[Bldg-sim] Energy efficieny: VRF + DOAS vs VRF + unconditioned Ventilation system

[Jim Dirkes]

Santiago,
Another benefit is that the VRF fan is delivering air against a very small
pressure drop - it has no duct to speak of and is commonly multi or
variable speed.  It also often uses a higher efficiency ECM motor

An air handler probably has 5-10 times the pressure drop with standard AC
motor.

On Tue, Jul 21, 2015 at 11:06 AM, Santiago Velez <santiagogvelez at gmail.com>
wrote:

> Thanks Andrew, I wonder though if besides first cost or maintenance
> related issues there are any energy savings at all, and if so why is that
> the case. I Read about better performance of evaporator running with lower
> air temperature in a DOAS, but you still need energy to treat ventilation
> air in the DOAS system, so were are the savings coming from?
>
>
>
> On 21 July 2015 at 10:39, Andrew Corney <andrew.corney at sefaira.com> wrote:
>
>> Hi Santiago,
>>
>> One benefit might be the ability to do the dehumidification remotely via
>> the DOAS system. This could alleviate the maintenance of drip trays /
>> condensate drains from your VRF fan coil units. You might also be able to
>> down-spec the VRF fan coils that you are using as well (possibly reducing
>> size).
>>
>> Another benefit would be that it might be cheaper to do a higher
>> performance style of heat recovery centrally that could help reduce heating
>> energy in particular.
>>
>> So there are 2 reasons!
>>
>> cheers,
>>
>> Andrew
>>
>> On Tue, Jul 21, 2015 at 2:33 PM, Santiago Velez <santiagogvelez at gmail.com
>> > wrote:
>>
>>> Dear Group, Can someone enlighten me about the energy efficiency
>>> benefits of conditioning the ventilation air in a VRF + DOAS system, versus
>>> letting the VRF handle all the load (internal loads + Ventilation loads).
>>> Thanks in advance.
>>> Regards,
>>> Santiago.
>>>
>>> _______________________________________________
>>> Bldg-sim mailing list
>>> http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
>>> To unsubscribe from this mailing list send  a blank message to
>>> BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG
>>>
>>>
>>
>>
>> --
>> Andrew Corney
>> PE M.CIBSE M.ASHRAE
>> Product Manager - Sefaira Systems
>>
>> Mobile: +44 (0)7887 059 722
>> Office: +44 (0)2037 147 619
>> Skype: andrew.corney.sefaira
>>
>> Sefaira - Sustainability. Performance. Design.
>>
>> *For company contact and registration information, please
>> visit: http://www.sefaira.com/info/contact
>> <http://www.sefaira.com/info/contact>*
>>
>> *Check out our latest webinar showcasing the product here
>> <https://vimeo.com/130461932>. Subscribe here
>> <http://www.sefaira.com/subscribe-from-email/> to our bi-weekly newsletter.*
>>
>
>
> _______________________________________________
> Bldg-sim mailing list
> http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
> To unsubscribe from this mailing list send  a blank message to
> BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG
>
>


-- 

James V Dirkes II, PE, BEMP, LEED AP
CEO/President
The Building Performance Team Inc.
1631 Acacia Dr, GR, Mi 49504

Direct: 616.450.8653
jim at buildingperformanceteam.com

Website <http://buildingperformanceteamcom>l  LinkedIn
<https://www.linkedin.com/pub/jim-dirkes/7/444/413>

 Life is not easy.  It’s never been easy. Expecting it to be easy is not a
healthy attitude.
Relax. Refresh. Regroup. Carry on.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150721/c0eecb1a/attachment.htm>