LAARS Mighty Therm LO-NOx VW (Sizes 250/400) - Installation, Operation and Maintenance Instructions - Manual (Page 4)

LAARS Heating Systems Page 4
for outdoor installations. In special circumstances an
outdoor vent cap may be required. Check the part
number on the rating plate.
The VW, PW heaters are design certified for
indoor installation when equipped with a special
drafthood, which must be installed without
modification. The part number for the drafthood is on
the heater rating plate. Follow this procedure to make
the conversion:
1. Remove the top plate, stamped "HOT", by
slipping a fine-blade screwdriver into the slot and
prying it up (see Figure 2).
2. Remove the top by removing all eight screws
connecting it to the jacket (see Figure 3).
3. Remove the rainguard assembly (see Figure 4).
4. Remove the two screws securing the left
vestibule cover (see Figure 5). The cover can be
discarded.
5. Remove the vent cap or drafthood and
accessories from the carton.
6. Place transition plate (with 14" long side)
securely on top of flue collector so flue gases will
not leak (see Figure 6).
7. Remove back portion of rainguard (see Figure 7).
8. Re-install the rainguard (see Figure 8).
9. Replace heater top and all eight screws (see
Figure 9).
10. Slide the adapter plate up over the bottom of the
stack extension. Fit the stack extension, of the
drafthood or the vent cap, on top of the collar of
the flue transition plate (see Figures 10 and 11).
11. Seat the adapter plate on the top assembly, and
secure it with screws supplied in the kit (see
Figure 12).
12. Attach the clips to the adapter plate by securing
the slotted side of the clips with the screws in the
kit (see Figure 13).
13. Use the holes in the clips as guides to drill three
1/8" dia. holes in the stack.
14. Secure the stack to the clips with the screws
supplied in the kit (see Figure 13).
15. Figure 14 shows a cross-section of the finished
installation.
16. Indoor models, size 250 only, require an adapter
cable (included with product). The cable connects
the blocked vent safety switch (BVSS) on the
bell of the external draft hood to the 6-position
Molex plug on the side of the unit (see Figure
15). Refer to instruction sheet included with
cable.
1.2 Warranty
Laars Heating Systems Mighty Therm heaters are
covered by a limited warranty. The owner should fill
out the warranty registration card and return it to Laars
Heating Systems.
All warranty claims must be made to an
authorized Laars Heating Systems representative or
directly to the factory. Claims must include the serial
number and model (this information can be found on
the rating plate), installation date, and name of the
installer. For specific warranty conditions refer to your
Limited Warranty.
Some accessory items are shipped in separate
packages. Verify receipt of all packages listed on the
packing slip. Inspect everything for damage
immediately upon delivery, and advise the carrier of
any shortages or damage. Any such claims should be
filed with the carrier. The carrier, not the shipper, is
responsible for shortages and damage to the shipment
whether visible or concealed.
SECTION 2.
Installation Instructions
2.1 General Information
WARNING
Improper installation or maintenance can cause
nausea or asphyxiation from carbon monoxide in
flue gases which could result in sever injury,
property damage or death. Follow the manufactur-
er’s maintenance schedule for the appliance. Follow
local regulations with respect to installation of
carbon monoxide (CO) detectors.
All gas-fired products require correct installation
to assure safe operation. The requirements for heaters
include the following:
1.
Field assembly of drafthood or vent cap (see
Section 2.2).
2. Appropriate site location clearances and flooring.
3. Sufficient combustion and ventilation air.
4. Adequate venting of combustion products.
5. Adequate water flow.
6. Properly sized gas meter and piping.
7. Proper electrical wiring.
This manual provides the information needed to
meet these requirements. Review all application and
installation procedures completely before continuing
the installation.
2.2 Field Assembly
The VW-PW heaters are shipped from the factory
with the top assembly in the low-profile configuration
OUT OF
PRODUCTION