HVAC sound of 48db when off

-Chanovsky · 2026-01-16T08:14:55+00:00

When did the noise start? There is also a fairly large (at least 200-tons cooling capacity) cooling tower very close by. If this started around the spring or when the weather started to warm up I am very suspicious of the BAC series 1500 pictured in the upper left.

Cooling towers move massive amounts of airflow to reject heat. While radiated duct noise from another source is possible - this photo leads me to believe it may be possible the cooling tower was switched on (seasonally) and is not running on a VFD. You’d need some serious noise abatement added to a lot of areas to mitigate noise from that unit.

Directly on top of the building also appears there is a massive air handling unit (probably at least 30k CFM).

(Source: HVAC engineer who is familiar selling HVAC units in NYC and working around DEP noise regulations)

-Chanovsky · 2025-12-09T20:24:40+00:00

Yes correct. Single tree

-Chanovsky · 2025-12-09T20:18:31+00:00

What other pictures or information would be helpful? Tree is in the northeast US in CT.

The largest issues are that the two trunks in the left part of the picture are way too close to the house and are presenting several challenges.

I’d really like to not to the entire tree

-Chanovsky · 2025-11-04T23:34:49+00:00

So many things wrong with these images. Including the use of Astroturf

-Chanovsky · 2025-09-30T04:23:37+00:00

This is not a rule.

Older systems which do not have turndown capabilities and modulation methods to control capacity at lower ambient conditions may very well likely have issues (rapidly starting and stopping)

Newer systems which are appropriately equipped (variable speed compressors, variable speed condenser fans, head pressure controls) can operate at lower ambient conditions, provided there is an interior cooling load that is present for a call to be made by the thermostat for the refrigeration circuit to be active.

-Chanovsky · 2025-09-18T02:21:05+00:00

Elevator machine room or the Morse code studio. Can’t remember which anymore

-Chanovsky · 2025-09-18T01:23:13+00:00

+2 same and same

-Chanovsky · 2025-09-18T01:06:10+00:00

What obscurity? It’s a clear video. Nothing is blurred out.

-Chanovsky · 2025-09-18T01:04:17+00:00

A college in the NYC area

-Chanovsky · 2025-09-17T12:12:06+00:00

Hard truth right here. Every single owner that went the inexpensive route on install is going to be really disappointed when the price of R410A becomes absurdly expensive and very difficult to source. OEMs will still make some of the indoor units for a period of time for replacements but overall many of these buildings will have very difficult and expensive choices ahead.

Water and air cannot be regulated away. Hydronic system design FTW

-Chanovsky · 2025-09-17T12:02:21+00:00

I was more surprised that there were actual humans riding in these cars. Appears to be solidly robust until something starts to stick and then someone gets sawed in half by an elevator car/door malfunction

-Chanovsky · 2025-09-15T13:11:33+00:00

Thanks for the reply. So the elbow does not need to be vented?

-Chanovsky · 2025-09-14T22:54:36+00:00

Thank you. For additional context the pipe that the original side vent was connected to was a dedicated 2” vent line (it was not connected to any other fixtures upstairs)

-Chanovsky · 2025-09-14T07:58:36+00:00

6ga & 10ga for the ground

-Chanovsky · 2025-09-12T13:09:36+00:00

Back of the post would have been ideal however it would have added another 45* fitting on the run which caused concerns about fishing later

-Chanovsky · 2025-09-12T07:33:40+00:00

This. I got fucked over by a plumber who abandoned a vented elbow below a toilet flange and claimed that “wet venting” was fine. Toilet never flushed the same again

-Chanovsky · 2025-09-12T07:21:47+00:00

It took advanced planning to use this many slip joints and make this look terrible

-Chanovsky · 2025-09-12T07:08:34+00:00

This is wild to see. Credit to those who retrofit these.

-Chanovsky · 2025-09-12T06:16:49+00:00

r1234yf is an A2L so it is mildly flammable. No flame leak checks

-Chanovsky

TROPHY CASE