Tub won't heat Message SL - Pool & Spa

You have it in "Sleep" mode. Spa will not heat normally in this mode...

If the SL Message is Alternating with the Water Temp in the Display Screen (we call this "Flashing Sleep"), the Spa is Operating in the Sleep Heating Mode.

If the SL Message is ON Solid (Not Flashing) in the Display window of the panel, the Spa is Operating in the Sleep Heating Mode, but there is No current water temperature because the Spa is between Filter Cycles.

Between Filter Cycles, while in the Economy or Sleep Heating Modes, the Pump has not turned ON and the Last Water Temperature is not Current. To read the Current Water Temperature, either Change to Standard Heating Mode or turn On the Heating Related Pump, and wait at least 2 Minutes.

SL or SLP is one of the Modes you can program your spa into:
EC - Economy
ST/Std - Standard
SL/SLP - Sleep

It is advised you keep your spa in Standard mode. Push the Jets button then immediately push the light button. Each press of the light button will scroll between these three modes.

Good Luck

there may be a bad head gasket. The plugs need to be removed and checked for water and a compression check should be done.

If the SLP or SL Message is Alternating with the Water Temperature on the Display, the Spa is Operating in the Sleep Heating Mode.

If the SLP or SL Message is ON Solid (Not Flashing) on the Display, the Spa is Operating in the Sleep Heating Mode, but there is No current water temperature because the Spa is between Filter Cycles.

Hope this helps.
US Parts Center

SLP or SL Message

If the SLP or SL Message is Alternating with the Water Temperature on the Display, the Spa is Operating in the Sleep Heating Mode.

If the SLP or SL Message is ON Solid (Not Flashing) on the Display, the Spa is Operating in the Sleep Heating Mode, but there is No current water temperature because the Spa is between Filter Cycles.

You can find answers to common spa panel messages on the following page:

COMMON SPA PANEL MESSAGES

In line heaters will not HEAT the water, they will only maintain the temperature inside the tub within a few degrees. You should not try to install the heater yourself, it would be best to have a plumber come over and give you a quote on how much it would be to install it. A plumber can look at the tub, see if there is a place that the heater can be CUT IN to the pipes, and install it. You likely won't get it to work. The inline heaters are required to be put on a GFCI circuit because they are powered in a wet environment. Unless your tub is not hardwired in to the house, and you actually have a GFCI circuit under the tub. But like I said, these do not heat the tub, they only maintain. And the life of these is not very long if you use soaps and shampoos in the tub while the heater is on. It won't take any time at all for the oils to build up on the elements, rendering it useless.

Need to know what buttons your topside control has... depending on the model, some have a mode button which you press and release and then immediately press the temp up or down, to select SL for sleep (no heat), ST for standard (heat as needed) or EC for Economy (only heat during filtration). If the mode button is not present, and you have a single temp button and light button, try pressing and releasing temp and then immediately pressing light button, repeat until choice appears, then wait, it will hold last displayed mode.

sl means sleep mode and will not heat! try depressing the temp button the either the light button or the jet button usually that will change modes u want st or std mode which means standard. or if u have a mode button try that 1st. or email me a copy of control head to [email protected] for tips! thanks Bob

tub is in sleep mode usually to change u must press temp button then light button you want to b on standard mode STD