ohm’s Law to explain what has occurred, as well as what will occur, when certain conditions are imposed upon an electrical circuit.
