I have yet to find what the difference is between the
Four Seasons 74827 and the 74828 heat control valves.
How did you mount your valve Harold? I don't see a mounting
bracket. Normally they are simply installed in one of
the 5/8" heater hose lines.
Denny Graham
Sandwich, IL
Denny,
Per 4-Season "The difference between 74827 and 74828 is the internal valve, it's clocked differently. The 74827 flows to the right and 74828 flows to the left".
Mike B
