background image

A.  Where directly communicating with the outdoors through an

opening or where communicating to the outdoors through
vertical ducts as shown in 

Figure 11

, each opening shall

have a minimum free area of 1 square inch for each 4,000
BTUH of total appliance input rating of all equipment in the
enclosure. 

Table 3

specifies the minimum area for 

each of the 2 combustion air openings and minimum round
duct diameter for direct openings and vertical ducting only.

B.  Where communicating with the outdoors through horizon-
tal ducts, each opening shall have a minimum free area of 1
square inch for each 2,000 BTUH of total appliance input rat-
ing of all equipment in the enclosure (see 

Figure 12

). 

Table 4

specifies the minimum area for each of the 2 combustion air
openings and minimum round duct diameter for horizontal
ducting only.

METHOD 2:

One permanent opening located within 12 inches of the top of
the enclosure, shall be permitted where the equipment has
clearances of at least 1 inch from the sides and back and 6
inches from the front of the appliance.  The opening shall di-
rectly communicate with the outdoors or communicate
through a vertical or horizontal duct to the outdoors or spaces
(crawl or attic) that freely communicate with the outdoors,
and shall have a minimum of:

TABLE 9 : MINIMUM FREE AREA REQUIRED  
FOR EACH OPENING (WHEN TWO OPENINGS  
ARE USED) WITH A FURNACE:                        

                            

1. LOCATED IN A CONFINED SPACE                                  
2. USING OUTDOOR AIR FOR COMBUSTION                                        
3. COMMUNICATING DIRECTLY TO THE  

OUTSIDE THROUGH AN OPENING OR  
THROUGH    A    VERTICAL    VENT    DUCT.*

Total  Input  for  

ALL  Gas  

Appliances  

(BTUH)  

Free  Area  for  

Each  Opening  

when  2  Separate  

Openings  are  

used  (sq  inches)   

Round  Pipe  Duct  

Diameter  ( Ver cal  

Duct  Only)  (inches)   

  50,000  

13  

5  

  75,000  

19  

5  

100,000  

25  

6  

125,000  

32  

8  

150,000  

38  

8  

  

  

  

  

  

  

  

  

  

TABLE 3: MINIMUM FREE AREA REQUIRED
FOR EACH OPENING (WHEN TWO OPENINGS
ARE USED) WITH A FURNACE:
1. LOCATED IN A CONFINED SPACE
2. USING OUTDOOR AIR FOR COMBUSTION
3. COMMUNICATING DIRECTLY TO THE

3. 

OUTSIDE THROUGH AN OPENING OR

3. 

THROUGH A VERTICAL DUCT.

16

Co

m

bu

sti

on

 A

ir

COMBUSTION AND VENTILATION AIR (cont.)

  

  

  
  

TABLE 1 0: MINIMUM FREE  AREA  REQUIRED  
FOR EACH OPENING (WHEN TWO OPENINGS  
ARE USED) WITH A FURNACE:                        

                              

1. LOCATED IN A CONFINED SPACE                                  
2. USING OUTDOOR AIR FOR COMBUSTION                                        
3. COMMUNICATING DIRECTLY TO THE  

OUTSIDE THROUGH A     H  ORIZONTAL   DUCT.  

Total  Input  for  

ALL  Gas  

Appliances  

(BTUH)  

Free  Area  for  

Each  Opening  

when  2  Separate  

Openings  are  

used  (sq  inches)  

Round  Pipe  Duct  

Diameter  

(Horizontal  Duct  

Only)  (inches)  

  50,000  

25  

  6   

  75,000  

38  

  8  

100,000  

50  

  8  

125,000  

63  

10  

150,000  

75  

10  

  

  

  

  

  

TABLE 4: MINIMUM FREE AREA REQUIRED

FOR EACH OPENING (WHEN TWO OPENINGS

ARE USED) WITH A FURNACE:

1. LOCATED IN A CONFINED SPACE

2. USING OUTDOOR AIR FOR COMBUSTION

3. COMMUNICATING DIRECTLY TO THE

3. 

OUTSIDE THROUGH A HORIZONTAL DUCT.

  

  

  
  

  

  

  

  

TABLE 1 1: MINIMUM FREE AREA REQUIRED  
FOR AN OPENING (WHEN O N

  E  OPENING IS  

USED) WITH A FURNACE:                                                                                                                        
1. LOCATED IN A CONFINED SPACE                                  
2. USING OUTDOOR AIR FOR COMBUSTION                                        
3. COMMUNICATING DIRECTLY TO THE  

*

Total  Input  for  

ALL  Gas  

Appliances  

(BTUH)  

Free  Area  for  an  

Opening  when   1  

Opening  is   used  

(sq  inches)  

Round  Pipe  Duct  

Diameter  (inches)   

  50,000  

25  

  6  

  75,000  

38  

  8  

100,000  

50  

  8  

125,000  

63  

10  

150,000  

75  

10  

  

     OUTSIDE.

TABLE 5: MINIMUM FREE AREA REQUIRED

FOR EACH OPENING (WHEN TWO OPENINGS

ARE USED) WITH A FURNACE:

1. LOCATED IN A CONFINED SPACE

2. USING OUTDOOR AIR FOR COMBUSTION

3. COMMUNICATING DIRECTLY TO THE

3. 

OUTSIDE THROUGH A HORIZONTAL DUCT.

COMBUSTION AIR REQUIREMENTS: CONFINED AND 
UNCONFINED SPACES

GAS

WATER

HEATER

FURNACE

12”

MAX

12”

MAX

NOTE:
EACH OPENING SHALL
HAVE A FREE AREA OF
NOT LESS THAN ONE
SQUARE INCH PER
1,000 BTU PER HOUR OF
THE TOTAL INPUT
RATING OF ALL
EQUIPMENT IN THE
ENCLOSURE, BUT NOT
LESS THAN 100
SQUARE INCHES.

 

 

 

 

ST-A1227-01

FIGURE 10

NON-DIRECT VENT
AIR FROM 
HEATED 
SPACE

VENT PENETRATIONS

FOR

 

NON

 

DIRECT

 

VENT

 

FURNACES

AIR FROM HEATED SPACE

Summary of Contents for (-)(-)80MDP050A30SA

Page 1: ...IZONTAL SERIES U L and or C S A recognized fuel gas and CO carbon monoxide detectors are rec ommended in all applications and their installation should be in accordance with the manufacturer s recomme...

Page 2: ...30 Humidifier 30 Filter 30 RXGW B01 Chimney Adapter 30 Four Inch Flue Adapter 30 11 TWINNING 32 Furnace Twinning Installations 32 Control Boards 33 35 12 HIGH ALTITUDE 36 Natural Gas at High Altitudes...

Page 3: ...r is correct open the carton and verify that the furnace rating label specifies the same furnace model number that is speci fied on the carton label If the model numbers do not match re turn the furna...

Page 4: ...hese publications are ANSI NFPA No 70 Latest Edition National Electrical Code NFPA90A Installation of Air Conditioning and Ventilating Sys tems NFPA90B Installation of warm air heating and air conditi...

Page 5: ...erature rise in heat record air temperature rise ______ Air temperature rise in cool record air temperature rise VENTING ______ Correct vent pipe diameter and length according to NFGC tables _________...

Page 6: ...IF THE FURNACE IS A MULTI STAGE FURNACE WARNING USE ONLY WITH THE TYPE OF GAS APPROVED FOR THIS FURNACE REFER TO THE FURNACE RATING PLATE WARNING NEVER TEST FOR GAS LEAKS WITH AN OPEN FLAME USE A COMM...

Page 7: ...AS ALL JOINTS SEAMS AND OPENINGS IN THE EQUIPMENT AND DUCT MUST BE SEALED TO LIMIT THE MIGRATION OF TOXIC FUMES AND ODORS IN CLUDING CARBON MONOXIDE FROM MIGRATING INTO THE LIVING SPACE IF AIR MOVING...

Page 8: ...SITE SELECTION 1 Select a site in the building near the center of the pro posed or existing duct system 2 Give consideration to the vent system piping when se lecting the furnace location Be sure the...

Page 9: ...PLACEMENT OF COMBUSTIBLE MATERIALS ON AGAINST OR AROUND THE FURNACE JACKET CAN CAUSE AN EXPLOSION OR FIRE RESULTING IN PROP ERTY DAMAGE PERSONAL INJURY OR DEATH THE HOMEOWNER SHOULD BE CAUTIONED THAT...

Page 10: ...lbs MAY REQUIRE 3 TO 4 OR 3 TO 5 ADAPTER 4 ADAPTER INCLUDED WITH 801P UNITS MAY BE 0 WITH TYPE B VENT MAY BE 1 WITH TYPE B VENT LEFT SIDE REDUCED CLEARANCE IN SHIP WGTS FIGURE 4 UPFLOW HORIZONTAL DIME...

Page 11: ...Where the maximum airflow is 1800 CFM or more BOTH sides or the bottom must be used for the return air Do not take return air from the back of the unit NOTE DO NOT take return air from furnace rooms g...

Page 12: ...M FLANGES OF CABINET BEFORE THE UNIT IS INSTALLED LIFT UP PULL OUT 1 REMOVE 2 SCREWS LIFT BASE UP SLIDE FORWARD TO REMOVE 2 INSTALLATION IS REVERSE OF REMOVAL VERIFY REAR FLANGE IS SEALED PROPERLY AS...

Page 13: ...ustion gases from an adjacent fuel burning appliance NOTE Do not block furnace access with support rods Main tain clearances recommended in Figure 8 Allow enough space for proper service maintenance o...

Page 14: ...of all appliances in the space If the open space contain ing the appliances is in a building with tight construction contem porary construction outside air may still be required for the appliances to...

Page 15: ...inch of free area for each 1 000 BTUH of total input in the space Table 2 shows some typical examples of openings required for com bustion air openings required for a confined space B USING OUTDOOR AI...

Page 16: ...EACH OPENING WHEN TWO OPENINGS ARE USED WITH A FURNACE 1 LOCATED IN A CONFINED SPACE 2 USING OUTDOOR AIR FOR COMBUSTION 3 COMMUNICATING DIRECTLY TO THE 3 OUTSIDE THROUGH AN OPENING OR 3 THROUGH A VERT...

Page 17: ...S IS NOT A REQUIREMENT SEE PREVIOUS PAGE SINGLE ELBOW IS ALLOWED BUT MAY NOT PREVENT DEBRIS FROM BEING DROPPED INTO THE FURNACE GROUND OR SHELF SURFACE 6 MIN 6 MININUM CLEARANCE PVC DOUBLE ELBOW 8 SCR...

Page 18: ...attic must be ventilated by gable or soffit vents COMBUSTION AIR FROM ATTIC If attic combustion air is used the inlet air opening at the furnace must be protected from accidental blockage Install a 9...

Page 19: ...and or the Natural Gas Installation Code CSA B149 1 2 for proper installation practices NOTE Follow combustion air instructions as outlined in this man ual Single wall vent connectors to B 1 vent or m...

Page 20: ...not be greater than 75 percent of the vertical height of the vent Single appliance venting of a fan assisted furnace into a tile lined masonry chimney is prohibited The chimney must be lined with eith...

Page 21: ...R cont FIGURE 18 DEDICATED VENTING THROUGH CHIMNEY WITH B 1 VENT Combustion Air FIGURE 17 FRESH AIR INLET ST A1220 09 01 1 STANDARD 3 FLUE CONNECTION 2 4 ADAPTER OPTIONAL SEE NATIONAL FUEL GAS CODE FO...

Page 22: ...venting system NOTE Ensure existing venting system complies with latest addi tion of National Fuel Gas Code ANSI Z223 1 and all local codes regulations 1 Visually inspect the venting system for prope...

Page 23: ...N AIR AND TENDS TO COLLECT AT LOWER LEVELS MAKING IT MORE DIFFICULT TO SMELL AT NOSE LEVEL NATURAL GAS IS LIGHTER THAN AIR AND WILL RISE POSSIBLY ACCUMULATING IN HIGHER PORTIONS OF THE STRUCTURE IF A...

Page 24: ...3 feet to easily remove the control valve assembly Install a manual shut off valve in the gas line outside the furnace cas ing The valve should be readily accessible to turn the gas supply on or off I...

Page 25: ...TION TITLED HIGH ALTITUDE INSTALLATIONS OF THIS BOOK FOR INSTRUCTIONS WARNING NEVER PURGE A GAS LINE INTO THE COMBUS TION CHAMBER NEVER USE MATCHES FLAME OR ANY IGNITION SOURCE FOR CHECKING LEAK AGE F...

Page 26: ...With LP gas have the LP supplier adjust the line pressure at the regulator Manifold Gas Pressure Measurement Natural gas manifold pressure should be 3 5 w c for high fire and 1 8 w c for low fire LP g...

Page 27: ...r and the gas supply to the furnace 2 Remove the burner door from the furnace 3 Remove the burner assembly handle with care 4 Remove the two screws attaching the NOx insert retainer bracket to the cen...

Page 28: ...lly connected to line volt age prior to reversing the electrical connection 2 Disconnect the wires from the door switch 3 Remove the junction box from the furnace cabinet wall by re moving the two scr...

Page 29: ...d be sized as shown NOTE Do not use 24 volt control wiring smaller than No 18 AWG Install the room thermostat in accordance with the instruction sheet packed in the box with the thermostat Run the the...

Page 30: ...ach option humidifier or electronic air cleaner RXGW C01 4 INCH FLUE ADAPTER See Figure 26 Refer to Venting section of this manual for more information See National Fuel Gas Code for sizing options FI...

Page 31: ...HE FURNCE AT THE LOCATIONS PROVIDED CUT OUT USING EMBOSSED ANGLES AS A GUIDE FOR PROPER SIZE 23 X 14 ST A1220 07 00 RXGF CB 6625 7 5 5 FIELD SUPPLIED FILTER ST A1220 06 X0 FIGURE 26 FILTER LOCATIONS A...

Page 32: ...be adequate to provide correct airflow to each furnace for supply and return UT ELECTRONIC CONTROLS 1095 300 CONTROL BOARD 62 104059 01 1 Single Stage Operation a Control board ONE is on furnace conn...

Page 33: ...33 TWINNING CONTROL BOARDS Twinning FIGURE 27 UT ELECTRONIC CONTROLS 1095 300 CONTROL BOARD TWINNING CONNECTION SINGLE STAGE OPERATION ST A1205 05 X0...

Page 34: ...34 TWINNING CONTROL BOARDS cont Twinning FIGURE 28 UT ELECTRONIC CONTROLS 1095 300 CONTROL BOARD TWINNING CONNECTION ONE STAGE THERMOSTAT TIMED STAGING GAS HEAT OPERATION ST A1205 06 X0...

Page 35: ...35 TWINNING CONTROL BOARDS cont Accessories FIGURE 29 UT ELECTRONIC CONTROLS 1095 300 CONTROL BOARD TWINNING CONNECTION TWO STAGE OPERATION ST A1205 07 X0...

Page 36: ...Sea Level Heating Value 1050 Q 23 81 ft3 Natural Gas per hour From Table F 1 of Natural Fuel Gas Code Handbook 2002 3 5 w c column Orifice required at Sea Level 43 From Table F 4 of National Fuel Gas...

Page 37: ...90 FURNACE MODEL NATURAL GAS ORIFICE SELECTION BASED ON HEATING VALUE ELEVATION Table is derived from Appendix of the National Fuel Gas Code To determine the correct orifice for your installation con...

Page 38: ...e LP orifices are based on an 11 of water column pressure at the orifice which dif fers from products that use 10 of water column at the orifice This difference requires a deviation from the NFGC orif...

Page 39: ...spark igniter is energized to light the gas burners and stays energized for the up to 7 seconds after the gas valve opens 5 8 seconds after the gas valve opens the remote flame sen sor must prove fla...

Page 40: ...times in a row the control enters one hour lockout and fault codes 10 and 11 will be displayed alternately as described above 2 When flame is lost five times in a row the control enters one hour lock...

Page 41: ...our period will commence after flame is no longer detected Dead Blower has been detected main limit circuit open for more than 150 seconds When voltage has unexpectedly been detected on the gas valve...

Page 42: ...display orientation is with the control placed in a vertical orientation and the low voltage terminal block T2 is on the left Cool Blower Off Delay SW2 SW3 A means of selecting the cooling speed blowe...

Page 43: ...r amber L E D is provided to indicate flame sta tus When normal flame is sensed the flame L E D is con tinuously on The flame L E D will flash at a rate of one to four flashes per second if a weak fla...

Page 44: ...pressure Then replace the regulator cap securely Any necessary major changes in the gas flow rate should be made by changing the size of the burner orifices To change orifice spuds shut off the manual...

Page 45: ...local gas utility to obtain the yearly average heating value and orifice size required to fire each individual burner at 25 000 BTU HR NOTE Refer to the High Altitude Section of this manual and the Na...

Page 46: ...re needs to be adjusted Use lower speed tap on the multi speed blower IMPORTANT The measured temperature rise should be in the middle of the range IMPORTANT Some high efficiency filters have a greater...

Page 47: ...050314MSA 80MDP050A30SA 1 3 11 x 6 802PA075417MSA 80MDP075B30SA 802PA100521MSA 80MDP100C40SA 802PA125524MSA 80MDP125D50SA 1 2 11 x 7 1 2 11 x 10 3 4 11 x 10 802PA150524MSA 80MDP150D50SA 3 4 11 x 10 Lo...

Page 48: ...led to diagnose and or correct the source of tripping If this unit is mounted in a closet the door must be closed when making this check PRESSURE SWITCH This furnace is equipped with a normally open p...

Page 49: ...nd through it to keep from overheating CAUTION DO NOT OPERATE THE SYSTEM FOR EXTENDED PE RIODS WITHOUT FILTERS A PORTION OF THE DUST ENTRAINED IN THE AIR MAY TEMPORARILY LODGE IN THE AIR DUCT RUNS AND...

Page 50: ...replacement marking which can be obtained through the distributor if any are found to be illegible or missing REPLACEMENT PARTS Please visit www myrheem com myruud com for replace ment parts informati...

Page 51: ...ected by registers fans sunlight heat through walls pipes or wires in walls Check heat anticipator setting Furnace may need an isolation relay Check installation instructions under section titled Isol...

Page 52: ...52 Wiring Diagram FIGURE 34 FOR MODELS WITH UT ELECTRONIC CONTROLS 1028 928 INTEGRATED FURNACE CONTROL AND DIRECT SPARK IGNITION CM 0814...

Reviews: