Sizing Between First and Second Stage Regulator*
Maximum Propane Capacities listed are based on 2 psig pressure drop at 10 psig setting. Capacities in 1,000 BTU/hour.
| Pipe or | | Tubing Size, O.D. Type L | | | Nominal Pipe Size | |
| Tubing | | | | Schedule 40 | |
| | | | | | | | |
| Length, | 3/8" | 1/2" | 5/8" | 3/4" | 7/8" | 1-1/8" | 1/2" | 3/4" | 1" | 1-1/4" | 1-1/2" |
| Feet |
| | | | | | | | | | | |
| 10 | 39 | 92 | 199 | 329 | 501 | 935 | 275 | 567 | 1,071 | 2,205 | 3,307 |
| 20 | 26 | 62 | 131 | 216 | 346 | 630 | 189 | 393 | 732 | 1,496 | 2,299 |
| 30 | 21 | 50 | 107 | 181 | 277 | 500 | 152 | 315 | 590 | 1,212 | 1,858 |
| 40 | 19 | 41 | 90 | 145 | 233 | 427 | 129 | 267 | 504 | 1,039 | 1,559 |
| 50 | 18 | 37 | 79 | 131 | 198 | 376 | 114 | 237 | 448 | 91 | 1,417 |
| 60 | 16 | 35 | 72 | 121 | 187 | 340 | 103 | 217 | 409 | 834 | 1,275 |
| 80 | 13 | 29 | 62 | 104 | 155 | 289 | 89 | 185 | 346 | 724 | 1,066 |
| 100 | 11 | 26 | 55 | 90 | 138 | 255 | 78 | 162 | 307 | 630 | 976 |
| 125 | 10 | 24 | 48 | 81 | 122 | 224 | 69 | 146 | 275 | 567 | 866 |
| 150 | 9 | 21 | 43 | 72 | 109 | 202 | 63 | 132 | 252 | 511 | 787 |
| 200 | 8 | 19 | 39 | 66 | 100 | 187 | 54 | 112 | 209 | 439 | 665 |
| 250 | 8 | 17 | 36 | 60 | 93 | 172 | 48 | 100 | 185 | 390 | 590 |
X. CIRCULATING AIR AND FILTERS
Ductwork - Air
WARNING
NEVER ALLOW THE PRODUCTS OF COMBUSTION, INCLUDING CARBON MONOXIDE, TO ENTER THE RETURN DUCTWORK OR CIRCULATION AIR SUPPLY.
Duct systems and register sizes must be properly designed for the CFM and external static pressure rating of the furnace. Ductwork should be designed in accordance with the recommended methods of “Air Conditioning Contractors of America” Manual D.
A duct system must be installed in accordance with Standards of the National Board of Fire Underwriters for the Installation of Air Conditioning, Warm Air Heating and Ventilating Systems. Pamphlets No. 90A and 90B.
A closed return duct system must be used, with the return duct connected to the furnace. NOTE: Ductwork must never be attached to the back of the furnace. Supply and return connections to the furnace may be made with flexible joints to reduce noise transmission. To prevent the blower from interfering with combustion air or draft when a central return is used, a connecting duct must be installed between the unit and the utility room wall. A room, closet, or alcove must not be used as a return air chamber.
When the furnace is used in connection with a cooling unit, the furnace should be installed in parallel with or on the upstream side of the cooling unit to avoid condensation in the heating element. With a parallel flow arrangement, the dampers or other means used to control the flow of air must be adequate to prevent chilled air from entering the furnace and, if manually operated, must be equipped with means to prevent operation of either unit unless the damper is in the full heat or cool position.
When the furnace is installed without a cooling coil, it is recommended that a removable access panel be provided in the outlet air duct. This opening shall be accessible when the furnace is installed and shall be of such a size that the heat exchanger can be viewed for visual light inspection or such that a sampling probe can be inserted into the airstream. The access panel must be made to prevent air leaks when the furnace is in operation.
When the furnace is heating, the temperature of the return air entering the furnace must be between 55°F and 100°F.
When a furnace is installed so that supply ducts carry air circulated by the furnace to areas outside the space containing the furnace, the return air shall also be handled by a duct sealed to the furnace casing and terminating outside the space containing the furnace.
FILTERS - READ THIS SECTION BEFORE INSTALLING THE RETURN AIR DUCTWORK
Filters must be used with this furnace. Discuss filter maintenance with the building owner. Filters do not ship with this furnace, but must be provided by the installer. Filters must comply with UL900 or CAN/ULCS111 standards. If the furnace is installed without filters, the warranty will be voided.
NOTE: An undersized opening will cause reduced airflow. The bottom return is set up as a knock out.
UPRIGHT INSTALLATIONS
Depending on the installation and/or customer preference, differing filter arrangements can be applied. Filters can be installed in the central return register or a side panel external filter rack kit (upflows), or the ductwork above a counterflow furnace. As an alternative, a media air filter or electronic air cleaner can be used as the requested filter. The following figures show possible filter locations.
CIRCULATION AIR FILTERS
One of the most common causes of a problem in a forced air heating system is a blocked or dirty filter. Circulating air filters must be inspected monthly for dirt accumulation and replaced if necessary. Failure to maintain clean filters can cause premature heat exchanger failure.
A new home may require more frequent replacement until all construction dust and dirt is removed. Circulating air filters are to be installed in the return air duct external to the furnace cabinet.
MINIMUM FILTER SIZES
FURNACE INPUT | FILTER SIZE | TYPE |
45M | 160 in2 | permanent |
68M | 241 in2 | permanent |
90M | 320 in2 | permanent |
115M | 400 in2 | permanent |
135M | 370 in2 | permanent |
45M | 320 in2 | disposable |
68M | 483 in2 | disposable |
90M | 640 in2 | disposable |
115M | 800 in2 | disposable |
135M | 738 in2 | disposable |
PERMANENT NOMINAL 600 C.F.M.
DISPOSABLE NOMINAL 300 C.F.M.
HORIZONTAL INSTALLATIONS
Filters must be installed in either the central return register or in the return air duct work.
XI. SEQUENCE OF OPERATION
(INTEGRATED IGNITION CONTROL)
Refer to Timing Charts for sequencing.
POWER UP
1.115 VAC power applied to furnace.
2.Integrated ignition control performs internal checks.
3.Integrated ignition LED will light.
4.Integrated ignition control monitors safety circuits continuously.
5.Furnace awaits call from thermostat.
