882108-YIM-B-1012
Johnson Controls Unitary Products 7
GENERAL
York Model Z42/Z33/Z34 units are single package cooling
only or cooling with gas, electric, hot water or steam heating
designed for outdoor installation on a rooftop and for non-res-
idential use.
The units are completely assembled on rigid, permanently
attached base rails. All piping, refrigerant charge, and electri-
cal wiring is factory installed and tested. The units require
electric power, gas, steam, or hot water connections and duct
connections. Gas fired units also require installation of a flue
gas outlet hood.
Reference R-410A Quick Reference Guide, Figure 55 for
R-410A Refrigerant information.
SAFETY CONSIDERATIONS

NOTES, CAUTIONS AND WARNINGS

Installer should pay particular attention to the words: NOTE,
CAUTION, and WARNING. Notes are intended to clarify or
make the installation easier. Cautions are given to prevent
equipment damage. Warnings are given to alert installer that
personal injury and/or equipment damage may result if instal-
lation procedure is not handled properly.

GAS FIRED MODELS

DO NOT store or use gasoline or other flammable vapors and
liquids in the vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance. Do not touch any electrical
switch. Do not use any phone in your building. Immediately
call your gas supplier from a neighbor’s phone. Follow the
gas supplier’s instructions. If you cannot reach your gas sup-
plier, call the fire department.

ALL MODELS

Installation and servicing of air conditioning equipment can
be hazardous due to system pressure and electrical compo-
nents. Only trained and qualified service personnel should
install, repair or service air conditioning equipment.
Untrained personnel can perform basic maintenance func-
tions of cleaning coils and filters and replacing filters. All other
operations should be performed by trained service personnel.
When working on air conditioning equipment, observe pre-
cautions in the literature, tags and labels attached to the unit
and other safety precautions that may apply.
Follow all safety codes, including ANSI Z223.1-Latest Edi-
tion: wear safety glasses and work gloves; use quenching
cloth for unbrazing operations; have fire extinguisher avail-
able for all brazing operations.

INSPECTION

As soon as a unit is received, it should be inspected for possi-
ble damage during transit. If damage is evident, the extent of
damage should be noted on the carrier’s freight bill. A sepa-
rate request for inspection by the carrier’s agent should be
made in writing.
The furnace and its individual shut-off valve must
be disconnected from the gas supply piping sys-
tem during any pressure testing of that system at
test pressures in excess of 0.5 psig. Pressures
greater than 0.5 will cause gas valve damage
resulting in a hazardous condition. If gas valve is
subjected to a pressure greater than 0.5 psig, it
must be replaced. The furnace must be isolated
from the gas supply piping system by closing its
individual manual shut-off valve during any pres-
sure testing of that system at test pressures equal
to or less than 0.5 psig.
This Furnace is not to be used for temporary heat-
ing of buildings or structures under construction.
This system uses R-410A Refrigerant which oper-
ates at higher pressures than R-22. No other
refrigerant may be used in this system. Gage sets,
hoses, refrigerant containers and recovery sys-
tems must be designed to handle R-410A. If you
are unsure, consult the equipment manufacturer.
Failure to use R-410A compatible servicing equip-
ment may result in property damage or injury.
Before performing service or maintenance opera-
tions on unit, turn off main power switch to unit.
Electrical shock could cause personal injury.
Improper installation, adjustment, alteration, ser-
vice or maintenance can cause injury or property
damage. Refer to this manual. For assistance or
additional information consult a qualified installer,
service agency or the gas supplier.