Last week’s forum activity was rich with practical advice and intriguing discussions. Members exchanged thoughts on the challenges new technicians face with complex systems, and debated the origins of certain industry superstitions. There was also lively conversation about the most effective scheduling tools for crews, along with technical discussions on airflow measurements. Finally, the community weighed in on whether closing vents is a legitimate energy-saving tactic or just a myth.
This Week’s Hot Topics
Where new techs stumble on big systems
The learning curve for new technicians tackling large HVAC systems is steep. This discussion digs into specific challenges they face and how seasoned pros can lend a hand.
Origin of the Friday startup superstition
Ever wondered why some techs avoid starting a system on a Friday? This thread explores the roots and validity of this common superstition.
Crew scheduling tools that actually work
Finding the right scheduling tool can transform workflow efficiency. Members share their experiences with different platforms that have proven effective.
ESP-to-CFM quick check for MERV 13
A technical discussion on ensuring proper airflow when using MERV 13 filters. This is crucial for maintaining system efficiency and air quality.
Closing vents: energy saver or myth
Does closing vents really save energy, or could it do more harm than good? This debate delves into the pros and cons to uncover the truth.
I only green‑light a Friday startup if we set BMS/data‑logger trending (supply temp, ESP, compressor amps) and book a quick Saturday check; otherwise I push to Wed/Thu so we can babysit the first 24 hours. Friday startups are like launching a boat at dusk — you won’t see the leaks until you’re out a ways — @TinaHVAC do you keep a ‘day‑zero’ log with gauge photos so Monday’s tech knows what normal looked like?
Midweek only unless the owner pre‑authorizes weekend support from controls/balancing — vendors vanish after 3pm Friday and you eat the callback. If it’s forced, @Guide, I do a 2‑hour “burn‑in” Thursday, verify airflow/ESP, set conservative static/low‑temp safeties with auto‑email alerts, and delay the warranty start to Monday.
I do a 30‑minute “soft start” at about 60% fan with the economizer forced closed and only stage 1 enabled before any Friday startup; it exposes condensate and control hunting without overcommitting the plant. @alex_99baker, do you cap stages for weekend runs?
I block a ‘stabilization window’ in whatever ‘scheduling tools’ you’re using for the first business morning and set 1‑minute BAS trends on supply air temp, duct static, and valve/damper positions — , catching overnight hunting early has saved me more than once. If you’re forced into a late‑week go‑live, at least disable deep night setback for the first night so humidity swings don’t trip safeties.
If I’m stuck with a Friday startup, I crack the high-point vents and run the CHW/HHW pumps in HOA for 15–20 minutes at noon to purge air, then trim the pump dP setpoint about 10% for the weekend to avoid nuisance flow trips. > late‑week go‑live, at least disable deep night setback for the first night so humidity swings don’t — agreed, and pairing that with a midday hydronic purge has saved me more Saturday callouts; @blee908 do you also pop the auto-vents to confirm flow?
One thing I do is disable ‘optimal start/stop’ and widen the SAT and duct static deadbands one step for the first 24 hours after a Friday startup; it keeps the BAS from ‘chasing its tail’ all weekend and saves you from Sunday phone calls. Do you also leave DCV off until Monday, or is that overkill?
I set a temporary ramp on the supply-air temp setpoint — no more than 2°F every 15 minutes — so the loops settle smoothly; if the envelope’s leaky I cap the OA damper at about 20% for the first hour, like easing onto the freeway, not flooring it… @jane_doe47 have you tried a ramp like that, and what rate worked for you?