#resistance

Tech Tips:

Suppose you have two extension cords. One is a nice, thick #10 50′ cord with good ends, and the other is a crappy #14 25′ cord. Unfortunately, you need to connect them both to get to your drill 75′ away. Which do you connect to the plug, and which to the drill? Come up with […]

Parallel Circuit Resistance

In a series circuit (loads connected in a row end to end), it's easy to calculate total circuit resistance because you simply add up all the resistances to get the total. In a parallel circuit, the voltage is the same across all the loads; the amperage is simply added up, but the resistance is a […]

What Causes Voltage Drop and How to Deal With It

Voltage drop is one of those topics we often mention but seldom think about in-depth. From a very basic standpoint, we need to know whether or not the rated voltage is being delivered to the device or appliance while under full load, which is as simple as running the equipment and measuring the voltage at […]

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Bryan discusses surge protection devices (SPDs) with Mike from DITEK, focusing on practical applications for HVAC contractors and how to provide value to clients. Mike emphasizes that surge protection is essential for modern HVAC systems, particularly given that they are typically the most expensive appliance in a home and increasingly rely on sophisticated electronic components like variable-speed compressors and inverter boards.

The conversation delves into installation best practices, with a detailed discussion of proper wiring techniques for SPDs. Mike explains that surge protectors should be installed in parallel with the circuit, typically at the disconnect, and addresses common concerns about double-tapping lugs and ground connections. He emphasizes the importance of keeping wire lengths as short as possible and provides guidance for installations both with dedicated disconnects and panel-direct connections.

A significant portion of the episode focuses on DITEK’s Kool Guard (KG2) product, which represents an evolution in HVAC protection by combining surge protection with voltage monitoring. Mike explains how modern HVAC equipment, particularly inverter-driven systems, is increasingly sensitive to both over-voltage and under-voltage conditions. The Kool Guard monitors voltage on each phase independently and provides visual indication of fault conditions through LED indicators, making it easier for homeowners to identify potential issues without opening electrical enclosures.

Key Topics Covered:

· Why every modern HVAC system needs surge protection

· Installation locations and proper wiring techniques for SPDs

· The difference between line-side and load-side installation

· Ground connection best practices

· How to protect both condensers and air handlers

· The evolution from basic surge protection to voltage monitoring

· The importance of voltage monitoring for modern inverter-driven equipment

· How Kool Guard monitors voltage phase-to-ground vs line-to-line

· Common power quality issues beyond lightning strikes

· How to discuss surge protection with customers

· The limitations of utility-provided surge protection

· The impact of aging power infrastructure on power quality

· The advantages of USA-made surge protection products

· How voltage monitoring prevents damage from brownouts and over-voltage conditions

· The pre-programmed voltage protection ranges in Kool Guard

· Visual indication features for fault conditions

Learn more about DITEK at https://www.diteksurgeprotection.com/.

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