EXPLOSION-PROOF SERIES Convection Heater

HARSH ENVIRONMENT PRODUCTS

Product Overview

The QMark Explosion-Proof Series Convection Heater is designed for safe and efficient operation in hazardous environments. It offers robust construction and reliable performance for various industrial applications.

Key Features:

Wide Selection of Sizes: Four compact sizes are available, offering ratings from 500 to 9,500 watts to suit diverse space requirements.
Sloped Top Cabinet: This design prevents objects from being placed on top of the convector, ensuring unobstructed airflow and preventing potential overheating.
Single and Three-Phase Capability: A unique design allows for both single-phase and balanced three-phase loads to be handled by a single element.
Hazardous Atmosphere Ratings: The heaters are certified for use in hazardous locations, with three listings covering hazardous gases, vapors, and dust particles.

Hazardous Location Classifications

Applicable Classes:

Class I, Divisions 1 & 2, Groups B, C & D
Class II, Divisions 1 & 2, Groups E, F & G
Class I, Zones 1 & 2, Groups IIB & H2

Ideal Installation Spaces:

Battery Storage Areas
Chemical Plants
Coal Handling Facilities
Dry Cleaning Plants
Gasoline Fueling & Storage Areas
Grain Elevators
Oil Refineries
Paint Spraying & Storage Areas
Petrochemical Plants

Standard Construction Features

Grade A Nickel-Chromium heating coils insulated with ceramics and fitted with aluminum fins for efficient heat transfer.
Heavy gauge galvanized steel cabinet finished with a durable beige powder coat for enhanced longevity.
Integrated linear limit with automatic reset thermal cutout for safety and reliable operation.
Optional built-on contactor and transformer packages are available for larger single-phase and all three-phase units to simplify installation.

Specifications

Class I, Divisions 1 & 2, Groups B, C & D; Class I, Zones 1 & 2, Groups IIB & H2

Ignition Temperature Code T2A, 536° F (280°C)

Catalog No.	Volts	Phase	KW	Amps	Unit Size	Controls Only	Thermostat/Controls	Ship Wt.
QX-254-F0310052B	120	1	0.5	4.2	1	--	1024754	13 lbs
QX-254-F0310052C	208	1	0.5	2.4	1	--	1024754	13 lbs
QX-254-F0310052J	240	1	0.5	2.1	1	--	1024754	13 lbs
QX-254-F0310052N	277	1	0.5	1.8	1	--	1024754	13 lbs
QX-254-F0310102B	120	1	1.0	8.3	1	--	1024754	13 lbs
QX-254-F0310102C	208	1	1.0	4.8	1	--	1024754	13 lbs
QX-254-F0310102J	240	1	1.0	4.2	1	--	1024754	13 lbs
QX-254-F0310102N	277	1	1.0	3.6	1	--	1024754	13 lbs
QX-254-F0320182B	120	1	1.8	15.0	2	Not Required	S2	27 lbs
QX-254-F0320182C	208	1	1.8	8.7	2	Not Required	S2	27 lbs
QX-254-F0320182J	240	1	1.8	7.5	2	Not Required	S2	27 lbs
QX-254-F0320182N	277	1	1.8	6.5	2	Not Required	S2	27 lbs
QX-254-F0320182I	347	1	1.8	5.2	2	B2	B3	27 lbs
QX-254-F0320182U	480	3	1.8	2.2	2	B2	B3	27 lbs
QX-254-F0320182Z	600	3	1.8	1.8	2	B2	B3	27 lbs
QX-254-F0320252C	208	1	2.5	12.0	2	Not Required	S2	27 lbs
QX-254-F0320252D	208	3	2.5	6.9	2	B2	B3	27 lbs
QX-254-F0320252J	240	1	2.5	10.4	2	Not Required	S2	27 lbs
QX-254-F0320252N	277	1	2.5	9.0	2	Not Required	S2	27 lbs
QX-254-F0320252I	347	1	2.5	7.2	2	B2	B3	27 lbs
QX-254-F0320252U	480	3	2.5	3.0	2	B2	B3	27 lbs
QX-254-F0320252Z	600	3	2.5	2.4	2	B2	B3	27 lbs
QX-254-F0330362C	208	1	3.6	17.3	3	Not Required	S2	36 lbs
QX-254-F0330362D	208	3	3.6	10.0	3	B2	B3	36 lbs
QX-254-F0330362J	240	1	3.6	15.0	3	Not Required	S2	36 lbs
QX-254-F0330362N	277	1	3.6	13.0	3	Not Required	S2	36 lbs
QX-254-F0330362I	347	1	3.6	10.4	3	B2	B3	36 lbs
QX-254-F0330362U	480	3	3.6	4.3	3	B2	B3	36 lbs
QX-254-F0330362Z	600	3	3.6	3.5	3	B2	B3	36 lbs
QX-254-F0330442D	208	3	4.4	12.2	3	B2	B3	36 lbs
QX-254-F0330442J	240	1	4.4	18.3	3	Not Required	S2	36 lbs
QX-254-F0330442N	277	1	4.4	15.9	3	Not Required	S2	36 lbs
QX-254-F0330442I	347	1	4.4	12.7	3	B2	B3	36 lbs
QX-254-F0330442U	480	3	4.4	5.3	3	B2	B3	36 lbs
QX-254-F0330442Z	600	3	4.4	4.3	3	B2	B3	36 lbs
QX-254-F0340652D	208	3	6.5	18.0	4	B2	B3	60 lbs
QX-254-F0340652J	240	3	6.5	27.1	4	B2	B3	60 lbs
QX-254-F0340652N	277	1	6.5	23.5	4	B2	B3	60 lbs
QX-254-F0340652I	347	1	6.5	18.7	4	B2	B3	60 lbs
QX-254-F0340652U	480	3	6.5	7.8	4	B2	B3	60 lbs
QX-254-F0340652Z	600	3	6.5	6.3	4	B2	B3	60 lbs
QX-254-F0340752D	208	3	7.5	20.8	4	B2	B3	60 lbs
QX-254-F0340752J	240	1	7.5	31.3	4	B2	B3	60 lbs
QX-254-F0340752N	277	1	7.5	27.1	4	B2	B3	60 lbs
QX-254-F0340752I	347	1	7.5	21.6	4	B2	B3	60 lbs
QX-254-F0340752U	480	3	7.5	9.0	4	B2	B3	60 lbs
QX-254-F0340752Z	600	3	7.5	7.2	4	B2	B3	60 lbs
QX-254-F0340952D	208	3	9.5	26.4	4	B2	B3	60 lbs
QX-254-F0340952J	240	1	9.5	39.6	4	B2	B3	60 lbs
QX-254-F0340952N	277	1	9.5	34.3	4	B2	B3	60 lbs
QX-254-F0340952I	347	1	9.5	27.4	4	B2	B3	60 lbs
QX-254-F0340952U	480	3	9.5	11.4	4	B2	B3	60 lbs
QX-254-F0340952Z	600	3	9.5	9.1	4	B2	B3	60 lbs

Ignition Temperature Code T3A, 356° F (180°C)

Catalog No.	Volts	Phase	KW	Amps	Unit Size	Controls Only	Thermostat/Controls	Ship Wt.
QX-254-F0610052B	120	1	0.5	4.2	1	--	1024754	13 lbs
QX-254-F0610052C	208	1	0.5	2.4	1	--	1024754	13 lbs
QX-254-F0610052J	240	1	0.5	2.1	1	--	1024754	13 lbs
QX-254-F0610052N	277	1	0.5	1.8	1	--	1024754	13 lbs
QX-254-F0620142B	120	1	1.4	11.7	2	Not Required	S2	27 lbs
QX-254-F0620142C	208	1	1.4	6.7	2	Not Required	S2	27 lbs
QX-254-F0620142J	240	1	1.4	5.8	2	Not Required	S2	27 lbs
QX-254-F0620142N	277	1	1.4	5.1	2	Not Required	S2	27 lbs
QX-254-F0620142I	347	1	1.4	4.0	2	B2	B3	27 lbs
QX-254-F0630232B	120	1	2.3	19.2	3	Not Required	S2	36 lbs
QX-254-F0630232C	208	1	2.3	11.1	3	Not Required	S2	36 lbs
QX-254-F0630232D	208	3	2.3	6.4	3	B2	B3	36 lbs
QX-254-F0630232J	240	1	2.3	9.6	3	Not Required	S2	36 lbs
QX-254-F0630232N	277	1	2.3	8.3	3	Not Required	S2	36 lbs
QX-254-F0630232I	347	1	2.3	6.6	3	B2	B3	36 lbs
QX-254-F0630232U	480	3	2.3	2.8	3	B2	B3	36 lbs
QX-254-F0630232Z	600	3	2.3	2.2	3	B2	B3	36 lbs
QX-254-F0640322C	208	1	3.2	15.4	4	Not Required	S2	60 lbs
QX-254-F0640322D	208	3	3.2	8.9	4	B2	B3	60 lbs
QX-254-F0640322J	240	1	3.2	13.3	4	Not Required	S2	60 lbs
QX-254-F0640322N	277	1	3.2	11.6	4	Not Required	S2	60 lbs
QX-254-F0640322I	347	1	3.2	9.2	4	B2	B3	60 lbs
QX-254-F0640322U	480	3	3.2	3.8	4	B2	B3	60 lbs
QX-254-F0640322Z	600	3	3.2	3.1	4	B2	B3	60 lbs
QX-254-F0640502D	208	3	5.0	13.9	4	B2	B3	60 lbs
QX-254-F0640502J	240	1	5.0	20.8	4	Not Required	S2	60 lbs
QX-254-F0640502N	277	1	5.0	18.1	4	Not Required	S2	60 lbs
QX-254-F0640502I	347	1	5.0	14.4	4	B2	B3	60 lbs
QX-254-F0640502U	480	3	5.0	6.0	4	B2	B3	60 lbs
QX-254-F0640502Z	600	3	5.0	4.8	4	B2	B3	60 lbs

Class I, Divisions 1 & 2, Groups C & D; Class I, Zones 1 & 2, Groups IIB

Ignition Temperature Code T2A, 536° F (280°C)

Catalog No.	Volts	Phase	KW	Amps	Unit Size	Controls Only	Thermostat/Controls	Ship Wt.
QX-254-F0310053B	120	1	0.5	4.2	1	--	1007002	13 lbs
QX-254-F0310053C	208	1	0.5	2.4	1	--	1007002	13 lbs
QX-254-F0310053J	240	1	0.5	2.1	1	--	1007002	13 lbs
QX-254-F0310053N	277	1	0.5	1.8	1	--	1007002	13 lbs
QX-254-F0310103B	120	1	1.0	8.3	1	--	1007002	13 lbs
QX-254-F0310103C	208	1	1.0	4.8	1	--	1007002	13 lbs
QX-254-F0310103J	240	1	1.0	4.2	1	--	1007002	13 lbs
QX-254-F0310103N	277	1	1.0	3.6	1	--	1007002	13 lbs
QX-254-F0320183B	120	1	1.8	15.0	2	Not Required	S1	27 lbs
QX-254-F0320183C	208	1	1.8	8.7	2	Not Required	S1	27 lbs
QX-254-F0320183J	240	1	1.8	7.5	2	Not Required	S1	27 lbs
QX-254-F0320183N	277	1	1.8	6.5	2	Not Required	S1	27 lbs
QX-254-F0320183I	347	1	1.8	5.2	2	B2	B2S1	27 lbs
QX-254-F0320183U	480	3	1.8	2.2	2	B2	B2S1	27 lbs
QX-254-F0320183Z	600	3	1.8	1.8	2	B2	B2S1	27 lbs
QX-254-F0320253C	208	1	2.5	12.0	2	Not Required	S1	27 lbs
QX-254-F0320253D	208	3	2.5	6.9	2	B2	B2S1	27 lbs
QX-254-F0320253J	240	1	2.5	10.4	2	Not Required	S1	27 lbs
QX-254-F0320253N	277	1	2.5	9.0	2	Not Required	S1	27 lbs
QX-254-F0320253I	347	1	2.5	7.2	2	B2	B2S1	27 lbs
QX-254-F0320253U	480	3	2.5	3.0	2	B2	B2S1	27 lbs
QX-254-F0320253Z	600	3	2.5	2.4	2	B2	B2S1	27 lbs
QX-254-F0330363C	208	1	3.6	17.3	3	Not Required	S1	36 lbs
QX-254-F0330363D	208	3	3.6	10.0	3	B2	B2S1	36 lbs
QX-254-F0330363J	240	1	3.6	15.0	3	Not Required	S1	36 lbs
QX-254-F0330363N	277	1	3.6	13.0	3	Not Required	S1	36 lbs
QX-254-F0330363I	347	1	3.6	10.4	3	B3	B3S1	36 lbs
QX-254-F0330363U	480	3	3.6	4.3	3	B2	B2S1	36 lbs
QX-254-F0330363Z	600	3	3.6	3.5	3	B2	B2S1	36 lbs
QX-254-F0330443D	208	3	4.4	12.2	3	B2	B2S1	36 lbs
QX-254-F0330443J	240	1	4.4	18.3	3	Not Required	S1	36 lbs
QX-254-F0330443N	277	1	4.4	15.9	3	Not Required	S1	36 lbs
QX-254-F0330443I	347	1	4.4	12.7	3	B2	B3S1	36 lbs
QX-254-F0330443U	480	3	4.4	5.3	3	B2	B2S1	36 lbs
QX-254-F0330443Z	600	3	4.4	4.3	3	B2	B2S1	36 lbs
QX-254-F0340653D	208	3	6.5	18.0	4	B2	B2S1	60 lbs
QX-254-F0340653J	240	1	6.5	27.1	4	B2	B2S1	60 lbs
QX-254-F0340653N	277	1	6.5	23.5	4	B2	B2S1	60 lbs
QX-254-F0340653I	347	1	6.5	18.7	4	B2	B2S1	60 lbs
QX-254-F0340653U	480	3	6.5	7.8	4	B2	B2S1	60 lbs
QX-254-F0340653Z	600	3	6.5	6.3	4	B2	B2S1	60 lbs
QX-254-F0340753D	208	3	7.5	20.8	4	B2	B2S1	60 lbs
QX-254-F0340753J	240	1	7.5	31.3	4	B2	B2S1	60 lbs
QX-254-F0340753N	277	1	7.5	27.1	4	B2	B2S1	60 lbs
QX-254-F0340753I	347	1	7.5	21.6	4	B2	B2S1	60 lbs
QX-254-F0340753U	480	3	7.5	9.0	4	B2	B2S1	60 lbs
QX-254-F0340753Z	600	3	7.5	7.2	4	B2	B2S1	60 lbs
QX-254-F0340953D	208	3	9.5	26.4	4	B2	B2S1	60 lbs
QX-254-F0340953J	240	1	9.5	39.6	4	B2	B2S1	60 lbs
QX-254-F0340953N	277	1	9.5	34.3	4	B2	B2S1	60 lbs
QX-254-F0340953I	347	1	9.5	27.4	4	B2	B2S1	60 lbs
QX-254-F0340953U	480	3	9.5	11.4	4	B2	B2S1	60 lbs
QX-254-F0340953Z	600	3	9.5	9.1	4	B2	B2S1	60 lbs

Class I, Divisions 1 & 2, Groups B, C & D; Class II, Divisions 1 & 2, Groups E, F & G

Ignition Temperature Code T3C, 320° F (160°C)

Catalog No.	Volts	Phase	KW	Amps	Unit Size	Controls Only	Thermostat/Controls	Ship Wt.
QX-254-F0810054B	120	1	0.5	4.2	1	--	1007002	13 lbs
QX-254-F0810054C	208	1	0.5	2.4	1	--	1007002	13 lbs
QX-254-F0810054J	240	1	0.5	2.1	1	--	1007002	13 lbs
QX-254-F0810054N	277	1	0.5	1.8	1	--	1007002	13 lbs
QX-254-F0820104B	120	1	1.0	8.3	2	Not Required	S1	27 lbs
QX-254-F0820104C	208	1	1.0	4.8	2	Not Required	S1	27 lbs
QX-254-F0820104J	240	1	1.0	4.2	2	Not Required	S1	27 lbs
QX-254-F0820104N	277	1	1.0	3.6	2	Not Required	S1	27 lbs
QX-254-F0820104I	347	1	1.0	2.9	2	B2	B2S1	27 lbs
QX-254-F0830174B	120	1	1.7	14.2	3	Not Required	S1	36 lbs
QX-254-F0830174C	208	1	1.7	8.2	3	Not Required	S1	36 lbs
QX-254-F0830174D	208	3	1.7	4.7	3	B2	B2S1	36 lbs
QX-254-F0830174J	240	1	1.7	7.1	3	Not Required	S1	36 lbs
QX-254-F0830174N	277	1	1.7	6.1	3	Not Required	S1	36 lbs
QX-254-F0830174I	347	1	1.7	4.9	3	B2	B2S1	36 lbs
QX-254-F0830174U	480	3	1.7	2.0	3	B2	B2S1	36 lbs
QX-254-F0830174Z	600	3	1.7	1.6	3	B2	B2S1	36 lbs
QX-254-F0840324C	208	1	3.2	15.4	4	Not Required	S1	60 lbs
QX-254-F0840324D	208	3	3.2	8.9	4	B2	B2S1	60 lbs
QX-254-F0840324J	240	1	3.2	13.3	4	Not Required	S1	60 lbs
QX-254-F0840324N	277	1	3.2	11.6	4	Not Required	S1	60 lbs
QX-254-F0840324I	347	1	3.2	9.2	4	B2	B2S1	60 lbs
QX-254-F0840324U	480	3	3.2	3.8	4	B2	B2S1	60 lbs
QX-254-F0840324Z	600	3	3.2	3.1	4	B2	B2S1	60 lbs

Dimensions and Clearances

Size	L	H	D
1	26"	6"	4 1/2"
2	26"	16"	8"
3	39"	16"	8"
4	67 1/2"	16"	8"

Electrical Package Options

All single-phase heaters rated over 22 amps or 277 volts and all three-phase heaters require a magnetic contactor. Some electrical combinations will also require a control transformer. To simplify field installation, these accessories are factory-mounted on the heater cabinet and factory pre-wired (not available on Size 1 convectors).

Option Code	Description
B2	Electric Control Option* (without thermostat): Classes I and II, Groups B, C, E, D, F and G includes contactor and transformer (as required). Required for all three-phase and single-phase heaters over 22 amps or 277 volts.
B2S1	Thermostat & Controls*: Classes I and II, Groups C, D, E, F and G includes thermostat, contactor and transformer (as required).
B3	Thermostat & Controls (Group B)*: Classes I and II, Groups B, C, D, E, F and G includes thermostat, contactor and transformer (as required). Thermostat has internal set point.
S1	Thermostat Only*: Classes I and II, Groups C, D, E, F and G single-phase heaters rated up to 22 amps at 120-277 volts. Use remote room thermostat Catalog Number 1007002 for Size 1 convectors.
S2	Thermostat Only (Group B)*: Classes I and II, Groups B, C, D, E, F and G single-phase heaters rated up to 22 amps at 120-277 volts. Thermostat has internal set point. Use remote room thermostat Catalog Number 1024754 for Size 1 convectors.

*Not available on Size 1 Convectors.

Accessory Remote Thermostats

Catalog No.	Switch Type	Type	Rating	Temp Range	Description
1007002	Bimetal	SPDT	125-277V, 22A	50°-90°F (10°-32°C)	Class 1, Div. 1, Groups C & D \| Class II, Div. 1, Groups E, F, & G
QX-1024754	Bulb and Capillary	SPDT	120-240V, 25A	40°-120°F (5°-49°C)	Class 1, Div. 1, Groups B, C & D \| Class II, Div. 1, Groups E, F, & G
QX-1025396	with Internal Set Point Adjustment	SPST	277V, 22A	40°-120°F (5°-49°C)	Corrosion-Resistant Class 1, Div. 1, Groups B, C, & D \| Class II, Div. 1, Groups E, F & G

Thermostat Configuration Options

S1 / S2: Thermostat (External Set Point). These options utilize either a bimetal or bulb and capillary sensor for temperature control.

B2S1: Optional Built-on Thermostat (External Set Point) within a Control Package. Rated for Class I, Groups C & D | Class II, Groups E, F, & G.

B3: Control Package with Thermostat (Internal Set Point). Rated for Class I, Groups B, C & D | Class II, Groups E, F, & G.

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EXPLOSION-PROOF SERIES Convection Heater

HARSH ENVIRONMENT PRODUCTS

Product Overview

Key Features:

Hazardous Location Classifications

Applicable Classes:

Ideal Installation Spaces:

Standard Construction Features

Specifications

Class I, Divisions 1 & 2, Groups B, C & D; Class I, Zones 1 & 2, Groups IIB & H2

Ignition Temperature Code T2A, 536° F (280°C)

Ignition Temperature Code T3A, 356° F (180°C)

Class I, Divisions 1 & 2, Groups C & D; Class I, Zones 1 & 2, Groups IIB

Ignition Temperature Code T2A, 536° F (280°C)

Class I, Divisions 1 & 2, Groups B, C & D; Class II, Divisions 1 & 2, Groups E, F & G

Ignition Temperature Code T3C, 320° F (160°C)

Dimensions and Clearances

Electrical Package Options

Accessory Remote Thermostats

Thermostat Configuration Options

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