GSI Outdoors PNEG-630 - Manual (Page 63)

Portable Dryer Troubleshooting
62
soon as the burner is turned on. The
vaporizer must be adjusted to solve this
problem.
Using J5-11 as the negative test point for all voltage
tests, check for 12 volts DC using the following termi-
nals to help diagnose the problem:
Fan #1-J1-5 Fan #2-J1-6
Fan #3-J2-5 Fan #4-J2-6
Fan #5-J3-5 Fan #6-J3-6
Remember that each of these input terminals is part of
the main safety circuit of the dryer, and each must
have 12 volts DC on it before the dryer will operate.
Vapor High Limit Hints
1. Anytime you adjust the Vapor High you
should wait and be sure that the pipe train
temperature stays constant. It may slowly
allow the pipe train to get hotter or colder
the longer the dryer runs.
2. If a dryer is shutting down constantly from
a Vapor High Limit, it may also be caused
from a gas line that is exposed to direct
sunlight. If the fuel line to the dryer is
exposed to direct sunlight, the liquid in
the line will start to vaporize before it
even gets to the dryer. Then, when it runs
through the vaporizer it gets too hot and
causes a shutdown (no matter where you
try and adjust the vaporizer). This prob-
lem can be helped by insulating the gas
line from outside heat.
3. In extreme cases the vaporizer may have
to be changed before it will run the proper
temperature. Example: If a dryer has a
burner with a three wrap vaporizer and the
dryer is located in the southern United
States, you may have problems adjusting
thevaporizer far enough from the flame.
In this case, you may have to install a two
wrap vaporizer.
Troubleshooting Tips
The two wrap has less surface area and it
will not heat the LP quite as much. This
may also be true in colder climates where a
two wrap will not heat up enough. In this
case, the pipe train may develop frost or
even freeze the solenoids open.
4. The Vapor High Limit is an automatic reset
safety device. It will reset itself as soon as
its temperature drops below 190° F. Be-
cause the pipe train of the burner cools
down rapidly when there is a dryer shut
down, the Vapor High Limit will generally
be cool before the operator gets back to the
dryer. As soon as he hits the stop button to
reset the computer, it comes back up to
normal operation. It appears that the dryer
is shutting down for no apparent reason.
Usually if this happens the dryer will shut
down again a short while after restarting the
dryer.
5. If the LP tank feeding the dryer is getting
very low on fuel, it can also cause the
dryer to shutdown on a Vapor High Limit.
Before adjusting the vaporizer always
check the fuel level in the customers tank.
If the fuel pressure is very low, try suggest
ing that the tank be refilled. Usually this
will solve the problem.