Greenheck DGX Installation, Operation And Maintenance Manual page 41

Maintenance - Fall
Start-Up
Repeat the Blower Start-Up procedure #5 and Direct Gas Start-Up procedure #1, 2 and 3. This will ensure that
the gas and air are set properly before the heating season begins, and should lead to trouble free operation all
winter.
High Limit
The high limit switch may have tripped over the summer, it should be checked and reset if necessary.
Burner
Inspect the burner for accumulation of scales on both the upstream and downstream sides of the mixing plates.
Any scaling or foreign material should be removed with a wire brush.
Visually check that all holes in the mixing plates are
WARNING!
clear. If any burner ports are plugged (even partially),
Do not enlarge burner ports when clearing a
clear them with a piece of wire or another appropriate
blockage, performance could be affected.
tool.
Replace or tighten any loose or missing fasteners on the mixing plates. Always use zinc plated or stainless steel
fasteners.
NOTE!
Inspect and clean the flame and spark rod. Occasional
Flame rods can last many years, but because of
replacement of the flame rod and spark rod may be
thermal expansion of the porcelain, flame rods
necessary to ensure optimum unit performance.
can fail over time.
Flame Rod Spark Rod
Mixing Plate Holes Burner Ports
Figure 65. Burner
Evaporative Coolers
The water should be shut off and all the lines drained when the outside temperature drops below 45°F.
Remove drain plugs for the winter.
Clean all interior parts of any mineral deposits or foreign materials that may have built-up during the cooling
season.
Replace any worn or non-functioning parts.
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