- Feb 18, 2009
- 12
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okay im using an old maha steaks cooler a 40w light bulb and the same water heater thermo that i have seen everyone else using. my problem is the big fluctuation in temps when the bulb is on and off. the temps will be 101.1 midrange before thermostat kicks in 92.8 thermostat shuts off at 105.3 i cant get a stable temp. whats wrong or is this normal?