Condensate Drain Codes & Best Practices
It should be stated and restated that codes and code enforcement vary from location to location within the US. The IMC (International Mechanical Code) is one of the most widely utilized and referenced. The 2015 version of the IMC section 307 is what I will be referring to in this article. Condensate Disposal  The code […]
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Condensate Drainage in a High Efficiency Gas Furnace
This article was written by HVAC/Furnace technician Benoît Mongeau. Thank you, Ben.     High efficiency (or 90%, or condensing) furnaces use a set of two heat exchangers in order to retrieve more heat from the combustion products than their mid-efficiency counterparts. Because of this, they generate flue gases much colder than those of a […]
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Condensate Switch Controversy
Condensate overflow prevention devices or float switches, as they are often called, are such simple devices that you wouldn't think there would be much room for controversy. In my experience, there are few areas of the trade where technician and installer preferences and opinions vary greatly. Let's start with some float switch basics. Float (condensate) […]
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Stacking Evaporator Coil Stages
In commercial HVAC, you will find several different types of multi-stage evaporator coils: intertwined (shown above), horizontal face split (one coil on top of another), and vertical (side by side). When staging a horizontal evaporator, pay attention to ensure that stage #1 is on the bottom and stage #2 is on the top. If stage […]
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Condensate Pump Drains
One of my techs (Jim Walch) brought another common “double trap”-style issue to my attention: techs and installers running a drain too far into a condensate pump. When you run the system drain too deep into the pump reservoir, the water level can rise high enough to cover the drain end. That can create the […]
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Drains and Double traps
Double traps are no good. That's the end of this tech tip. Okay, here's some detail: Anytime your drain goes up and down more than once, you have a double trap UNLESS you place an air vent between the two traps that vents ABOVE the drain inlet. The double trap causes drainage issues because air […]
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