American Water Heater 318281-000 ユーザーズマニュアル

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The chemical composition of the HTF may change over 

time. The HTF quality should be monitored on a periodic 

basis – at least annually. After summer and before any 

chance of the first freeze is an ideal time. A drop in ph can 

indicate the system has been stagnating frequently. The 

cause should be determined and corrected. 

To test the pH level, use a digital ph tester or tight range 

litmus paper. Remove a small sample of the fluid from the 

airstop on the pump station. The pH should be between 

8.1 and 12.0. Fluid with pH between 7.5 and 8.1 can be 

conditioned by your contractor using an inhibitor boost. Fluid 

with pH above 12.0 or that is dark, dirty or has an acidic 

smell should be replaced. 

On an annual basis, all piping should be checked for leakage 

at joints, and unions. Any damaged external insulation 

should be repaired or replaced. 

On an annual basis, check wiring and connections, including 

sensor wiring and splices. Look for signs of overheating, 

discoloration, corrosion or loose connections. Any damaged 

wiring should be repaired or replaced. 

If you detect a glycol or water leak, or the glycol loop 

pressure drops unexpectedly, contact your installation 

contractor immediately to diagnose the problem and 

recharge the system. 

If you live in a dusty climate, once a month wash off dirt that 

settles on the solar panel glass. Clean glass allows the solar 

panel to maintain a high level of thermal performance. 

Annually check condition of the solar expansion tank. Check 

to see if it is waterlogged by quickly pressing schrader valve 

stem at bottom of the tank. You should get a quick burst of 

air. If fluid is discharged, the tank may be waterlogged and 

need replacement. Contact a qualified solar installer if the 
tank needs replacement. 

For extended periods with no hotwater usage such as 
vacation it is recommend that the max. tank temperature 
(S MX) in the solar control be set to 120°F. This maximizes 
the storage capaicity of heat build-up during the day using 
the CMX function for maximum collector temperature and 
will aid in preventing breakdown of the heat transfer fluid 
due to overheating.