Hydro-Hot Hydronic Heating System Owner’s Manual 08/04
®
Hot Water
,
continued
NOTE:
The Hydro-Hot’s “Domestic Water Priority System” disables
the interior Zone Heating Fans, Zone Circulation Pumps, and the
Engine Preheat Pump (if applicable) whenever domestic hot water is
being used on a continuous basis (i.e. during showers). Once the
demand for continuous domestic hot water ceases the Hydro-Hot
will enable the Fans and Pumps to operate and provide heat to the
Heating Zones. Please note that the Electronic Controller’s Low
Temperature Cuttoff Status indicator light will illuminate GREEN
whenever the Hydro-Hot is able to provide zone heating, reference
Figure 5
.
SECTION 2: OPERATING INSTRUCTIONS
2.4 Using the Engine Preheat System
Engine Preheat (HHE-200 Model Only)
When the Hydro-Hot is at operating temperature, and the
Diesel-Burner
and/or the
120 VAC Electric Heating Element
switch is
ON
, follow these
simple instructions:
A.
Turn the Hydro-Hot's
Engine Preheat
switch
ON
, reference
Figure 2
.
This procedure will activate the Engine Preheat Circulation Pump and
circulate the engine's coolant through the Engine Preheat System.
This feature will adequately warm the engine for easy start-ups on
cool mornings.
Engine
Preheat
Indicator
Light
Diesel
Electric
Engine
Preheat
������������������
Figure 2
NOTE:
Allow approximately 1 to 2 hours of engine preheating run time.
Preheat duration will be shortest when the
Diesel
switch is
ON
.
B.
Turn
OFF
the Aqua-Hot's
Engine Preheat
switch whenever engine
preheating is not desired.
NOTE:
The Hydro-Hot's Engine Preheating System acts as a
supple-
mental heating source
, in addition to the Diesel-Burner and the Electric
Heating Element. While traveling, the engine's heated coolant will auto-
matically pass through the Engine Preheat / Motoraide System, transfer-
ring heat into the Hydro-Hot's Boiler Tank. This design feature reduces the
total operating hours of the Diesel-Burner and the Electric Heating Ele-
ment.
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