Installation of direct gas piping, Determine the supply gas requirements, Install additional regulator if required – Greenheck Fan Make-Up Air Unit VSU User Manual

Page 6: Connect the supply gas line

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6

Model VSU Make-Up Air

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Installation of Direct Gas Piping

IMPORTANT

All gas piping must be installed in accordance

with the latest edition of the National Fuel Gas

Code ANSI/Z223.1 and any local codes that may

apply. In Canada, the equipment shall be installed

in accordance with the Installation Code for Gas

Burning Appliances and Equipment (CGA B149)

and Provincial Regulations for the class. Authorities

having jurisdiction should be consulted before

installations are made.

WARNING

All components of this or any other gas-fired heating

unit must be leak tested prior to placing the unit

into operation. A soap and water solution should be

used to perform this test. NEVER test for gas leaks

with an open flame.

WARNING

If pressure testing in excess of 1/2 psig (3.5 kPa),

the heater and manual shutoff valve must be

disconnected from the supply gas line.

WARNING

If pressure testing at or below 1/2 psig (3.5 kPa), the

heater must be isolated from the supply gas line by

closing its manual shutoff valve.

IMPORTANT

All piping should be clean and free of any foreign

matter. Foreign material entering the gas train can

damage the valves, regulators and burner.

IMPORTANT

Do NOT connect the unit to gas types other than

what is specified and do NOT connect the unit to

gas pressures that are outside of the pressure range

shown on the label.

NOTE

When connecting the gas supply, the length of the

run must be considered in determining the pipe size

to avoid excessive pressure drop. Refer to a Gas

Engineer’s Handbook for gas pipe capacities.

1. Determine the Supply Gas
Requirements

The unit’s direct gas nameplate states the requirements
for the gas being supplied to the unit. The direct gas
nameplate is located on the outside of the unit on the
control center side.

Type of gas

“ W.C.

“ W.C.

“ W.C.

F

PSI

“ W.C.

“ W.C.

MAX BTU/HR
BTU/H MAX

NORMAL MANIFOLD
PRESSURE
PRESSION DÕADMISSION
NORMALE

MIN GAS
PRESSURE
PRESSION DE GAZ

MIN BURNER
PRESSURE DROP
PERTE MIN DE PRESSION
DANS LE BRULEUR

TYPE OF GAS
NATURE DU GAZ

MIN BTU/HR
BTU/H MIN

MIN GAS PRESSURE
FOR MAX OUTPUT
PRESSION DE GAZ MIN
POUR PUISSANCE MAX

MAX BURNER
PRESSURE DROP
PERTE MAX DE PRESSION
DANS LE BRULEUR

MAX GAS
PRESSURE
PRESSION DE GAZ
MAX

DESIGN ∆T
∆T NORMALE

EQUIPPED FOR

CONCU POUR

SCFM

“ W.C.

EXTERNAL STATIC PRESSURE

PRESSION STATIQUE EXTERIEURE

AGAINST

CONTE

Maximum gas pressure

Minimum gas pressure for

maximum output

2. Install Additional Regulator if Required

When the supply gas pressure exceeds the maximum
gas pressure shown on the direct gas nameplate, an
additional regulator (by others) is required to reduce
the pressure. The regulator must have a listed leak
limiting device or it must be vented to the outdoors.

3. Connect the Supply Gas Line

A manual shut off valve (gas cock), 1/8 in. plugged
test port and 6 in. drip leg must be installed prior to
the gas train. The valve and the test port must be
accessible for the connection of a test gauge. Supply
gas connections must be made by a qualified installer
and are not furnished by Greenheck.

To

Controls

Gas Cock

From

Gas

Supply

6 in. Trap

1/8 in. Plugged Tap

Ground Joint Union

Supply Gas Line

NOTE

The regulator located inside the unit is used to

adjust the unit’s maximum output temperature.

Direct Gas Nameplate

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