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• Industrial Heaters

• Forced Air

• Convection

• Radiant

• Commercial Heaters

• Forced Air

• Convection

• Radiant

Comfort HeatersOverview

CVEP CXH

HCH KUH

Convection Heaters

Convection heat is the transfer of heat fromthe heater to surrounding air by the naturalcirculation of air through the heater. In freeor natural convection, the air motion is aresult of gravitational forces where theheated air is lighter than the cooler air. Theheated air rises from the top of the heaterand is replaced by cooler air which entersfrom the bottom. This air current deliversthe heat to the surrounding room. Indi-vidual convection heaters are a commonheat source in small areas, but whencombined as multiple heaters can heat largeareas as well.

Forced Air Blower Heaters

Adding a fan to a heater creates artificial airmovement. This air movement allows for amore compact heater than the convectionheater since rapidly moving air removes theheat from the heater surface more quickly.The forced air heater forces air over verylong distances and is usually the choice forheating larger areas.

ChromaStar

Chromalox electric comfort heaters provideefficient, economical heat for commercial andindustrial applications. Three basic types ofheaters are convection, forced air andradiant, with combinations often used. Theyapply safe, clean, fast heat and theirheavy-duty construction affords long,dependable service.

The following descriptions aid in determiningwhat methods of heating will provide you thebest solution for any given situation.

Radiant Heaters

Similar to the sun’s heat, infrared heatingheats people and objects rather than air orspace. Radiant heat is less affected by draftsand large air movements. When usingoverhead infrared to heat an entire building,direct radiated heat from the heater passesthrough the air to heat floors, walls,machinery and people. These heated objectsthen transfer heat to the air by naturalconvection and secondary radiant heat.Available in portable and stationary configu-rations, Chromalox radiant heaters are idealfor spot heating cold areas like shippingdocks and outdoor work sites when properlyshielded from the wind; for freeze protectingvalves, pumps, hoppers and machinery; or tothaw frozen pipes, downspouts andradiators. Radiant heat generates no noise,fumes or flames.

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• Methods of Heat Transfer

• Convection Heating

• Forced Air Heating

• Radiant Heating

• Heat Requirements

• Application Tips

Comfort HeatersApplication Guidelines

Applications

Methods of Heat Transfer — To understandwhich method of comfort heating best meetsyour application it is important to understandthe basic methods of heat transfer. Heattransfer is accomplished by Conduction,Convection or Radiation.

Conduction is defined as transferring heatthrough a conducting medium by way ofdirect contact.

Convection heat involves using a source ofheat to warm the air and create a desiredcomfort level around people. Heated air iscirculated by fans or blowers to generallysurround a normally enclosed area. Homeheating with a forced-air furnace is an exampleof convection heat.

Radiant or Infrared heat uses invisibleelectromagnetic waves from an energy source.The perfect example of electro-magneticinfrared energy is heat from the sun. In aninfrared system, these energy waves arecreated by a heat source - quartz lamp, quartztube, metal rod - which are directed byoptically designed reflectors toward or ontothe object or person. A fireplace is a familiarform of radiant heat.

Reasons to Use Convection Heating:

• Small Spaces and Rooms

• Quiet Operation

• Special Purposes like Cranes and PumpRooms.

Reasons to Use Forced Air, Blower Heating:

• High Heat Output in a Small Space

• Large Areas Require Air Movement toDistribute Heat

• Primary and Supplemental Heating.

Reasons to Use Radiant Heating:

• Gives Sunshine Like Warmth

• Heats People and Objects rather than Air orSpace

• Good for Supplemental Heating.

Determining the Heat Requirement — To getan approximate sizing of the heating require-ments for a room, the following guide may beutilized. For a more detailed analysis it isrecommended that the ASHRAE guidelines befollowed when performing an analysis for acomplete building. Your Local ChromaloxSales office can assist you in sizing yourapplication with a computer sizing tool that isdesigned to perform room-by-room heat lossestimates. When sizing the job, the first step isto determine the construction data and sizingrequirements. You will need to collect thefollowing information:

• Voltage and phase

• Length, width and height of building

• R-factor for ceilings and walls

• Air changes or how much fresh air isbrought in per hour

• Outside lowest temperature

• Desired inside temperature

• Size and number of windows and doors.

If a quick estimate is sufficient, then consultthe Comfort Heating Chart in the Technicalsection of this catalog.

Application Tips

Small Rooms can be heated by a one (1) unitheater. Where two (2) walls are exposed,heater should be mounted as shown.

Air Volume — To prevent air stratification,total CFM capacity of all units should circulatethe room air volume at least 3 times per hour.Units should be located so their air streamswipe exposed walls without blowing directly atthem.

In Multiple Unit Heater Installations locateunits so each unit supports the air streamfrom another, thus setting up circulatory airmovement.

In Warehouse Type Applications for maintain-ing minimum temperature, one or more largeheaters can be used to reduce initial installa-tion expense.

For Individual Space total heating capacity iscalculated in the conventional way, usingformulas in the ASHRAE “Guide” or thosefound in the NEMA handbook.

For Pedestrian Entryways when heatingcapacity is not known, a “rule of thumb” is5000 watts per door.

Loading Docks — Unit heaters are used tocombat cold air inrush when loading dockdoors are opened. For such applications, oneor more units should be arranged to blowwarm air across the opening, not toward it.

Harsh and Special Environments may requirecorrosion resistant and/or explosion proofheaters — see the Selection Guidelines on thefollowing page.

Often a Portable Heater or heaters can solve aunique comfort heating situation temporarilyor help determine the requirement forpermanently located heaters to achieve thedesired comfort levels.

Controls and Thermostats are vital to solvinga heating situation. See the Controls section ofthis catalog for more information, especiallytype WR80, WR90, WT, WTL, WR80-EP,WCRT and RTC thermostats.

Large Rooms require multi-unit installations.Number and capacity of units will be deter-mined by volume of building and square feetof floor area to be heated. Arrange units toprovide perimeter air circulation.

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Comfort HeatersSelection GuidelinesApplication Tips

Radiant Infrared Comfort Heaters can helpmany unique heating situations.

Heats People Without Heating Air — Infraredtravels through space and is absorbed bypeople and objects in its path. The air does notabsorb infrared energy. With convectionheating the air itself is warmed and circulated,however, warm air always rises to the highestpoint of a building. With Infrared comfortheating, the warmth is directed and concen-trated at the floor and people level where it isreally needed.

Low Maintenance — Electric infrared isstrictly a resistance type heat. There are nomoving parts or motors to wear out; no airfilters or lubrication required. Periodiccleaning of the reflectors and heat sourcereplacement is all that is required.

Clean — Electric infrared, like other forms ofelectric heating, is the cleanest method ofheating. There are no by-products of combus-tion as with fossil fuel burning units. Electricinfrared adds nothing to the air nor takesanything from it.

Safe

• No open flames

• No moving parts to malfunction

• No fuel lines to leak

• No toxic by-products of combustion

• UL available on some models

The Technical section of this catalog givesadditional information on “Radiant InfraredHeating — Comfort Heating”

For outdoor applications, consult your LocalChromalox Sales office.

Industrial Horizontal Blower 2.6 - 45 LUH F-4Horizontal Blower 2.6 - 45 KUH F-8High Capacity Horizontal 2 - 50 UB F-12Vertical Delivery 5 - 50 VUH F-17

Harsh Environment Corrosion Resistant 2 - 39 HDH F-21Explosion Proof 3 - 35 CXH-A F-23

Portable Portable Salamander 7.5 - 30 DRA F-29Portable Blower 1.9 - 4 HF F-32

Commercial Cabinet Console 2 - 18 CCH F-33Wall Blower 1.5 - 4.8 RFI F-37Fintube® Air Duct 10 - 533 DH F-38Fan Forced Wall 0.5 - 20 WHC F-41Fan Forced Floor 0.375 - 1.5 FFIH F-42Fan Forced Kick Space 0.450 - 1.8 CKH F-43

Forced Air Heaters — Selection GuidelinesApplication Feature kW Model Page

Industrial Wall Mounted 0.5 - 5.0 HCH F-44Without Thermostat 0.25 - 0.5 EH F-47With Thermostat 0.5 - 1.0 HVT F-47Horizontal 1 - 3 H F-48Vertical 2 - 4.5 V F-49

Special Purpose Pump House 0.5 CPHH F-50Institutional 0.2 - 1.5 ICH F-51

Harsh Environment Explosion Proof 1.6 - 9.0 CVEP F-52Explosion Proof - Single 0.2 - 1.0 FPEP F-57Explosion Proof - Dual 1.5 CEP-15 F-57

Commercial/ Draft Barrier 0.5 - 2.5 CAF-6 F-58Architectural Slope Top 0.5 - 2.5 CCAS-8 F-60

Square Top 1.1 - 6.0 CAF-12 F-64Slope Top 1.1 - 6.0 CCAS-12 F-62Cabinet 1.5 - 6.0 CAF-20 F-66

Convection Heaters — Selection GuidelinesApplication Feature kW Model Page

Industrial/ Portable or Ceiling Mount 1.5 - 13.5 ChromaStar F-68Commercial Overhead 1.2 - 3.6 RBC-3 F-74

Single Fixed Element 0.8 - 3.6 SKR F-76Single Fixed Element 0.8 - 1.8 KR F-77

Radiant Heaters — Selection GuidelinesApplication Feature kW Model Page

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