Air Change Requirement

[mechbuild]

Hello everybody,
At present, I am designing a facility where dead bodies are brought for washing and finally sent to the visiting room where the relatives will have last look at it.

As per Ahsrae, we need to maintain min.10 air change rate (100% fresh air) in this washing area,due to this, huge amount of conditioned air to be supplied and exhausted and eventually, the the chiller capacity is becoming almost double with this ACH as compared to the normal design (by considering load from building envelope and occupants).

By considering 10 ACH: Plant Capacity = 240 Tons

By considering load due to building envelope and occupants: Plant Capacity = 165 Tons.

Can anybody advice me of reducing plant load without compromising air change requirement.

Thanks and regards,

 

[cdxx139]

Use energy recovery. A wheel will give you 3-8% crossover contamination (without purge). If this is not acceptable (it is acceptable for lavatories), then go with a flat plate. This will give you 0% contamination, but only for sensible heat.

 

[AbbyNormal]

Renewaire

They have crossflow HX`s with some latent transfer

The way we build has a far greater impact on our comfort, energy consumption and IAQ, than any HVAC system we install

 

[ChrisConley]

Have you seen any of those 'latent' plate HXs in action Abby? The last time I looked at one my thought was that it kinda looked like soggy carboard being used to transfer heat and moisture. Haven't specified one yet.

 

[AbbyNormal]

lol, actually cardboard would work

Poor efficiency compared to a wheel, but less moving parts, no cross contamination.

If you build an ERV with a wheel right you can make clean air leak towards the exhaust side.

I am testing out a wheel from roof top systems in my own home down here.

The way we build has a far greater impact on our comfort, energy consumption and IAQ, than any HVAC system we install

 

[MintJulep]

Is there a (hopefully low) diversity factor that could be applied?

Why is is necessary to have 100% OA at times when the space is not being used for it's design purpose?

 

[sridhar1312]

100%Fresh air is taken only to prevent smaell/odor form the dead corpse.
You can use the heat pipe to recover the heat from the exust air so that you can precool the Fresh air and reduce the load on the chiller.