8HIGH TEMPERATURESAFETY RESET BUTTONFUNCTION SELECTORSWITCHTHERMOSTATKNOBHEATER INDICATORLIGHTINDICATOR VIEWINGHOLEMODEL Z100 SPA(SHOWN WITH HEATER CONTROLS EXPOSED)OPERATIONFunction Selector SwitchTo ensure your safety and allow easy operation, yourspa is equipped with an air-activated function selectorswitch located on the side panel of the redwood skirt, nearthe front corner of the spa. This push-button switch selectsthe following four functions in the continuous sequenceindicated:1. OFF2. WHIRLPOOL3. HEATER/FILTER4. FILTER ONLY(The next selection is OFF again.)You know which function you are selecting when thewhirlpool system is activated. Use that function as areference to indicate your location in the function se-quence, since that function is the most obvious whenoperating.For best performance, pause a second or two betweenpush-button selections.Setting the ThermostatTurn on the heater by selecting the HEATER/FILTERmode on the selector switch. You can verify that the spa'sheater is operating by looking through the small factory-drilled hole located in the door panel of the spa andchecking that the red indictor light is illuminated.The thermostat adjustment knob is located on the frontof the heater. To set the thermostat, turn the knob to thedesired temperature. If the water temperature reaches alevel higher than you wish, turn the thermostat knob backto a lower setting. The spa's water temperature will stabilizeafter a while and fall a few degrees before the heater turnson again. When the water temperature reaches the tem-perature set on the thermostat, the heater and motor/pumpwill turn off automatically.The water temperature will rise at a rate of about 2 0 F perhour, depending on the temperature of the air surroundingthe spa. This rate requires a waiting period before using thespa, the length of which is determined by the temperatureof the water before turning on the heater. For example, ifthe water in the spa is kept at about 70° F when the spa isnot in use and the water temperature at which you plan touse the spa is 100° F, then it will take about 15 hours to heatup to the desired 100°F temperature.Once you have determined the desired setting on thethermostat knob, it is not necessary to change or readjustit again during normal operation unless you decide on adifferent setting.The spa cover provided for your spa will help controlheat loss from the water surface and thereby reduce energyconsumption. You can improve the spa’s heat retention bykeeping the spa cover in place on the spa while heating thewater.Notes on Determining Water Tem-perature:As spa products generally perform in a narrow range ofoperating temperatures, we recommend that you use amedical (clinical) thermometer for an accurate measure-ment of spa water temperature. Other types of thermom-eters generally available, such as those used for swimmingpools, are not sufficiently accurate to determine spa watertemperatures. Take water temperature readings in theHEATER/FILTER mode when the heater has just turnedoff; the indicator lamp on the heater housing will turn off atthis time.