Thermo Products CDX3-75N, CHX3-75N, CHX3-125N, CDX3-125N, CHX3-100N, CDX3-100N operation manual

Page 36
Manual background

All installations and services must be performed by qualified service personnel.

Figure 20

3. USE OF NON-THERMO PRIDE FILTER RETENTION MEANS

If a method other than the Thermo Pride filter rack is selected for retention of the filter and/or use of a different filter type is desired, see Table 3 for minimum size guidelines for selecting a filter system for the CHX3 or CDX3 furnaces.

MINIMUM FILTER AREA REQUIRED (LENGTH X WIDTH, SQ. IN.)

TABLE 3

FILTER TYPE

MAXIMUM

Required CFM / (Filter Velocity Rating x 144) = min. filter

 

RATE

(in2)

 

 

 

 

AIR VELOCITY

 

 

 

 

 

 

 

FURNACE MODEL

 

 

 

CHX3,CDX3-75

CHX3,CDX3-100

 

CHX3,CDX3-125

*THERMO

600 FT./MIN.

254 IN.2*

328 IN.2*

 

402 IN.2*

PRODUCTS

 

 

 

 

 

SUPPLIED

 

 

 

 

 

PERMANENT FILTER

 

 

 

 

 

STANDARD

500 FT./MIN.

304 IN.2

394 IN.2

 

484 IN.2

PERMANENT FILTER

 

 

 

 

 

DISPOSABLE TYPE

300 FT./MIN.

506 IN.2

656 IN.2

 

804 IN.2

FILTER

 

 

 

 

 

*The Thermo Products supplied filter can be cut to size to fit other filter retention systems as long as the minimum size requirement is met. NOTICE: Any internal stiffeners used in the filter must not be removed, although they can be cut to size as needed.

NOTICE: The filter areas in table 3 are the minimum areas required based on the CFM generated by the furnace for standard heating speeds only. The following formula can be used to determine the minimum filter area required for cooling if the unit is equipped with cooling. This value should then be compared to the value shown in table 3 and the larger of the two should then be used for determining the minimum filter area required for that installation.

30

Image 36
Contents MODELS OR LP GAS PROPANE CDX3-75N CDX3-100N CDX3-125NTWO STAGE CONDENSING GAS FURNACE I. SAFETY INFORMATION This and the previous page contain reproductions of the various warning and instruction labels placed on the Thermo Pride Two Stage Condensing Gas Furnaces. Please read and comply with the contents of these labels 1.A windows be opened The CHX3/CDX3 furnace models are sealed combustion design, which does not require an air shutter adjustment air shutters are not used for proper flame characteristics. Burner box access cover must always be secured with all screws in place and tightened before operating furnace INDEX SECTIONBEGINNING PAGE II. FURNACE SPECIFICATIONS CHX3 SERIES CDX3 SERIES INSTALLATION PARTS PACKAGES - CHX3-75 INSTALLATION PARTS PACKAGES - CDX3-75 Grounding instructions III. GENERAL INSTALLATION B. FURNACE LOCATION B1. CDX3 HORIZONTAL APPLICATIONPage PVC Pipe Designation Maximum Quantity of Elbows E.Direct Venting Through a Sidewall Outside Combustion Air Intake RH viewc.The vent terminal shall not be located Page E1. Single-PipeSidewall Venting Option 5.Optional Direct Vent Terminations Install these optional kits according to the instructions provided with each kit. The location and clearance requirements are identical to those of the standard vent terminations described in this manual 1.Figures 6B, 7, and 8 follow depicting typical exhaust vent and air intake connections for the furnace model series CHX3 and the CDX3, respectively, as well as a list of required parts to correctly install each system Page Applications Figure 9 Typical Internal Vent Piping Arrangement for theFurnace Model Series CHX3 3. Connecting The Combustion Air Intake Piping I.CONDENSATE DRAIN LINE AND TRAP ASSEMBLY Figure 14. TRAP ASSEMBLY MOUNTED ON CHX3Figure 15. TRAP ASSEMBLY MOUNTED ON CDX3 2.Determine on which side of furnace the condensate disposal line is to be run NOTICE On CHX3/CDX3’s this must be the same side as the flue outlet or bottom of unit. Attach the condensate trap to the furnace casing using the #8x3/4” sheet metal screws provided in the parts package. Pilot holes are provided on both sides of the casing for mounting J. GENERAL GAS PIPING J1. REQUIREMENTS AND SIZING OF DUCT WORK Figure 18A TABLE 2A K. FILTERS 1. CHX3 MODELS HIGHBOYS 2. CDX3 MODELS COUNTERFLOWSPage L. WIRING Table 4A S7 DIP Switch Switch SettingsOptions Time2-StageBlower Settings from factory Table 4C IV. STARTING THE UNIT A. SEQUENCE OF OPERATIONS IF NOT IF THERMOSTAT W2 CONTACTS ARE CLOSED OTHERWISE B. INITIAL START UP OPERATING INSTRUCTIONSC. Measuring And Adjusting Heat Input Rate Observe the following precautions when measuringA.Burner manifold pressure with a pressure gauge B.Gas flowrate by clocking gas meterNOTICE A U-tubemanometer, measuring pressure in inches of water column, is recommended for all gas pressure measurements. However, an aneroid pressure gauge, in good working condition, capable of reading pressure changes of 0.05 in. W.G., or less, that was recently calibrated within the last year, is a satisfactory alternate. These two 2 devices will be considered as equivalent and interchangeable. Either device is referred to below as a “pressure gauge” Heat input rate in BTUH = Page 21.Go to Checkout Procedure below Checking The Burner FlameCheckout Procedure TABLE 6 - CONVERTING GAS FLOW RATE D. FURNACE CHECKOUT PROCEDURE V. INSTALLERS INSTRUCTIONS TO USERFigure VI. TROUBLESHOOTING DIAGNOSTIC FEATURES Power must be disconnected before servicingTROUBLESHOOTING GUIDE IS INDUCER RUNNING ON LOW SPEED? YES DOES THE HOT DO BURNERS STAY LIT PAST PROOF OF FLAME CHECK? REPLACE THE 50V51-843CONTROL DOESBURNERSHUT OFF Appendix -AReplacement Parts List Page Page Page Appendix - B Wiring Diagrams