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Nathan Rothenberg
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Tech Tips written:

Shielded Control Cable & Communicating Controls
When I first started in the trade, we used to run into shielded control wires on the Carrier Comfort Zone 1 zoning systems and also on a Carrier VVT system I used to maintain at a bank. I knew it had something to do with electrical “noise” and that communicating systems often called for it, […]
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AHRI Ratings Are Not Design Conditions
I’ve been designing a system for a home here in Dallas and noticed a couple of interesting (and disturbing!) things about the equipment’s advertised capacity vs. the actual capacity at design conditions.  Equipment is rated at AHRI conditions (95 degrees outside and 80-degree dry bulb, 67-degree wet bulb inside). These conditions make equipment performance LOOK […]
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Valve Core Removal Tools
Valve core removal tools were originally developed to remove damaged valve cores without the need to pump the system down. This technology was a major leap forward in work efficiency, as pumping down a system can be a tedious and time-consuming task.   Eventually, technicians discovered that removing valve cores led to faster evacuation, recovery, and […]
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Podcast guest:

Manual J Battle with Ed and Nathan
Nathan Rothenberg and Ed Janowiak join Bryan to talk about the good, the bad, and the uncomfortable of ACCA Manual J, D, and S. Manual J load calculations exist to make the BTU inputs and outputs predictable. Then, Manual S comes in to assist with equipment selection to meet the load calculations and the customer's […]
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