Energy Efficient Hot Water Boiler Plant Design Part 5: Fan Coils, Pumps & Flow Control

So you’ve decided to use condensing boilers on your next project – GREAT! Just remember that this decision will impact other aspects of your mechanical design. Condensing boilers DO NOT operate properly in systems that are designed around traditional non-condensing technology.
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Domestic Hot Water Recirculation Part 8: Proper Application of Pressure Reducing Valves

Pressure reducing valves (PRVs) are a necessary component in just about any domestic hot water system served by a high-pressure domestic water supply main. In this blog we’ll discuss how to apply PRVs properly so that these “necessary components” don’t become necessary evils that create water service problems and huge energy penalties for owners.
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Domestic Hot Water Recirculation Part 7: Balancing Systems with Multiple Risers

Ever have to wait 2 or 3 minutes (or longer) for hot water to arrive at the shower in a hotel room? If you know a little about plumbing design you may assume you’ve had the misfortune of choosing a hotel without a recirculation system. But chances are the hotel does have a recirculation system, it just isn’t properly balanced.
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Domestic Hot Water Recirculation Part 6: Maintaining Temperature Control In Systems with Steam Instantaneous Water Heaters

Applying recirculation to domestic hot water systems with steam type instantaneous water heaters requires a little extra attention. The challenge is temperature control. Under very low load conditions, instantaneous water heater supply temperatures may fluctuate rapidly – even dangerously. Here’s why: During periods of light draw, the heater flow rate may become unstable, fluctuating between a minimal/no load draw recirculation flow rate and that same flow rate plus the draw of a single fixture. That’s what happens when a single hotel guest decides to take a shower at 3AM.
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