No temp adjustment

Sundance 99,750 with sentry command center .we can’t adjust the heat either warmer or coler . Stuck on 37c. Just took possession of house and it came with the tub , have any suggestions to adjust heat ?

16 thoughts on “No temp adjustment”

  1. Jeff, when you press the warmer or cooler buttons does the control panel LED display  “Loc”?  Also when you say it is stuck on 37c, when you press the warmer or cooler buttons does the temperature setting go up or down, also when you press a pump or air blower button do they turn on or does the control panel appear to be locked and non responsive to any touch?

  2. Jeff if all the other buttons work including the warmer and cooler buttons and you have water movement but the spa will just not get warmer then 37.0c make sure your heathield (hot tub cover is on the spa) while trying to raise the heat and make sure the warmer arrow has been depressed enough times to show that you have set it higher then 37.0c.  Also make sure that you have the control panel toggled to STADARD mode.  The spa will only heat during a filter cycle if the panel is set to ECONOMY mode.  Make sure your circ pump is set to run 24hrs.  That model has a limit of 40.0c.  If this all checks out and you can’t get it higher then 37.0c but it is maintaining heat at 37.0c ie when the temperature drops below 37.0c it goes back up again automatically to 37.0c you may have a bad connection where the temp sensor wires connect to the sensor harness at the PWA.  You may also have a bad temp sensor.  You can check your connections at the sensor harness by removing the harness from the PWA and gently tugging on both temp sensor wires individually.  Check the wire and the insulation around it from where it leaves the sensor harness to the temp sensor body for abrasions/cuts etc.  Mice like to live in warm areas like inside the equipment bay of a spa especially in colder regions and they can chew through these wires.  If the wires are secure you may have a bad temp sensor.  If all else fails contact your local Sundance Support Desk to book a diagnostic and repair of your Sundance 750 series spa.

  3. All buttons do work , other than warmer or cooler . When I press either button nothing happens. Shouldn’t it read “set” , yes it is in standard mode , seems like pump/heater are set or stuck at 37c . Cover is also on all the time . Where abouts would the heat sensor be located ?

  4. It was the sentry command centre , got part from aqua- tech all good now ! Can you tell me the montego 750 which is the tub . Is that a good insulated tub to run all winter ?

  5. Jeff, the Montego was manufactured to run through winter.  Best practice is to check the spa once a day through the winter by lifting the heathield spa cover and checking for water flow and heat setting.  Set your circulation pump to run 24hrs and set all 4 filter cycles to run 6 hrs each consecutively.  Have the water tested at our lab 1x month.  Test your GFCI 1x month.  If the spa will not be used or not be monitored for a prolonged period of time consider winterizing it or having it professionaly winterized.

  6. All is working good now, but I can’t find anywhere in the manual how many litres the montego is . In order for me to properly balance the water. Can you please let me know .

  7. Good Morning Jeff:

    I am very glad that your spa is working well. The Montego volume is 1463 litres. Please feel free to bring in one litre of water any time for free analysis and recommendations.

    Happy Hot Tubbing!

  8. have a sundance montego 1997 was working great then top controler stopped responding cant adjust heat stays on 94 cant lower or raise and spa light stoped as air pump jet two only action that works and has a mine of its own sometimes do i need a new top side controler and can you supply thanks paul

    1. Paul it sounds like you may have a bad topside control panel. If you go to our online store and click on Parts and accessories, then click on the big yellow button Prices and Availability. Ask for part number 893030013.

  9. i have a sundance spa system my control pad the temp buttons only go down it wont go up its like the warmer button don’t even work i bought a new control pad off ebay but i didn’t fix the problem any help will greatly appreachead

  10. I have same problem. I replaced top control thinking the same thing but it didn’t fix problem. All buttons work but temp- temp + makes display show 94 and nothing changes up or down.

  11. Hello, This is the only website that talks about the Sundance Spa temp increase button not working. This must be an issue but no one has sated if it’s the control panel or if there is any way to bypass the temp increase button. As of now I only use my 2003 Sundance Capri 3-4 months out of the year. This came with my home and I would like to keep it but I cannot afford the monthly service or maintenance fees especially if I use part of the year. I called the spa company and they said that the temp bulb was replaced in 2014. I tested the temp Bulb by placing a ziplock bag by the bulb and temp decreased to 65 degrees Fahrenheit. The heater came on. I placed a infrared thermometer on the heater, entrance and exit tubing prior and before adding the bag of ice and have different readings. I cannot find anywhere online or my local spa company will not tell me the resistance rating for any of the sensors. I would be able to tell what is going bad. I replaced the heater and high limit sensor and still the same problem. I cannot reset my LCD ribbon tape since it’s sealed with epoxy. The only way I know of bypassing the heat button is by adding a resistor to the two temp bulbs. If I add a 1K Ohm resistor to the temp line giving a false reading that its cold the heater will heat the water. The high limit sensor would be left alone so that the heat would not go past 104 degrees. It’s time consuming but this saves me $500 for a panel that has one button inoperative. No faults when in troubleshoot mode.

    1. Hi Reggie. If you are getting a different reading on your topside then the actual water temp then you could have a bad temp sensor or a slight flow issue that is not enough to be causing the FLO message. If both buttons on the topside work ie they raise the temp readout up and down there is likely nothing wrong with it as the topside does not hold any memory but you probably know that. Anyhow easiest way to test for a bad temp sensor is put a real thermometer in the filter pot near the temp sensor. If your confident your thermometer is accurate and the temp differential between it and your topside readout is more than 2 degrees you may have a bad temp sensor. The resistance chart for the temp sensor has a wide range. It’s based on the temperature of the water. If you could tell me your accurate water temperature I could tell you what resistance the sensor is supposed to be reading. 15 Celsius should be 48840 ohms. 45 Celsius should be 13281 ohms. 28 Celsius should be 26400 ohms. Fyi only these resistance readings would be the same for your hi-limit sensor.

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