Hi everyone, I have just purchased a brand new Pacific Spa hottub, and it has a xm series controller, in.k400, it also says Aeware on the top of the controller, anyway the thermostat will not let the hottub get any hotter than 104, it works fine and the tub is calibrated to exactly what the thermostat says,I bought a medical thermometer to check, I did call the manufacturer and they said its a CSA thing that any new hottub sold in Canada has that restriction on it for safety,
Where I live the weather drops to -15 to -20 and even when its +10 outside I really need the tub to be at least 106, I know some people like there tubs cooler but I like mine really hot, and after sitting in the tub for 30 minutes it drops to 102 which is like a warm bath to me.
So what I would like to know if there is anyway or ony one that knows how to recalibrate this thermostat so as I can get the tub a little hotter, I dont care if it voids warranty or anything because at this point buying a hottub that doesnt go any higher than 104 for me is just a waste of money and I cant even be bothered to sit in it.
Any help or suggestions would be great.
Thanks

Hi There,

Could be a number of factors at work here, over and above what the supplier has suggested:

1. Tubs can be set to load shed in order to reduce the size of the required supply. Essentially this means that the heater cuts out when the pumps/blower are activated. Your controller could be mis-configured to load shed, or your supply may be too small. You can check this - look at the display on the spa (most have a heat symbol), if you activate all of the pumps/blowers one at a time until the light/indictaor goes off; then you know that the system is load shedding.

2. Could be the hysteresis of the thermostat - "tight" is say +/- 0.25 deg, "loose" is say +/- 2deg. On our Spa Net control system, the default setting is loose, unless you fit an in-pool-temp-sensor which increases the sensitivity to "tight". An in pool sensor looks like a sliver metal disc or ballbearing set into a plastic fitting in the wall of the pool - it may be possible to retro-fit one to increase the sensitivity.

3. You may have a tiny heater - even the most expensive hot spring hot tubs in the UK have 1.5kw heaters which is nowhere near adequate for long outdoor sessions in cold weather. Most large tubs need at least a 3kw in the UK.

4. Some systems make it quite easy for the heater to be installed back-to-front. If this happens, then the heat sensors are after the heater, not before it; so as the water flows thru the system, instead of the heat sensor measuring the "pool" temp, its actually measuing the temp of water thats just been past the element. This confuses the system by giving it a hotter reading than it should so it thinks the spa is hotter than it is. You can check this with a floating thermometer - a couple of £ or $ from your local pool shop. (As you have tested yours, its probably not this, but helpful for people with a similar problem searching the forum...)

You can reduce the cooling effect by not using the air blower, or by turning off the air controls for the jets - this will reduce the amount of cold air blown thru the jets and reduce the rate of cooling.

I would NEVER suggest overriding with the system - the overtemp cut out is a vital safety device that acts as a failsafe in the event of a malfunction. This cuts the heater if the temp exceeds 42deg Celcius. Anything above this and you could fall prone to Hyperthermia (opposite of hypothermia) where the body overheats which can cause unconsiousness, followed by drowning.

Good luck!

Let us know how u get on.

Ed.

As suggested, the big problem is the temp drop, not the high temperature. You'll feel a drop from 106 to 103 the same as you do from 104 to 101. Knowing your heater size and surface area will help determine what you can hope to achieve. It may be that a gas heater is your only option to keep your tub at 104 when it's -15 out.