Installation & Maintenance Manual Owner's manual

ManualsBrandsKees ManualsHoodsIFG (INDIRECT FIRED GAS) MAKE-UP AIR UNITS - Duct Furnace

INSTALLATION AND SERVICE MANUAL

OUTDOOR ROOFTOP GAS-FIRED DUCT FURNACE

(NATURAL OR POWER VENTED)

(S) RISM-9

J30-05380A

ATTENTION: READ THIS MANUAL AND ALL LABELS ATTACHED TO THE UNIT CAREFULLY

BEFORE ATTEMPTING TO INSTALL, OPERATE OR SERVICE THESE UNITS! CHECK UNIT DATA

PLATE FOR TYPE OF GAS AND ELECTRICAL SPECIFICATIONS AND MAKE CERTAIN THAT THESE

AGREE WITH THOSE AT POINT OF INSTALLATION. RECORD THE UNIT MODEL AND SERIAL No.(s)

IN THE SPACE PROVIDED. RETAIN FOR FUTURE REFERENCE.

Model No. Serial No.

FOR YOUR SAFETY

The use and storage of gasoline or other flammable vapors and liquids in open

containers in the vicinity of this appliance is hazardous.

INSTALLER'S RESPONSIBILITY

Installer Please Note: This equipment has been test fired and inspected. It has been shipped

free from defects from our factory. However, during shipment and installation, problems such as

loose wires, leaks or loose fasteners may occur. It is the installer's responsibility to inspect

and correct any problems that may be found.

SAVE THIS MANUAL

These units are certified by CSA International for operation on either natural or propane gas.

Read this manual and all labels attached to the unit carefully before attempting to install, operate or

service the following unit models:*

Outdoor Rooftop Duct Furnaces: QV(RT/PV)- (100, 150, 200, 250, 300, 350, 400) (H)(M)

(RT = Natural Vent; PV = Power Vent)

*Look in the direction of the unit air flow to determine whether the unit is right or left-hand accessible.

FOR YOUR SAFETY

If you smell gas:

1. Don’t touch electrical switches.

2. Extinguish any open flame.

3. Immediately call your gas supplier.

Improper installation, adjustment, alteration, service or maintenance can

cause property damage, injury or death. Read the installation, operating and

maintenance instructions thoroughly before installing or servicing this equipment.

Install, operate and maintain unit in accordance with manufacturer's

instructions to avoid exposure to fuel substances or substances from incomplete

combustion which can cause death or serious illness. The state of California has

determined that these substances may cause cancer, birth defects, or other

reproductive harm.

http://www.mestek.com

260 NORTH ELM ST., WESTFIELD, MA 01085

TEL: (413) 564-5540 FAX: (413) 562-5311

HVAC PRODUCTS

Summary of content (28 pages)

PAGE 1
(S) RISM-9 J30-05380A INSTALLATION AND SERVICE MANUAL OUTDOOR ROOFTOP GAS-FIRED DUCT FURNACE (NATURAL OR POWER VENTED) ATTENTION: READ THIS MANUAL AND ALL LABELS ATTACHED TO THE UNIT CAREFULLY BEFORE ATTEMPTING TO INSTALL, OPERATE OR SERVICE THESE UNITS! CHECK UNIT DATA PLATE FOR TYPE OF GAS AND ELECTRICAL SPECIFICATIONS AND MAKE CERTAIN THAT THESE AGREE WITH THOSE AT POINT OF INSTALLATION. RECORD THE UNIT MODEL AND SERIAL No.(s) IN THE SPACE PROVIDED. RETAIN FOR FUTURE REFERENCE. Model No. Serial No.
PAGE 2
tracks, and push up into the top lip; swing and lower the panel in place until it engages with the bottom panel. Turn the screwhead on each latch clockwise. The screw must turn freely one quarter turn before resistance is felt in order for the lock to engage. If the latch does not hold, turn the screw counter-clockwise several turns and repeat the above procedure. Also refer to Figures 8Aa, 8b and 8c. for more specifications. TABLE OF CONTENTS RECEIVING/PRE-INSTALLATION INSTRUCTIONS .......................
PAGE 3
GENERAL SAFETY INFORMATION Roofcurb kits for rooftop gas heating units are shipped knocked down. A curb kit contains (insulated) curb rails, hardware, sealant, self-adhering rubber gasketing, and installation instructions. Roof insulation, cant strips, flashing, roof felts, caulking and nails must be furnished by the installer. See separate curb specifications from manufacturer.
PAGE 4
SPECIFICATIONS Figure 1 - Standard Natural Vented Outdoor Duct Furnace 1" (25) Typ. A 26" (660) C (Typ.) Vent Cap Is Shipped In Separate Carton Gas Connection CL D 19" (483) Opening 1-1/8" (29) Typ. Duct Flange Electrical Connections 39" (991) 10-1/8" (257) 5-1/16" (129) 5/8" (16) Typ. Anchor Hole Location DFR3538A TFR3779A B Opening Typ. 8-3/4" (222) 31-1/4" (794) * F 4" (102) 13/16" (21) Typ.
PAGE 5
Chart 2 - Performance and Specification Data CAPACITY MBH 100 NATURAL VENT 150 200 250 300 350 400 100 POWER VENT 150 200 250 300 350 400 ** 100H NATURAL VENT 150H 200H 250H 300H 350H 400H ** 100H 150H POWER VENT 200H 250H 300H 350H 400H INPUT RATING BTU/Hr (kW) OUTPUT RATING BTU/Hr (kW) 100,000 (29.3) 150,000 (43.9) 200,000 (58.6) 250,000 (73.2) 300,000 (87.8) 350,000 (102.5) 400,000 (117.1) 80,000 (23.4) 118,500 (34.7) 158,000 (46.3) 197,500 (57.8) 237,000 (69.4) 276,500 (81.
PAGE 6
PERFORMANCE DATA CURVES Figure 3 - High Temperature Rise Duct Furnaces — 30-90 F° (17-50 C°) Pressure drop through the heat exchanger is based on the CFM throughput. The desired data is obtained in the following manner: 1. Select heater size based on heat loss of the building to be heated. 2. Select temperature rise desired. 3. Based on temperature rise, the horizontal line intersects heater temperature vs. CFM curve. 4. Follow vertical line down to select CFM. 5.
PAGE 7
BYPASS SIZING INFORMATION (BUILT ON THE JOB – NOT FURNISHED BY FACTORY) On occassion when a duct furnace is incorporated in an air handling system, it may be desirable to handle a total of more CFM than the duct furnace will pass at a given static pressure drop and temperature rise. Therefore, it is necessary to arrange to bypass the additional CFM required. The size of the bypass duct can be determined by referring to the chart.
PAGE 8
INSTALLATION Open all disconnect switches and secure in that position before installing unit. Failure to do so may result in personal injury or death from electrical shock. Installation must conform with local building codes, or in the absence of local codes, with the National Fuel Gas Code ANSI Z223.1-1999, or the latest edition. A heat loss study and a complete layout of the system should be made first.
PAGE 9
VENTING All venting installations shall be in accordance with the latest edition of “Part 7, Venting of Equipment of the National Fuel Gas Code, ANSI Z223.1-1999, or applicable provisions of local building codes”. Natural venting models are equipped with a vent cap designed for natural venting. Air for combustion enters at the base of the vent through a protective grille, and the design of the vent cap is such that the products of combustion are discharged at the upper section of the cap.
PAGE 10
DUCT SPECIFICATIONS Ductwork which is outdoors must be insulated and sealed to prevent water from entering either furnace or building through the duct. Do not alter the flange connection for the duct attachment; air may bypass and cause combustion problems. Be sure to properly seal to avoid any air leakage (refer to Figures 1 and 2). Ductwork connected to duct furnaces should have removable access panels on both the upstream and downstream sides of the unit.
PAGE 11
GAS CONNECTIONS (continued) For the most satisfactory piping installation, the following procedure should be followed. Make piping layout of the whole installation and calculate the cubic feet of gas that each supply pipe will carry. See piping example below. NOTICE: If more than one gas duct furnace is to be served by the same piping arrangement, the total cu. ft./hr. input and length of pipe must be considered.
PAGE 12
Chart 3 GAS PIPE SIZE Maximum Capacity of Pipe in Cubic Feet of Gas per Hour for Gas Pressures of 0.5 psig (3.5 kPa) or Less, and a Pressure Drop of 0.5 Inch Water Column (124.4 Pa) (Based on a 0.60 Specific Gravity Gas) Nominal Iron Internal Pipe Size Dia. in. 1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 4 Length of Pipe, ft. (Meters) in. 10 20 30 40 (mm) (3.0) (6.1) (9.1) (12.2) 50 60 (15.2) (18.3) 70 80 90 100 125 150 175 200 (21.3) (24.4) (27.4) (30.5) (38.1) (45.7) (53.3) (61.0) 0.
PAGE 13
OPERATION GENERAL All units are equipped with intermittent pilot ignition systems. This system is 100% pilot burner shut off. See Figure 11 for burner/gas controls. The pilot is lit and extinguished during every cycle of operation. There is no burning standing pilot. On natural gas units, the ignitor will continue to spark and pilot gas will continue to flow until the pilot flame is proven. LP (propane) gas units are equipped with 100% lockout.
PAGE 14
OPERATION continued Chart 4 - Gas Supply Pressure Heating Value Manifold Pressure Minimum Supply Pressure Single Stage Application Two Stage Application Natural Gas 1075 Btu/Ft3 (40.1 MJ/m3) 3.5 in. W.C. (0.87 kPa) Propane Gas 2500 Btu/Ft3 (93.1 MJ/m3) 10.0 in. W.C. (2.49 kPa) 5.0 in. W.C. (1.24 kPa) 6.5 in. W.C. (1.62 kPa) 11.0 in. W.C (2.74 kPa) 11.5 in. W.C. (2.86 kPa) CONTROLS Electronic modulating gas firing is available from the factory on natural and propane gas units.
PAGE 15
GAS CONTROLS continued TWO-STAGE CONTROL Optional two-stage control is provided with a two-stage gas valve capable of firing at 100% and 40% of rated input. Ignition at a low fire (40% of the unit's rated input) and the unit is typically controlled by a voltage two-stage thermostat. With power applied to the unit, this system operates in the following manner: 1. The first stage of the thermostat call for heat. 2. The pilot valve opens. 3. The ignitor sparks continuously to ignite the pilot. 4.
PAGE 16
GAS CONTROLS continued With power applied to the unit, this system operates in the following manner: 1. The thermostat calls for heat. NOTICE: If a thermostat is not supplied, steps 2 through 5 will be constant as long as power is applied to the unit 2. The pilot valve opens. 3. The pilot sparks continuously to ignite the pilot. 4. The sensor proves pilot ignition and shuts off the ignitor. NOTICE: The unit firing is controlled by the hydraulic sensing bulb on the mechanical valve.
PAGE 17
AIR DISTRIBUTION Two basic air control systems are used to deliver conditioned air to the occupied space: “constant” fan operation and “intermittent” fan operation. INTERMITTENT FAN OPERATION This air control system is available on duct furnaces when the fan time delay relay is ordered (optional). The thermostat turns the gas on whenever the temperature drops below the thermostat setting. The fan time delay relay allows the unit to fire for a period of 60 seconds before fan operation.
PAGE 18
LIGHTING continued 2. Turn on electrical power. The unit should now be under the control of the thermostat. 3. Turn the thermostat to the high heat reading to see if the pilot and main burner ignite. 4. Turn the thermostat to the lowest setting to interrupt power to the ignition system to determine that both the pilot burner and main burner are extinguished. 5. Set the thermostat at the desired setting for normal operation. For complete shutdown: 1. Turn the main and pilot valves to the OFF position. 2.
PAGE 19
GAS INPUT ADJUSTMENT When shipped from the factory, all gas fired units are equipped for the average BTU of the gas stamped on the rating plate. Since the BTU content of gases varies in many localities, the input must be checked after installation of the unit. If the unit is overfired, the overheating will substantially shorten the life of the heat exchanger. Never exceed the input on the rating plate. The input may be checked by either the meter method or the pressure of the gas in the manifold.
PAGE 20
START-UP (continued) FINAL CHECKOUT Run the unit sequentially through its stages of heating. One proper unit operation is verified, perform these final steps: 1. Inspect the unit for debris and/or misplaced tools and hardware. 2. Disable air handling blower. Fire unit and confirm that high limit switch shuts gas off within approximately 5 minutes. Re-enable air handling blower. 3. Be sure all gas valves and controls are in the operating position if the unit will be operating immediately 4.
PAGE 21
Figure 13 - Natural Vent Duct Furance Figure 14 - Power Vent Duct Furnace – 21 –
PAGE 22
Chart 6 - Trouble Shooting SYMPTOMS A. Gas odor. POSSIBLE CAUSES 1. Shut off gas supply immediately. 2. Blocked heat exchanger. 1. Inspect all gas piping and repair. 2. Clean heat exchanger. 3. Drafts around heater. 3. Eliminate Drafts. Refer to installation. 4. See installation. 4. Negative pressure in the building. 5. Blocked draft hood/flue collector. B. Delayed ignition. 1. Excessive primary air. 2. Main burner ports clogged near pilot. 3. Pressure regulator set too low. 4.
PAGE 23
Chart 6 - Trouble Shooting continued SYMPTOMS 8. Defective transformer. 9. Loose wiring. 10. Defective ignition control. E. Flame lifting from burner ports. CORRECTIVE ACTION POSSIBLE CAUSES 1. Pressure regulator set too high. 2. Defective regulator. 3. Burner orifice too large. 8. Be sure 115 volts is supplied to the transformer primary then check for 24 volts at secondary terminal before replacing. 9. Check and tighten all wiring connections. 10. Replace. 1. Reset manifold pressure.
PAGE 24
Chart 6 - Trouble Shooting continued SYMPTOMS J. Floating flame. POSSIBLE CAUSES 1. Blocked heat exchanger. 2. Insufficient combustion air. 3. Blocked venting. 4. Air leak into combined chamber, draft hood, or flue collector. K. Burner won't turn off. 1. Poor thermostat location. 2. Defective thermostat. 3. Improper thermostat or transformer. 4. Short circuit. 5. Defective or sticking gas valve. L. Rapid burner cycling. 1. Clean heat exchanger. 2. Clean combustion air inlet openings in bottom panel.
PAGE 25
Chart 6 - Trouble Shooting continued SYMPTOMS N. Too much heat. CORRECTIVE ACTION POSSIBLE CAUSES 1. Thermostat malfunction. 2. Heater runs continuously. a. Improper thermostat or transformer wiring at gas valve. b. Short circuit. 1. Replace thermostat. 2. a. Check wiring per diagrams. b. Check operation at valve. Look for short and correct (such as staples piercing thermostat wiring). c. Replace gas valve. c. Defective or sticking gas valve. d. Excessive gas supply pressure. *P.
PAGE 26
How to order Replacement Parts Please provide the following information to your local representative: • Models Number • Serial Number (if any) • Part Description and Number as shown in Replacement Parts Literature If further assistance is needed, please contact the manufacturer's customer service department. SERVICE NOTE Due to the many configurations, options and voltage characteristics available on Outdoor Duct Furnaces, the information provided in their manual is somewhat general in its context.
PAGE 27
GAS EQUIPMENT START-UP Customer ____________________________________ Job Name & Number _________________________ PRE-INSPECTION INFORMATION With power and gas off. Type of Equip: Rooftop DF Serial Number _________________________ Model Number __________________________ Name Plate Voltage: _____________ Name Plate Amperage: _____________ Type of Gas: Natural Tank Capacity _______ lbs.
PAGE 28
HVAC PRODUCTS 260 NORTH ELM ST., WESTFIELD, MA 01085 TEL: (413) 564-5540 FAX: (413) 562-5311 http://www.mestek.