A1.3
Pumps
TACO brand pumps are used extensively on HoloTech systems. On the smaller pumps, the
bodies can be disassembled and the rotor cartridge replaced without removing the pump from
the line. For detailed drawings of the components, check the pump literature. Replacement
parts are available from Holocene. The pumps have shut-off flanges which allow the lines to be
closed off and the pump removed without draining the system.
Table A1.3
Pump Troubleshooting Table
1. Pump runs hot, pumps water
OK - Normal operation
2. Pump hums, does not pump water
Rotor frozen or jammed
Capacitor or windings bad
3. Pump runs, pumps water, flow stops Height greater than pump head
Air locked lines (traps in lines)
If a pump does not pump water, the first test should be to swap out the capacitor. If this
does not work, remove the cartridge to see if the impeller is frozen. Sometimes a frozen
impeller can be freed by turning the shaft with the hand. However, in most cases, once
a pump impeller freezes, it does not last long after that. Changing out the impeller
cartridge is recommended. If the impeller is free, a short live test will determine if the
impeller will spin. Do not run the pump long with the impeller in the air. With no cooling,
heat will damage the bearings. If the impeller is free and the live test does not work, the
field coil windings may be bad and the motor must be replaced.
HoloTech
tm
Solar Installation Manual
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