Troubleshooting
Tech Support: 1-800-4BIORAD • 1-800-424-6723 • www.bio-rad.com 10-11
Problem
Cause
Action
No reaction products
obtained.
Wrong protocol used.
Re-run reaction using correct
protocol.
Protocol contains a wrong value.
Use List utility to check protocol’s
temperature control method, tem-
peratures, and times.
Reaction component omitted from
mixture.
Check reaction assembly protocol,
ensuring that mixture contains
appropriate components in correct
concentrations.
Denaturation temperature too low.
Use 92°C for denaturation. Only
rarely are temps higher than 94°C
required, however.
Annealing temperature too high for
primers.
Check for appropriate annealing
temperatures of primers, using
available computer programs or
empirical testing.
Wrong temperature control method
used.
Use List utility to check tempera-
ture control method for protocol;
change if needed.
Probe failed, causing machine to run
protocol under calculated control.
Check screen for probe failure error
message. Probe may need servicing
or replacing. Call Bio-Rad
Laboratories or your local distributor.
Probe not filled with correct
amount of oil.
Fill probe tube with correct amount
of oil (see p. 4-12).
Reaction mix contains an inhibitor
(e.g., heme from blood).
Test a complete reaction mix,
minus sample, with a control
template and primer set.
Reaction vessels not making good
thermal contact with sample block.
Use only high-quality tubes/plates
that fit block snugly. Ensure that
wells are free of foreign materials
that would interfere with tube/plate
seaing.
