Trane WSHP-DS-6 manual Fresh Air, Ventilation, Application, Considerations, Typical Benefits

Application	Fresh Air
Considerations	Ventilation

Fresh Air Ventilation

with Water-to-Water Units

Exhaust

Air Fresh

Air

	Water-Out
	(source)
Water-Out	Water-In
(load)
	(source)
	Water-In
	(load)

Geothermal Space

Heating and Cooling

Water-to-Water

and Fresh Air

Ventilation

Geothermal energy systems take advantage of the fact that subsurface earth temperatures are constant year-round, which makes the earth an ideal heat source and heat sink for heat pumps.

The above design goes further than just space heating and cooling. Fresh air ventilation is achieved by using Trane water-to-water units teamed with a hydronic outside air unit, and exhaust air unit to meet total building requirements.

In the cooling season, the evaporator water from the heat pumps is circulated through a hydronic coil in the makeup air unit to provide cooling and dehumidification. The condenser water is used to provide reheat

energy to temper the ventilated air in accordance with the building needs. After leaving the reheat hydronic coil, the condenser water is then returned to the building loop for further heat rejection.

In heating, the water-to-water units switch to hot water generation. The water for ventilation air tempering first circulates through the hydronic coil to the exhaust air unit to pick up heat from the building exhaust airstream. The water then circulates through the water-to- water heat pumps for further heat introduction before being used by

(Closed) Ground

Loop Heat

Exchanger

the makeup air unit hydronic coil to heat the makeup air to maintain building requirements. This ventilation system incorporates its own constant volume pumps to pull system water off the loop and return it. There is no need for additional heat injection using boilers for this system. (See Page 14 for mechanical example).

Typical Benefits

θAnnual energy savings means lower energy costs

θBuilding comfort and climate control

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