Greenheck Fan VSU manual Maintenance - Fall, Bearings, Start-Up, High Limit, Burner

Bearings

The bearings for Greenheck fans are carefully selected to match the maximum load and operating conditions of the specific class, arrangement and fan size. The instructions provided in this manual and those provided by the bearing manufacturer will minimize any bearing problems.

IMPORTANT

Lubricate bearings prior to periods of extended shutdowns or storage and rotate shaft monthly to aid in corrosion prevention. If the fan is stored more than three months, purge the bearings with new grease prior to start-up.

Recommended Bearing Lubrication Schedule (in Months*)

Fan		Bearing Bore Size (inches)
RPM	1⁄2 - 1	11⁄8 - 11⁄2	15⁄8 - 17⁄8	115⁄16 - 23⁄16	27⁄16 - 3
750	6	5	4	3	3

*Suggested initial greasing interval is based on 12 hour per day operation and 150°F maximum housing temperature. For continuous (24 hour) operation, decrease greasing interval by 50%

•If extended grease lines are present, relubricate while in operation, only without endangering personnel.

•For ball bearings (operating) relubricate until clean grease is seen purging at the seals. Be sure not to unseat the seal by over lubricating.

•For ball bearings (idle) add 1-2 shots of grease up to

2 inch bore size, and 4-5 shots above 2 inch bore sizes with a hand grease gun.

•For roller bearings add 4 shots of grease up to 2 inch bore size, and 8 shots for 2-5 inch bore size with a hand grease gun.

•Adjust relubrication frequency based on condition of purged grease.

•A high quality lithium based grease conforming to NLGI

Grade 2 consistency, such as those listed here:

Mobil 532	Texaco Multifak #2	B Shell Alavania #2
Mobilux #2	Texaco Premium #2	Exxon Unirex #2

Maintenance - Fall

Start-Up

Repeat the Blower Start-Up Step #5 and Direct Gas Start- Up Steps #1 through #4. 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 clear. If any burner ports are plugged (even partially), clear them with a piece of wire or another appropriate tool.

Replace or tighten any loose or missing fasteners on the mixing plates. Always use zinc plated or stainless steel fasteners.

Inspect and clean the flame and spark rod. Occasional replacement of the flame rod and spark rod may be necessary to ensure optimum unit performance.

warning

Do not enlarge burner ports when clearing a blockage, performance could be affected.

note

Flame rods can last many years, but because of thermal expansion of the porcelain, flame rods can fail over time.

Model VSU Make-Up Air 19

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