#3 wire

Tech Tips:

3-Wire and 4-Wire Condensing Fan Motor Connection

Diagram courtesy of Emerson New techs have a common question of how to wire a condensing fan motor for 3 vs. 4 wires. Jesse Grandbois submitted this tech tip to help make it simple. Thanks, Jesse! This tech tip is a quick one on the difference between wiring universal condenser fan motors and why brown […]

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Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

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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