A fan coil is hard-connected and vibrating the ceiling grid
A fan coil or fan-connected unit hard-piped to duct can transmit motor vibration. Add the approved flexible connector/isolation detail and make sure the duct is independently supported.
This fan coil/unit is hard-connected to duct and vibrating the grid. I checked supports and the submittal detail. Do you want a flexible connector/isolation break installed at the discharge/return connection?
Watch out
Do not use the rigid duct connection as the vibration isolator.
Check
Confirm the vibration source is the unit, not loose ceiling, hangers, or duct rubbing.
Check whether a flexible connector/isolation detail is shown on the submittal/drawings.
Make sure ductwork is independently supported and not hanging from the unit collar.
Check connector material, slack, alignment, and access.
Recheck vibration/noise after startup.
Steps
Confirm the vibration source is the unit, not loose ceiling, hangers, or duct rubbing.
Check whether a flexible connector/isolation detail is shown on the submittal/drawings.
Make sure ductwork is independently supported and not hanging from the unit collar.
Check connector material, slack, alignment, and access.
Recheck vibration/noise after startup.
Say this to your foreman
This fan coil/unit is hard-connected to duct and vibrating the grid. I checked supports and the submittal detail. Do you want a flexible connector/isolation break installed at the discharge/return connection?