I want to build a wifi connected controller for my hot tub so I can know the current temperature,...

[G+_Tom Frillman]

I want to build a wifi connected controller for my hot tub so I can know the current temperature, turn on the pump and heater that will auto turn off when at a set temp, etc.

I think that some of the Grow How episodes have a controller that might be the basis for what I want to do.

How can I find those episodes?

Does anyone know someone who already has done something similar?

I'm a noob at electronics and programming too so I need all the help I can get.

Thanks for reading and your feedback.

[G+_Paul Hutchinson]

A DIY controller is only appropriate if the risk of a catastrophic control failure is acceptable. With a small plant growing system the risk is typically a dead plant and some dead low cost electronics. With a hot tub the risk is a dead pump or heater, either of which might be too expensive to be an acceptable risk.

 

The way I would approach the decision to buy or build this kind of system is to compare the cost of a pump plus a heater plus support components against the cost of a professionally designed and manufactured controller.

 

If there is no ready made controller with the features available, I consider if the convenience features are worth the risk of breaking the pump and/or heater.

[G+_Tom Frillman]

Paul Hutchinson Thanks Paul but cost is low on my list of priorities. I have been using a watering timer that has a remote control on the system for years without issue; except inconvenience. I have to go out, multiple times, with a thermometer to check the temperature and I have to be within 10 meters of the timer with the remote.

I am going to install one or more temp sensors in the tub to control the feedback loop.

As far as safety goes there are both water-flow and temperature controls in the heater. If the pump fails the the water-flow sensor won't all the gas valve to open, and I will be adding to the California maximum, 107°F hot tub, temperature safety rule with a sensor in the tub.

Internet connectivity will also be a big help to monitor tub when I am on vacation or leaving the bar with a "new" friend.

[G+_Paul Hutchinson]

Tom Frillman if cost is low on your priority list then getting a commercially made solution is the way to go. It will save an enormous amount of time for a self professed "noob at electronics and programming" (actually it would save tons of time for even a 40 year electronics design and programming professional like me) and be backed by a warranty.

 

Here's one example of a product that may do everything you want:

arcticspas.com - OnSpa - Like OnStar for hot tubs, wireless hot tub control

[G+_Tom Frillman]

Paul Hutchinson Again, Thank you for the information and the link.

Unfortunately I don't have a spa/jacuzzi--I have a redwood hot tub without any digital control.

I inserted a relay in order to use the sprinkler timer to turn the heater/pump on/off on a schedule or on demand via the remote control. This system uses the heater thermostat which is difficult to calibrate and if changed requires recalibration.

The On-Spa and and Balboa systems that I looked at appear to modify the digital controls on current era spas and are not designed to upgrade from analog to digital.

Thanks again for the input.

[G+_John Sullivan]

Tom Frillman You might try contacting "Fran Michalak" in this Group. He has been working on something similar and may be able to help.

[G+_Golden Retriever]

I wonder if you could use one of those voice assistant connected thermostat things like you used to control your HVAC / furnace in your house.

[G+_Steven Werds]

If your looking for all those features have you thought about the raspberry pi as the controller

[G+_Steven Werds]

If you want Wifi the easiest way to go would be a raspberry pi. want it to have a read out in the house just use a simple PHP script that would receive the information then have the HTML page refresh like every 60 seconds with the new update.

the code to send to the Apache server would be something like

 

http://Your IP Address/results?temp=102&status=ON

 

you can pass any information that you want, just make sure it is not sensitive data.

 

The trick is the raspberry pi must be treated with much more care than an Arduino.

 

And set up and understanding may be a bit more of a curve if you do not know Linux.

 

but if you know any programming then you may find that you do not have to learn a new programming language, you just need the extentions for the pins in your Languages.