Changing the Lucks M Series Heat Exchanger Version 2.0 There are Four (4) main steps to removing and replacing the heat exchanger in a Lucks M Series oven. 1) If at all possible have the oven in fully operational condition before starting the removal of the burner. This will assure you that all was functionally OK before and should be OK afterwards. 2) Removal of the old heat exchanger and repair of any damage you find caused by the defective heat exchanger before replacing with the new one. 3) Installation of the new heat exchanger and fire-off of the oven once again. 4) Performing the burner combustion adjustment and performance procedures, record the results and returning the form to for the warranty validation. Step 1 Oven functionality testing and repair You will save yourself hours of grief if you can start with a working oven except for the burn quality or heat exchanger performance. All electrical systems should be functional, NOW is the time to test them and make any repairs. If parts have been removed or are missing now is the time to inform your management as they may wish the install to hold for a later date or need additional approval to proceed. Step 2 Removal of the old heat exchanger 15306 E. Wellesley Ave. Spokane Valley, WA 99216 USA Phone: 206-274-5282 / 877-749-5739 Fax: 509-928-3252 www.baketechpros.com Start by being safe! Shut off the gas at the line valve and kill the power at the breakers. Note how the burner is wired and mounted. Look at the gas lines Now remove the burner completely leaving the gas valve in place. Page 1 of 10 Copyright 2008-2009. Revised 08/27/09
Page 2 of 10 Copyright 2008-2009. Revised 08/27/09 Remove the left inner wall (Perf Sheet) and save the screws. Set this large piece of sheet metal aside in a safe place, it will be reused. Remove the sheet metal wall cover, that was behind the burner, and the insulation, save the screws, sheet metal and all of the insulation as they will be reused. Twist UP the outside flange of the centering slot to enable much easier removal and installation of the heat exchanger. Spray the heat exchanger leveling bolt threads with WD 40 or equivalent.
Page 3 of 10 Copyright 2008-2009. Revised 08/27/09 Remove the muffler flange bolts. Remove the nuts holding the heat exchanger muffler flange. CAUTION! The weight of the heat exchanger is now supported by the burner muffler insert flange. With the heat exchanger supported, remove the muffler flange. It should now be possible to remove the heat exchanger. It is HEAVY! Use a helper! Loosen the upper sealing ring flange bolts, swing the back end out away from the leveling mount, pull the heat exchanger out at the bottom, and then lower.
Page 4 of 10 Copyright 2008-2009. Revised 08/27/09 CLEAN UP TIME! Now is the time to clean up the mess left in the drain pan and on the rebar. Prevent a recall due to a plugged drain pan! Vacuum it out! IMPORTANT! Remove any baffles mounted to the Perf Sheet, left wall, back or front walls. Fill any holes left in the walls with the old screws and some silicone sealant. Now onto the installation of the NEW heat exchanger and the air control baffles.
Page 5 of 10 Copyright 2008-2009. The new heat exchanger is assembled IN PLACE with gaskets provided to seal the connections. DO NOT use any silicone sealant on the heat exchanger or its flanges. Revised 08/27/09
Page 6 of 10 Copyright 2008-2009. Revised 08/27/09 Lift the combustion section into place with the leveling flange sitting on the leveling nut. It will ease installation if you enlarge these oven wall flange holes by about ¼ inch. Using the flat fiberglass gasket supplied, glue one layer around the back side of the muffler flange with silicone sealant. Place the white Fiberfrax gasket in-between the heat exchanger flange and the oven wall, insert the muffler flange back into the heat exchanger from the burner side. Re-using the saved bolts hand tighten all four bolts in place, DO NOT TIGHTEN at this time.
Page 7 of 10 Copyright 2008-2009. Revised 08/27/09 Loosen the upper sealing flange bolts and fix / reposition the sealing gasket. Be sure the shipping nuts have been removed from the connecting flange bolts (do NOT reuse these nuts), place the gasket in place. With a helper lift the tube section up and slide the exhaust box into the upper sealing flange, Lift the tube section up as far as it will go and settle its flange over the bolts. Using the supplied nuts and washers in the parts kits, fully tighten down the nuts until the split washers are flat. Level the heat exchanger with the leveling bolt and bend the centering flange back into place.
Page 8 of 10 Copyright 2008-2009. Revised 08/27/09 Tighten the burner muffler flange bolts and re-insulate the wall then cover with the sheet metal plate reusing the old TEK screws. You can re-install the burner at this time or wait until later. Assemble the air control baffles. You will need Two (2) long and Two (2) short main pieces and Two (2) stub pieces. Using the supplied TEK screws assemble One (1) Stub piece to a long and a short main section as shown. Longer baffles Shorter baffles
Page 9 of 10 Copyright 2008-2009. Revised 08/27/09 Secure the baffles to the walls as shown using the supplied TEK screws. Approximately centered in-between the heat exchanger tubes and reasonably level. Approximately Three (3) inches from the heat exchanger tubes and level. Tighten the upper sealing flange nuts and verify the seal.
Page 10 of 10 Copyright 2008-2009. Revised 08/27/09 Check the oven carefully for lost tools. You will be SO sorry if you leave your level on the tubes when you fire the oven!! Reinstall the Perf sheet, clean up the inside of the oven and install the burner if you have not already done so. Now is the time to CLEAN the burner combustion air fan This is a very important step, don t pass it by! The smallest amount of dirt has a HUGE effect on the performance. Ok, you re almost done. Turn the power back on but leave the gas off. Fire the burner and verify the combustion fan comes on, the green, blue then red burner lights come one Once you re sure everything is ok move on to the FIRE OFF procedure