Hydrotherm -Series ® Gas-fired direct vent Cast iron boilers Model KN-20 only Field assembly instructions Also read and follow: KN Series Gas Boiler Installation & Operating Instructions and KN HeatNet Control Manual This manual is intended only for use by a qualified heating installer/technician. Read and follow this manual, all supplements and re- lated instructional information provided with the boiler. Install, start and service the boiler only in the sequence and methods given in this manual and the documents listed above. Failure to do so can result in severe personal injury, death or substantial property damage. Do not use the boiler during construction.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Contents and information Read before beginning the installation Hazard icons Boiler ratings and specifications You will find the following icons throughout this manual. Installation site preparation (English/French) Prepare the boiler The WARNING icon indicates Water piping a hazard that can cause severe...
KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Read before proceeding Customer service and technical support Direct all questions to your HydroTherm distributor or contact the HydroTherm Customer Service Department at: 260 North Elm Street Westfield, MA 01085.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Components and special tools required Special equipment/materials required for assembly 1. One quart 30-wt motor oil 5. Two 18-inch pipe wrenches 8. Standard hand tools, wire, nuts, electrical hand tools 2.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 1 Place 4x6 boards on base 1. Remove base from skid. 2. Place a 4x6 board (supplied) against Ignore the palette under the each side as a runner shown. boiler in the manual images 3. Space runner boards with about even — it is left in place during amounts off of each end of the base.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 5 Prepare section for baffle Use of an approved dust 1. Spray cast iron heat pin section liber- respirator is strongly recom- ally with spray adhesive supplied with mended when handling the the boiler. insulating components of the 2. Avoid spraying on the nipple port boiler.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 8 Push nipple lubricant Rubber gloves are recom- 1. In a disposable container, mix some mended for this procedure. 30-wt motor oil with some of the Hercules Pro Dope supplied with the boiler. 2.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 12 Seat the push nipples 1. Place a 2x4 board across the nipple and strike firmly with a mallet. 2. Do this with several strokes, just so the push nipple is firmly started.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 16 Install baffle Do not use baffles if they 1. Before adding additional sections, have been broken, cracked, install a baffle in the flueway as in folded or frayed. Obtain re- Step 5, page 6 and Step 6, page 6. placements before proceed- 2.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 20 Bolt boiler to base Before bolting the boiler to 1. Install a bolt, wedge, washer and nut the base, knock the two 4x6 on side of the front section as done in boards out from under the Step 4, page 5. block. If necessary, loosen the 2.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 24 Install condensate drain connector 1. The condensate drain connector con- The condensate drain pan sists of a plate, O-ring and strainer. is shown here without the inspection plate and gasket 2. Assemble the three parts as shown. installed, to be installed in 3.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 27 Install combustion cham- The combustion chamber 1. Insert the chamber into the top of the material is fragile, and can be section assembly as shown. cracked or gouged with in- 2. Position the chamber with the correct handling. HANDLE ROUND hole toward the front and the CAREFULLY! DO NOT SQUARE hole to the rear.
KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 30 Burner and manifold REMOVE THE PILOT 1. This illustration shows the manifold ORIFICE ASSEMBLY (left) and the burner (right). before proceeding. The pilot 2. Orient the burner as shown, with the orifice assembly (shown in double set of bolt notches on the Step 37, page 15) is factory- same side as the blower flange of the...
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 33 Install the burner 1. Place the burner on top of the section assembly as shown. 2. The PILOT TUBE must be at the REAR of the boiler. Step 34 Install burner bolts 1.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 37 Install pilot assembly 4. After ensuring the pilot tube is 1. Use a flashlight to look down through aligned properly, insert the pilot the pilot mounting hole at the top orifice assembly as shown.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 40 Apply jacket front insula- tion 1. Press jacket front insulation against Leather gloves are recom- the back of the front panel. mended when handling sheet metal components. They will reduce the possibility of cuts from sheet metal edges. Step 41 Mounting hole alignment 1.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 43 Apply jacket rear insula- tion 1. Press jacket rear insulation against the back of the rear panel. Use of an approved dust respirator is strongly recom- mended when handling the insulating components of the boiler. Step 44 Install jacket rear panel The jacket rear panel is sup- 1.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 45 Install flue adapter Make sure the flue adapter 1. Apply silicone RTV to the flue adapter condensate nipple is located mounting boss. at the BOTTOM when in- 2. Position the flue adapter on the boss stalled. and insert the four mounting bolts. The condensate nipple must be Rubber gloves are recom- pointed DOWN.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 48 Install the ignition elec- trode assembly 1. Check the distance from the ignition Check/adjust the igniter electrode plate to the front end of the electrode positioning before ignition electrode ceramics. It must installing. They are not fac- be 1½...
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 51 Mount the control panel The control panel mounts on 1. BX conduit fitting — Hold the control the mounting clip at the top panel close enough to the jacket of the jacket front panel. The front panel to allow inserting the conduit fitting and the sensor conduit fitting through the back of hose must be routed through...
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 54 Mount the gas train 1. Attach the gas train to the front of the boiler using the bolts supplied. Step 55 Re-attach gas line nipple brackets 1.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 58 Move the air box/blower assembly into position 1. This procedure requires two people. 2. Move the air box/blower assembly into position. 3. Guide the gas line into the grommet- fitteded opening in the bottom of the air box.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 62 Install gas valve by-pass line 1. Connect an aluminum tube (sup- De-burr the aluminum tub- plied with boiler, but cut to length ing after cutting to ensure the during installation) from the gas valve ends are not obstructed.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 66 Install jacket right side panel 1. Secure the jacket right side panel in Leather gloves are recom- place using the screws provided. mended when handling sheet metal components. They will 2. Position the pilot gas tubing in the reduce the possibility of cuts slot located in the top right end of from sheet metal edges.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 70 Route plastic sense line through jacket rear 1. Disconnect the rear conduit junction box before proceeding. 2. Guide the plastic sense line through the grommeted hole in the jacket rear panel.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 74 Connect wires to air box components 1. Connect the wires from the air pres- See the wiring diagrams, sure switch and relief valve switch to Figure 1, page 28 and Fig- the control panel. for detailed ure 2, page 30 information.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Step 78 Install the air box cover The air box cover MUST be 1. Attach the air box cover using the in place during boiler opera- screws provided. tion. Step 79 Install the air gas train shroud 1.
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Figure 1 Schematic wiring diagram (numbered bullets show locations of wiring field connections (all wires color coded and numbered) P/N 42-9551...
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Figure 1 (Continued) P/N 42-9551...
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Figure 2 Ladder wiring diagram P/N 42-9551...
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions Figure 2 (Continued) P/N 42-9551...
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KN Series Gas-fired direct vent cast iron boilers – Field assembly instructions P/N 42-9551...
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