Determining the cause of overheating can be difficult. Here
are some things to look for:
1. Wire Reinforced Rubber Hose:
Could the rubber hose part of the piping between the engine and the
GRIDCOOLER®
be collapsed? This could cut the cooling water supply to the
GRIDCOOLER
and reduce its efficiency. Be sure you are using wire reinforced rubber hose.
2. Piping:
Is the piping between the engine and the
GRIDCOOLER
as large or larger than the engine and
GRIDCOOLER
connections? (See section 2.7.4 under plumbing.) The piping should also be self-venting and arranged so
that a minimum number of elbows are used.
3. Jacket Water:
Is the jacket water circulating through the
GRIDCOOLER?
It may be taking a path of least resistance through the bypass (if one exists).
4. Thermostat:
Could the thermostat be stuck or could the wrong thermostat be in use? If so, it could give you a faulty
temperature.
5. Jacket Water Pump:
Is the jacket water pump working properly? If not, it could reduce the cooling systems efficiency.
6. Air in the System:
Was the
GRIDCOOLER
installed in a way to allow all the air in the system to escape? When a U-Flow (two-pass)
GRIDCOOLER
is mounted on the rake of the vessel, make sure that the nozzles are mounted in the up or high position. See sections 2.3.6
- 2.7.6 - 2.7.7 -
2.8.3 under Installation. See Figure 17 of installation.
7. Foreign Matter:
Could anything have gotten into the cooler nozzles? Make sure that the orange plastic cap plugs covering the
ends of the hose connectors were removed and that no foreign matter, such as a rag, was dropped into the cooler nozzles.
8. Expansion Tank:
Could the water level be too low in the expansion tank? This can reduce the cooling system's efficiency.
9. Coated
GRIDCOOLER:
Is the
GRIDCOOLER
painted or covered with any other coating? This would have an insulating effect and will greatly reduce the heat transfer rate of the unit.
10. Water Aeration:
Could the water around the
GRIDCOOLER
be aerated in any way? Aeration will reduce the heat transfer rate of the
GRIDCOOLER.
11. Moored at Dock:
Is the engine temperature rising while the vessel is moored in dock? If the
GRIDCOOLER
is installed near the propeller, engage the propeller to circulate water past the
GRIDCOOLER,
after taking the proper safety precautions.
12.
GRIDCOOLER
Placement:
Is an aftercooler circuit overheating? Make sure that the
GRIDCOOLER
cooling this circuit is mounted forward of or closer to the skeg or keel than the jacket water coolers.
13. Mounting Gaskets:
Were the mounting gaskets put in place when the
GRIDCOOLER
was installed? The mounting gaskets supplied with the
GRIDCOOLER
must be used to provide adequate spacing between the
GRIDCOOLER
and the ship's hull. This will allow water to flow freely over the cooler tubes.
14. Glycol:
How much glycol (antifreeze) is in the system? Perhaps the
GRIDCOOLER
was not sized for the use of glycol in the system.
NOTE: Always premix glycol with water before adding it to the cooling system.
15. Crushed Tubes:
Have the rectangular tubes on the
GRIDCOOLER
been crushed or pinched? This could restrict the internal water flow
16. Blown Tubes:
Could the rectangular tubes on the
GRIDCOOLER
have been blown or bulged by unusually high pressures? If so, the exterior water flow past the
GRIDCOOLER
tubes could be impaired, retarding heat transfer. NOTE: Maximum
GRIDCOOLER
test pressure is 35 PSI (2.41 BAR).
17. Marine Growth:
Has your vessel been in dock for several months? You may find marine growth on the
GRIDCOOLER
which will hinder the unit's heat transfer rate. See Cleaning.
18. Oil Deposits:
Have you had engine problems? Oil may have gotten into the cooling water system and collected in the
GRIDCOOLER,
coating it with an oil film. See Cleaning.
19. Mineral Deposits:
Could you be using hard water in the system? Mineral Deposits will collect on the tube in the
GRIDCOOLER,
lining the inside with lime, calcium, etc. See Cleaning.
