Onan DYG Series Operator's Manual And Parts Catalog page 16

C I T Y WATER C O O L I N G
An optional method of engine cooling, in place of the
conventional radiator and fan, uses a constant
pressure water supply. This is referred to as CITY
WATER C O O L I N G . There are two varieties of city
water cooling; the HEAT EXCHANGER SYSTEM and
STANDPIPE SYSTEM. See Figures 6 and 7.
V E X P A N S I O N .
T A N K
F R O M
- — H E A T E X C H A N G E R
• T O E N G I N E
E N G I N E
J
D R A I N
S O L E N O I D
V A L V E
( O P E N S W H E N
, , P L A N T I S R U N N I N G ) -
J
7 -
ADJUSTABLE
VALVE
(RATE OF FLOW)
8 3 8
Z ^ T t w A T E R
j ^ S I N
S T R A I N E R
A N T I - S I P H O N — II
S T A N D
P I P E
S O L E N O I D V A L V E
( O P E N S W H E N
P L A N T IS R U N N I N G )
W A T E R
I N
<3«
D R A I N
— F R O M
E N G I N E
ADJUSTABLE •
VALVE
(RATE OF FLOW)
i T O E N G I N E
S T R A I N E R
FIGURE 7. TYPICAL STANDPIPE SYSTEM
The STANDPIPE SYSTEM uses a mixing or temper-
ing tank. Cooling water"that circulates through the
engine mixes with a source of cool "raw" water. The
• "raw" water supply must be free of scale forming lime
or other impurities.
FIGURE 6. TYPICAL HEAT EXCHANGER SYSTEM
On both systems use flexible pipe for connecting
water supply and outlet flow pipes to engine. Pipethe
outlet flow to a convenient drain. Install an electric
solenoid valve and a rate of flow valve in the water
supply line. The electric solenoid valve opens and
allows water flow through the system only when the
plant operates, t h e rate of flow valve, either
automatic or manual, provides forthe proper flow rate
to the engine. Adjust the flow to maintain water
temperature between 165° F and 195° F (73.9° C and
90.6° C) while viewing the water temperature gauge.
The HEAT EXCHANGER provides foraclosed engine
cooling system. Enginecoolantflows through atubed
chamber, keeping the coolant separate from the cool
"raw" water supply. The coolant chamber must be
filled for operation, as for a radiator cooled set.
Before filling cooling system check all hardware for security This
includes hose clamps, capscrews, fittings and connections.* Use
flexible coolant lines with heat exchanger, standpipe or remote
mounting radiator.
WATER J A C K E T HEATER (Optional)
This heater is installed to maintain an elevated engine
temperature in lower . ambient temperature
applications. It heats and circulates engine coolant,
and.is thermostatically controlled.
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