Aprilaire 8100 Balancing the System, Duct work Connections Without Forced Air, Equipment Required

MECHANICAL INSTALLATION (continued)

DUCTING (continued)

• The intake and exhaust hoods must be located at least 10 ft.
	Figure 18 – Intake and Exhaust Hoods
apart to avoid cross contamination.. (See Figure 18..)
• Intake and exhaust hoods should be above the exposed snow
line or a minimum of 18” above ground level, whichever is		INTAKE		EXHAUST
greater.. (See Figure 18..)
• The intake hood should be a minimum of 10 ft. from an appliance			10 FT MINIMUM
vent that exhausts toxic fumes.. The hood should not be installed	18 INCHES
	MINIMUM
near sources of pollution and/or extreme temperatures, such as			GROUND
furnace exhaust, car exhaust, dryer vents, etc..				90-1748

•Do not connect the ERV exhaust to any gas appliance flue.

•Do not connect the exhaust outlet into an attic, storage or garage space. Excess moisture could develop in these areas, possibly causing damage to the home..

•If not running continuously, a field supplied butterfly damper must be installed in the intake duct near the hood. (See Figure 17..)

Duct work Connections Without Forced Air

•All the ducting connection procedures apply, with the exception of the following changes:

•The fresh air supply can be ducted to various parts of the home, where fresh air is needed.

•It is recommended that no more than 3 fresh air supply ducts be used to assure adequate airflow.

•The total free area of supply grilles should not be less than 75 in2.. For example: Three supply ducts would require a minimum of 25 in2 of free area each..

•Do not place a supply outlet in the same room or in the vicinity of the stale air return from the house.

•It is recommended that the fresh air supply be in a hall or foyer to avoid drafts and blower noise in occupied areas.

BALANCING THE SYSTEM

In order for the ERV to perform effectively, the volume of fresh air supplied to the house must match the volume of stale air exhausted.. Because the duct work in the two airstreams will most likely be different, the system must be balanced.. Balancing is accomplished by installing dampers in both airstreams, measuring the airflow, and dampering down the airflow in the stream with the highest flow, until the airflow in both streams is the same..

The following procedure is the recommended method.. Other measuring instrumentation may be used if it is accurate enough to balance the airflow in the supply and exhaust streams to within 10% of each other..

Equipment Required

•Two Dwyer Magnahelic Differential Pressure Gauges; Series 2000, 0-0.25” w.c. (or equal). Note: Do not use a standard differential pressure gauge that reads above 0..25” w..c.. The reading will not be accurate for the airflow required by the ERV..

•Two Research Products’ airflow measuring devices, Part Number 5158.

•3/16” ID flexible tubing.

•Drill with 7/8” bit.

Before balancing the system, verify the following:

1.Make sure the EnergyMax Transfer Core and filters are installed correctly..

2.Check all duct work connections to be sure they are installed and sealed properly..

3.Fasten door securely to housing..

4.Place all dampers in the fully open position..

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