(2.) Optional,
(3.) No basepan penetration, other than those authorized by the manufacturer, is permitted.
10.Component access panels (standard)
a.Cabinet panels shall be easily removable for servicing.
b.Unit shall have one factory installed,
c.Panels covering control box, indoor fan, indoor fan motor, gas components (where applicable), and com- pressors shall have a molded composite handles.
d.Handles shall be UV modified, composite. They shall be permanently attached, and recessed into the panel.
e.Screws on the vertical portion of all removable access panel shall engage into heat resistant, molded compos- ite collars.
f.Collars shall be removable and easily replaceable using manufacturer recommended parts.
23 81 19.13.I. Gas Heat
1.General
a.Heat exchanger shall be an induced draft design. Positive pressure heat exchanger designs shall not be al- lowed.
b.Shall incorporate a
c.Gas supply pressure at the inlet to the rooftop unit gas valve must match that required by the manufacturer.
2.The heat exchanger shall be controlled by an integrated gas controller (IGC) microprocessor.
a.IGC board shall notify users of fault using an LED
b.The LED shall be visible without removing the control box access panel.
c.IGC board shall contain algorithms that modify
d.Unit shall be equipped with
3.Standard Heat Exchanger construction
a.Heat exchanger shall be of the
b.Burners shall be of the
c.Burners shall incorporate orifices for rated heat output up to 2000 ft (610m) elevation. Additional accessory kits may be required for applications above 2000 ft (610m) elevation, depending on local gas supply condi- tions.
d.Each heat exchanger tube shall contain multiple dimples for increased heating effectiveness.
4.Optional Stainless Steel Heat Exchanger construction
a.Use energy saving,
b.Use a redundant main gas valve.
c.Burners shall be of the
d.All gas piping shall enter the unit cabinet at a single location on side of unit (horizontal plane).
e.The optional stainless steel heat exchanger shall be of the
f.Type 409 stainless steel shall be used in heat exchanger tubes and vestibule plate.
g.Complete stainless steel heat exchanger allows for greater application flexibility.
5.Optional Low NOx Heat Exchanger construction
a.Low NOx reduction shall be provided to reduce nitrous oxide emissions to meet California’s Air Quality Man- agement District (SCAQMD)
b.Primary tubes and vestibule plates on low NOx units shall be 409 stainless steel. Other components shall be aluminized steel.
6.Induced draft combustion motor and blower
a.Shall be a
b.Shall be made from steel with a
c.Shall have permanently lubricated sealed bearings.
d.Shall have inherent thermal overload protection.
e.Shall have an automatic reset feature.
581J
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