Caldera Spa's Martinique 1999

[tfcfckvffuk]

I have a 1999 Caldera Spa's Martinique. Yes, I know it's an old model, but I'm renting a house and it's permanently installed, so it can either be a swamp (as when I moved in) or a functional tub. It seems to work fine, but I have one problem and one question:

Problem: the circulation pump kicks in for a minimum of 2 hours twice a day (4 hours total), and when it does, the heater kicks in as well. This is a problem because the minimum temperature on the spa is 80F, so for 4h a day it's running the heater to get from 60F (or whatever ambient is) up to 80F, even though I don't plan on using it for a week or maybe more. Is there any way to disable this? I imagine I'd have to mess with the logic control board...

Question: I know that all of the functions work because I can test them (i.e. jets, filter, light, etc.) but the one thing I cannot test is the ozone generator (which I can see is installed). There is no error code being displayed, but that doesn't mean it is working. Does anyone know how I can check this?

Thank you!

[Jersey Hot Tub Repair]

It would help if we had a photo of the control box.  At that age, the hot tub may have either a digital circuit or mechanical relays, and that would affect the answer to your first question about filtration and heating.  How do you set the temperature, by push button and an LED/LCD screen, or is it a rheostat that you rotate?

Ozone generators use ultraviolet coronas or lamps which tend to have a 1 to 2 year life span.  Chances are, if the hot tub was a swamp when you moved in, the last owner didn't take care of it and my guess is the ozonator needs replacement.  There are company's selling ozone test strips, but they will generally say they are inconclusive for hot tubs because the amount of ozone generated is quickly diluted and difficult to measure.

 

 

[tfcfckvffuk]

Scuba, thanks for the very helpful post. I'm 99% sure all of the controls are electronic. I opened it up and took some pics. I contacted the manufacturer and they didn't seem to want to help. I may look into highjacking the thermocouple or however it sense temperature to read 100F to the board whenever it is in econ. Has anyone done this before?

The ozone unit doesn't look all that serviceable, and it doesn't have any part numbers on it, but I guess I can call a local rep and check.

[tfcfckvffuk]

Scuba, thanks for the very helpful post. I'm 99% sure all of the controls are electronic. I opened it up and took some pics. It looks like the control board was made by a local company, so I'm going to try to give them a call tomorrow.

The ozone unit doesn't look all that serviceable, and it doesn't have any part numbers on it, but I guess I can call a local rep and check.

Images:

photo hosting ebay

[Jersey Hot Tub Repair]

OK.  You have a Balboa control system, which is a very common system.  Balboa makes the guts used in probably 35 - 40% of the hot tubs out there.

Here's a 1999 Caldera manual that may help you:   http://www.thespaworks.com/sites/default/files/1999_paradise_series_owners_manual.pdf

Your tub is already set for the minimum filtering (2 hrs) and temperature, so the only way to change that is to shut it off.  I'd strongly recommend against that.  That's the minimum amount of time the manufacturer felt was necessary to keep the water clean.  If you want to save money on electricity, I get it, but if you let the tub sit for a week in the hot sun, it will become a bacteria farm without filtering and disinfection.

You could disconnect the heater so it doesn't turn on when the tub goes into filtering mode, but that seems like a lot of effort to open the tub every week ten hours before you want to take a dip.  Of course, if you're in a location where freezing is an issue, you better stay on top of it, your landlord's going to be pretty ticked off if you freeze up his spa and leave a pile of cracked pipes.

You could also put the temperature sensor in a cup of warm water (or whatever method you can dream up) to fool the tub into thinking it doesn't need the heater.  There are two sensors in there, a hi limit sensor and a temp sensor, so obviously make sure you play with the right one.

The ozonator can be replaced with just about any ozonator on the market, just make sure you get the proper voltage.  If the ozonator doesn't have the voltage printed on it, trace the wires back to the circuit board and put a multimeter across them to see what voltage the board's putting out.   I'd guess that 80-90% of the ozonators across the USA are dead and the homeowners aren't aware of it, point being the tub can run without it, as long as it doesn't short out from water backflow.

 

 

[tfcfckvffuk]

Scuba,

Thank you, that makes sense. I do agree with you on not wanting to turn it off: it gets gross within a two days or so. That's why I'm trying to get the best of both worlds: I'd like to run the filtering cycle for the 4h a day the manufacturer deemed minimum, but I do not want to be heating up the tub during this time. What I was thinking is I would just install a switch on one of the temperature sensors and then mount it on the outside of the tub so all I have to do is flip an extra switch to allow the tub to sense the actual temp and thus turn the heater on when I actually want to use it. If there is a hi limit sensor, is this a binary signal or a continuous temp signal? If it is binary it should be quite easy to install such a switch in between that and the control unit.

So for the ozonator, I should just buy a new one (i.e. not replace the lamp, chip or whatever it is that it uses)?

Thank you

[Jersey Hot Tub Repair]

The temp sensor works by measuring the resistance in the circuit.  Just putting a switch in-line will affect the resistance, so I don't know what to tell you about that.   Same for the hi limit sensor.

Although not shown in your photos, you probably have a pressure switch mounted in the back of the heater tube.  It would look something like this:

https://www.amazon.com/Pressure-Switch-Spa-Universal-Video/dp/B01A9DZA0W

That is a simple 12V on/off circuit that determines if water is flowing in the heater tube.  If the pressure switch doesn't sense water flow, it turns off the heater.  So you could add a switch in that circuit if you want.  The tub will give you a FLO error, but I suppose that could let you know that the heater is shut off.  I'm not sure if that will prevent  the filtration cycle from running, you'll have to let me know.

Your ozonator probably has an ultraviolet light bulb in it, I suppose you could open it up and see if you can replace it.  Most of them are soldered in, not replaceable, but I don't know what Caldera was doing 20 years ago....

 

[tfcfckvffuk]

Hmm. So I found the connectors for both temperature sensors. I tried unplugging them and I get a Sn1 error, which according to the manual means the sensor malfunctioned (duh), but unfortunately it also shuts down the whole tub. If the HI TEMP sensor detects >112F, it also shuts the tub down completely. The same is the case if it detects a problem with the flowrate (so I don't think disconnecting the pressure switch would work either). The only options I see is to disconnect the heater power directly. I unhooked it and turned it on. It hasn't blown up yet, we'll see what happens when the skim cycle kicks in in a few minutes. If it works fine, then I'm just going to buy a 240V 30A remote relay  and connect that in there. Maybe I'll got with a connected relay, then I can say I have a "smart" hot tub 

[Jersey Hot Tub Repair]

There's no safety issue in running the tub with the heater disconnected.  Of course, you have to protect those loose wires so they don't short out against a hot component.

I would have misgivings about putting a switch in the heater circuit to disconnect it.  Aside from the fact that you're playing with a lot of voltage and amperage, the tub is designed with fail-safes, grounds and bonding. Is the switch going to be grounded?  What if that switch went bad, 10 years from now, is there going to be a safety to protect who ever is touching it then?  A hot tub requires a GFCI.  Will your switch be protected by that GFCI, or will it be avoiding the GFCI?  If you touch the switch when you're barefoot, is your body going to act as a ground?  How about in 10 years when the switch goes bad and the current occupant doesn't realize what he or she has there?  Will they be at a risk of electrocution?  Tampering with the design of that tub just doesn't sound like a good idea to me.

As a hot tub serviceman, I wouldn't put a switch in the heater circuit because that changes the design on a system that is UL listed, and if something happened in the future to the tub or a bather, you could be responsible. 

I don't mean to criticize you, I'm just sharing my concern for your safety.

 

[tfcfckvffuk]

Scuba,

You have some good points, and I thought about how I would mitigate them. To be more specific in my approach:

(1) A low voltage (i.e. 12V battery) operated RF relay so that I can just put the RF controller right next to the circuit breaker (which is on the wall of the house closest to the tub). Then connect this directly to the existing heater relay (which is I think connected directly to the High Temp relay).

(2) Same remote 12V relay as above, but connected to a heavy duty contactor or relay (rated for 4kW).

Either of these I think would satisfy most of the concerns you listed since (a) I should be able to attach them to the tub's existing ground and (b) it'd be installed inside the control module's housing so I don't think anyone would be at risk of electrocuting themselves. I'll also add that I am likely the last tenant in this house before it gets remodeled, which would likely do away with the tub anyhow.

Obviously (1) is ideal because it would be cheaper and require fewer modifications, but I am not sure how I'd wire that and I may have to access the back of the PCB. If you can offer any advice on this I'd appreciate it. I'm attaching a close-up of how it's wired, and the link to the datasheet for the existing relays.

http://www.alliedelec.com/american-zettler-inc-az2120-1a-15df/70132409/

[Jersey Hot Tub Repair]

As I said, I wouldn't do it myself, but by using a remote controlled relay you are at least removing the issue of a person getting shocked from touching an improperly wired switch.

Balboa uses two types of heater elements, a 4.0kW and a 5.5kW, so you may want to go with a larger relay.  You can measure the amperage on the wires, it'll probably be somewhere between 12 and 18 AMPS, depending upon the age of the element.   A not too common cause of circuit board damage is when the heating element goes bad - it can suddenly draw 25 or even more AMPS, and the relay's fry before the board shuts itself down.

When they build hot tubs, they design them for 80% of potential power use, so a 48AMP hot tub will recommend the use of a 60 AMP circuit.  Point being, you should probably allow for extra capacity.