VRF condenser (outdoor) unit location

[Dibastidas]

Hi friends,

My team and I are developing a study to climatized several areas in a warehouse building in Peru. In one of the areas we are recomending a Carrier VRF unit Outdoor model: 38VR006H113010 (53100 BTU) that will supply 2 High wall units model: 42VH024H113000100 (24200 BTU/EACH. Originally we had in our AFCs the condenser unit located in the exterior of the building, nevertheless the construction team is suggesting putting the unit inside the warehouse, considering that the interior temperature of the building is aroung 31°C in the summer and averages around 22°c year round with the lowest being 19°C. Now, generally speaking is not recommended to place an outdoor unit in an inside area. So as an engneering team we are recommending maintaining the condenser unit in the outdoor of the building unless it is not possible. So it will allow the unit to have an unlimited access to outdoor air which is important for a good air flow and performance, preventing the inside of the building to be affected by the heat exchange process between the indoor and outdoor unit, placing the condenser unit indoors will reduce the system’s air supply, which will limit the amount of heat that is able to remove from the pantry/commissary area. Locating the unit inside required a study of existing exhaust and make-up air system in the warehouse in order to guarantee a proper air flow.
The outdoor temperature averages are:
• Warm Season Average daily high temperature: 81°F (27.22 °C), low temperature: 69°F (20.55°C)
• Cool Season Average high temperature: 66°F (18.88 °C), low temperature: 59°F (15°C)

I'm having a hard time to find the applicable code that mentions that the condenser unit should be outdoors.
Does anyone have the code or any recommendation about this issue?

 

[SAK9]

A small condensing unit such as the one you have can be located indoor if the ware house is either naturally or mechanically ventilated .I have seen condensing units being located in ventilated basement car parks.

 

[GT-EGR]

On this topic I’m pretty sure code doesn’t do anything more than tell you to follow manufacturers installation requirements.

There’s nothing particularly against code about putting it inside, the air doesn’t come out any dirtier, so it doesn’t fit the definition of exhaust. And you already run the refrigerant inside, so that didn’t change either.

Your main issue is that you’ve just added another source of heat to the space that needs to be cooled, not much different than a windows solar gain. So as long as whatever cooling method you have in place can handle this additional load, it shouldn’t be an issue. Just remember that your VRF system is now directly relying on your main AC system, so now you have two potential failure points.

An inspector may question it, but you just have to be ready to justify your design. But if you didn’t have a good reason to put it inside (refrigerant runs too long, no space available) then you should just put it outside.

Putting a small condense in a large warehouse or large garage space is usually not noticeable, it’s when you put them in a small room or above a ceiling that you end up with a big problem.

 

[willard3]

I have had to solve the problem of rejecting heat in confined spaces inside the building many times over the years and you're just adding heat to a space. It's bad Engineering.

 

[Drazen]

no code will teach you very basics of engineering.