Residential units used for commercial use?
We are upgrading the hvac at a church and we got a proposal from one contractor that includes four 5-ton units to be used for the main sanctuary. specifically these are space-pak units. also there would be two water boilers for heating with heating coils in the space-pak units.
The existing system is steam with radiators throughout the church.
The new system proposed for the rest of the church would be to install smaller split units and furnaces.
I don't expect you to understand the whole job but my concern is using multiple smaller residential type units instead of a larger commercial unit to do the job.
any comments appreciated
5 ton or less split systems are inexpensive and will give you redundancy. You can have a unit down w/o being totally w/o heat or cooling. Because this is a commercial application the units should be equiped w low ambient temp packages and crankcase heaters.
Redundancy, lower installed cost, availability of parts, tech competancy doesn't have to be particularly high, ease of control / zoning. Higher efficiency equipment more readily available
More parts to break. Units may have to be retrofitted w equipment to allow operation at low ambient temps, fresh air requirements may be harder to meet and or control.
Anyone can service also.
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Good system but sell them on outside air economizers
With a church there will be many times that outside air will do the cooling job and it's always there for fresh air requirements too.
The conventional view serves to protect us from the painful job of thinking.
When you say "smaller, residential type units," you mean split systems, yes? I don't see RTU's in residential service (I suppose they crop up in mansions, etc) and an RTU is where you would find an economizer.
Originally Posted by trolls
Depending on the size of the church, a chiller and boiler with air handlers and fresh air ducts might be best. Smaller churches often have split systems (mine does) with a few RTU's over hallways and other areas with flat roofs.
Split systems are widely used in retail stores in malls where there is no common heating and cooling plant, and where two levels of mall make RTU ducts to the lower level too difficult or expensive. There is not much difference between a residential split and a small commercial split. you can add heat pumps with air handlers that have electric backups.
So, for the rest of the church, split heat pumps might be the way to go, as long as you have a way to get fresh air into the space.
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i like the chiller idea just because churches get hit more than any other place by copper thieves and thats just all the more that can get stolen