Spirit CT850 Owner's Manual page 41

Treadmill will only achieve
approximately 7 mph but shows higher
speed on display
Tread-belt stops quickly/suddenly when
tether cord is pulled
Treadmill trips on board 15 amp circuit
Computer shuts off when console is
touched (on a cold day) while
walking/running
This indicates motor should be receiving power to operate.
Low AC voltage to treadmill. Do not use an extension cord. If
an extension cord is required it should be as short as possible
and heavy duty 16 gauge minimum. Low voltage. Contact an
electrician or your Spirit Fitness dealer. A minimum of 110 volt
AC current is required.
High belt/deck friction. See General Maintenance section
on cleaning the deck. If cleaning doesn't prevent this from
reoccurring, check to see if there is significant wear of the deck.
If so, the deck may need to be flipped if it is on its original side
High belt/deck friction. See General Maintenance. If cleaning
doesn't prevent this from reoccurring, check the amp draw of
the motor. If this is high and there are signs of significant wear of
the deck, it may need to be flipped if it is on its
original side
Treadmill may not be grounded. Static electricity is "crashing"
the computer. Refer to Grounding
Instructions on page 3.
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