I am working on my retired friend's hottub/spa. I work in electronics, troubleshoot to component level. (history info). Everything works except the heater. The heating element, jets, ect, check ok.

Baja Sports tub, Model # 1050. 115 Vac input. Circuit card is: Gecko EBGX082D, Hydro-Quip Item # 33-0014A. Displays "Prr" after adjusting the heater temperature. The input power cord had a defective GFIC plug-in which tripped when plugging into wall outlet. Replace with standard high current plug and installed a GFIC wall outlet. Found 1/8 amp fuse blown. Replaced fuse. Now "Prr" being displayed.

I have talked with Baja co in AZ. They said to replace the Temp (thermalcouple) probe. Replaced probe and still have same problem. They recommend replacing Circuit card (<$200). I talked with Hydro-Quip. They want $351. No help on component troubleshooting. I talked with Gecko. No help there. Everything is "company secret".

I'am "reverse engineering" the temp probe circuit. Is ther any help available? The probe interfaces with a 8 pin IC, reference des. U-2, IC nomenclature: 2721, 82T, A56J. Can't find any info on this chip either.

I would appreciate any help. The tub owners do not have the available monies for a repair tech. One did come out a year ago to look, took the manual with him and never came back. Sorry for such an in depth request. I can be reached at: (Personal Contact Info Removed by Administrator), e-mail:(Check Profile). My name is Tom. Thank You.

Good luck with that one.

The owners manual would not have been any help to you anyway. Fwiw, Gecko uses an active sensor (something similar to an lm34) rather than thermistors for temperature sensors which further complicate the mix.

Your only option I'm afraid is a lot of hours on the bench, or simply going ahead with a replacement circuit board. I mean, if you were to replace the interface IC (which is probably either an op-amp or an a/d converter) you might end up discovering that the cpu input data line that performs detection of the prr status is defective... negating the value of all the time spent.

I'm reaching for the stars on this one but honestly you'd be better off designing your own system than reverse engineering that one - or if the factory will let you have board for less than $200 you better jump on it quickly as that's darned cheap.

Re-Everything works except heater: Pageup, again I want to thank you for your help.

I reverse engineered the "Temp probe" circuit, made a schematic leaving the "2721" a box with 8 pins, sent it to an engineering friend who modeled the circuit. He determined that the IC was not a 2721 but a 272 I and sent the infor back to me. Knowing what the IC pin out was, I determined the part to be defective and replaced it, reinstalled the circuit card and the spa worked like it should. I also found out that the original temp probe was defective. Replacing the temp probe cos $45 and I had a Op Amp (IC) similar to the 272 I. Bottom line, I was able to repair the Baja Sport Tub for $45.00 but no thanks to Hydro-Quip or Gecko Electroniques in Canada. Neither company would even tell me what the IC was or offer any help. They won't get my vote or my money if ever I was to buy a spa. The retired couple (spa owners) won't be buying anymore of their products!! The company Baja Spas in Arizona were helpful on the error codes but knew nothing about the electronics. I'am going to try and dig out the temp probe and determine whats inside the metal probe. Then if it goes bad again we'll be ready! As I did not charge the owners for labor/repairs, their only out of pocket expense was $45 for a replacment temp probe.

Again, I want to thank you for your help and support. If I can be of help please let me know.

Logi98,
Tom

You won't find any company that will willingly give out any information at the component level of a circuit board. In fact most of the people that work for the companies don't have any accessability to that information. They have a technical team to design the spas, and often contract out the electronics work to other companies (in your case Hydro Quip contracted Gecko to do that). You will run into that problem with any spa manufacturer.