Global 8550-RU, Operating Manual, Page: 27 / 61

Global Power Technologies SERVICE AND MAINTENANCE
302954 rev0 | Model 8550-RU Page 23 of 53
To perform the test:
1. Take a reading of the momentary open circuit as per the procedure in Section 5.9 – Power Unit
Testing.
2. Calculate the open circuit voltage (V
oc
) and internal resistance (R
INT
) of the Power Unit as
described in Section 5.9 – Power Unit Testing.

If the V
oc
is above 56 Volts and R
INT
is above 1.40 Ohms, the Power Unit is likely faulty. The
Power Unit may still be able to operate at reduced output. Consult Global Power
Technologies to determine the safe operating level for the Power Unit under your
conditions.

If the V
oc
is below 56 Volts and R
INT
is above 1.30 Ohms, the Cooling System is likely faulty,
see Section 5.3– Cooling System for further tests.

If the V
oc
is below 56 Volts and R
INT
is below 1.00 Ohms, the Burner or Fuel System is likely
not providing enough heating.
a) Perform the basic service outlined on Section 5.2,
b) Check and replace the fuel orifice as outlined on Section 5.4, and
c) Check the complete Burner System for obstructions and damage as outlined on Section
5.5 .
If after servicing and restarting, the Power Unit still does not come to Set Power, a change in
the fuel quality is likely the cause.
Increase the fuel pressure to obtain Set Power, being careful not to exceed the maximum
V
OC
and R
INT
as determined in Section 5.9. It will take 10 minutes for a change in fuel
pressure to take full effect.
WARNING!
Check the maximum V
oc
and R
INT
limits in Section 5.9 before increasing the
fuel pressure. Do NOT exceed the maximum limits.
5.2 BASIC SERVICE
Perform the following service checks at least once a year to ensure safe and prolonged performance
of the Model 8550-RU TEG.
1. Inspect the Cooling System heat pipes. See to Section 5.3
Record findings in the Heat Pipe Inspection Log located at the end of this manual. Create a new
copy of this log for each inspection.
2. Replace the fuel filter in the pressure regulator, see Section 5.4 – Fuel System.
3. Drain the pressure regulator sediment bowl, see Section 5.4 – Fuel System.
4. Check the fuel orifice for clogging and replace if needed, see Section 5.4.
5. Remove debris, sand, and dust from the Heat Pipe fins, cabinet air intake screens, and cabinet
interior.