Davester
October 29th, 2002, 07:38 PM
Mechanical contractors and engineers, your opinions will be welcomed!
A 50-year-old elementary school near my mother's house is being renovated. Last week, I noticed new package RTUs being installed; it looks like one per classroom (a 2-story building, probably ducting thru corner(s) of upstairs rooms to serve the first floor). The existing system was installed in a previous renovation (mid-1970s), and either replaced or supplemented the original steam radiator heating system. It has a few mid-sized rooftop air handlers (don't know whether they are VAV, multizone, or single-zone with classrooms grouped together) and a Carrier air-cooled chiller (looks to be around 50+ tons and about half the age of the AHUs -- maybe a 10-15 yr-old replacement of the first one?). The building's electrical capacity is also being substantially increased, probably to allow concurrent operation of some 30 RTUs without overload.
My question is: what factors would warrant complete replacement of a chilled water system with RTUs? And, what are some of the "pros" and "cons" of this conversion?
A 50-year-old elementary school near my mother's house is being renovated. Last week, I noticed new package RTUs being installed; it looks like one per classroom (a 2-story building, probably ducting thru corner(s) of upstairs rooms to serve the first floor). The existing system was installed in a previous renovation (mid-1970s), and either replaced or supplemented the original steam radiator heating system. It has a few mid-sized rooftop air handlers (don't know whether they are VAV, multizone, or single-zone with classrooms grouped together) and a Carrier air-cooled chiller (looks to be around 50+ tons and about half the age of the AHUs -- maybe a 10-15 yr-old replacement of the first one?). The building's electrical capacity is also being substantially increased, probably to allow concurrent operation of some 30 RTUs without overload.
My question is: what factors would warrant complete replacement of a chilled water system with RTUs? And, what are some of the "pros" and "cons" of this conversion?