Owner`s manual

Hydro-Hot Hydronic Heating System Shop Manual 07/03

Page 54

NOTE: In order to perform some of the following procedures it may be

necessary to detach and reattach the Diesel-Burner Head. Be sure to

reference Section 8.2, Page 42 for detaching and reattaching instruc-

tions.

Component Test:

Clamp

off and remove the Hydro-Hot's Fuel Return and Fuel Supply Lines,

reference Figure 1. Attach a short piece of fuel line to both the Hydro-Hot's

Fuel Return and Fuel Supply ports, reference Figure 1. Submerse the

opposite end of the temporary fuel supply line in a container of diesel fuel.

Place the opposite end of the temporary fuel return line in an empty

container. Turn the Diesel switch ON to activate the Diesel-Burner, refer-

ence Figure 4. If fuel does not flow out of the return line into the empty

container, the Fuel Pump must be replaced, reference the Fuel Pump's

"Replacement Procedure" on Page 58. Reference Section 10 for spare

parts information.

NOTE: Prior

to replacing the Fuel Pump, be sure to inspect the Screen

Filter in the supply inlet of the Fuel Pump, for dirt particles (reference

Figure 19). Clean and/or replace, if necessary. A plugged Screen Filter

will restrict fuel from entering the Fuel Pump. Reference the Hydro-Hot's

"Parts Manual" for spare parts information.

Cleaning Tips / Maintenance:

1. Check all Fuel Connections for tightness (i.e. Banjo Bolts, High

Pressure Fuel Pipe Connections, reference Figure 19.

2. Check the Screen Filter, located in the fuel supply inlet of the Fuel

Pump, for dirt particles. Clean and/or replace, if necessary (refer-

ence Figure 19).

Function: The Fuel Pump draws diesel fuel from the vehicle's fuel tank

and creates a preset pressure of 145 psi (required for proper fuel atomi-

zation). Reference

the illustration below for a basic overview and under-

standing of how the Fuel Pump functions.

Section 8: Diesel-Burner Service, Maintenance, and Repair Information

Fuel Pump

8.8 Fuel Pump

1. Fuel Nozzle

Air Relief Bore

3. Fuel Supply Line

4. Fuel Return Line

5. Fuel Pressure Regulator

6. Fuel Solenoid

FUEL PUMP

OVERVIEW