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Moduline Question

Moduline Question

Moduline Question

(OP)
Is anyone familiar with Carrier's Moduline system?  Is this a constant or variable air volume system?  I've heard it can be either but cannot seem to find any confirmation.

If I understand this correctly, the constant volume systems are equipped with a bypass damper that re-circulates the air into the plenum when the space does not call for cooling.

If the modulines are equipped with a bypass damper, would they work with a supply fan equipped with a VFD?  What would be the ramifications?

Thanks!

RE: Moduline Question

Moduline units are ideal for air conditioning wide rooms and perimeter zones in a building.
Their modular concept meets the requirements of variable air volume systems.
37AF units can be used in any fixed false ceiling, and the central removable diffuser allows easy access to the control equipment.
Moduline plenums and diffusers are thermally and acoustically insulated by thick fibreglass. In 37AF models, control equipment is completely incorporated in the unit.
An external control system is available as an option. 37AF Moduline units are suitable for fixed false ceiling installation (plaster) or where there is limited access close to the units.

RE: Moduline Question

Moduline units normally operate as variable volume systems.  There are two types of AHU which are commonly used to deliver conditioned air to the Moduline units, first is the variable speed supply & extract fans and the second is fixed speed fans with a modulating by-pass damper between the supply and return.  I prefer the variable speed fan system personally.

It is a simple task to convert a Moduline unit into fixed volume device by fitting a fixed volume regulator to each Moduline box.

Let me know if you need any more information.

Tony

Carrier UK

RE: Moduline Question

(OP)
Thanks for the info.  What is required to change a constant volume Moduline into a variable volume moduline?

Are all constant volume modulines equipped with a volume regulator?  Can this be easily removed if the supply fan has a VFD?

RE: Moduline Question

You need to remove the constant volume regulator (located at the end of the Moduline box) and replace it with a variable air volume controler.  If you have a number of Moduline units serving one area, it is possible to operate several slave units from one master unit.

If you post your e-mail adress, I will send you a technical manual that details how to select and install Carrier's Moduline units.

Regards,

Tony.

RE: Moduline Question

You also have to understand the unit mounted thermostat & means of slaving other moduline units. You should only slave units that are on the same duct branch run so pressure to each moduline plenum is approximately equal. Get their sound performance rating & operating pressure range. Make sure you have sufficient pressure in the duct and use the appropriate size for the CFM duty to avoid noise.

RE: Moduline Question

(OP)
The model number of the moduline is 37AJ1148-(10-2).  Any idea if this is a VAV or CV box?  I can't seem to find this model in the literature...

RE: Moduline Question

You can look this information up from Carrier's web page.  I found information about Moduline equipment there.  Good luck with retrofitting Moduline systems.  My experience is that parts are hard to come by. Also, keep in mind that the Moduline system is "system powered" which means the control of the Moduline diffusers requires a very high duct static pressure to operate properly.  From an overall energy efficiency and long-term cost effectiveness, you might want to consider converting the system to a true VAV system with regular terminal units.

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