Hello, how can I help you today? If you're going up to 108 degrees in the spa, then the most likely cause is your temp sensor, this is primarily what controls how hot the spa is allowed to get. The hi limit sensor that throws up the OH code is mounted right on the heater, so if it were the heater itself that was overheating and not the spa water, you'd just be getting the OH and the water would still be at normal temperature, not actually overheated. The temp sensor is easily replaced and just plugs into the board, the only problem you occassionaly run in to is if they've covered it with foam and you have to dig it out. The easiest way to track it is just locate on the board where it says the sensor plugs in, then follow the wire to the sensor from there.
ok, so you are recommending I replace the hi limit sensor?
I see the sensor, it looks to be on the left side of the heater.
part # XXXXX the hi limit sensor?
no, it sounds like it's your temp sensor that's the problem, as it's what controls how hot it allows the heater to go, and if you're setting the spa for 104 and it's going up past that, then it's the temp sensor, either that or you've got a relay stuck shut on the board that's allowing the heater to stay on all the time, but that doesn't happen very often. The high limit sensor is doing what it's supposed to do and shutting the heater down when the water overheats, usually when the HL sensor goes bad, it starts showing OH when the spa isn't even heated up, but yours is actually overheating from what you've told me.
They've used a few different sensors on those, check where it's connected to the board, on most models the high limit and temp sensor are both on the same board receptacle and if you change one, you have to change both of them at the same time.
also, if you can see the white label on the board that has the board number on it, we can track the sensors from that number, it should be a 5 digit number that starts with a 5
ok, I just looked at the sensor where it taps into the heater and it has psi calibration on it. This is a pressure switch?
hang on I will pull off the control panel cover to check that.
yes, the pressure switch just senses water flow, so we don't need to mess with it, as it will display a FL or flo error if it's the problem. On the board you'll have the pressure switch cable, which we don't need to mess with, then usually right beside it is the hi limit and sensor cables, sometimes both on the same connector.
27101-H is what is printed on the balboa board
its a 2100 system
there was a white label but had the s/n on it and no number starting in 5
I found a plug off the board that goes to a switch on the suction side of the circulating pump. Could that be the problem? This pump was replaced about 5 years ago.
ok,what about the sensors, same connection to the board or two separate ones, many times the sensor cable will have the part number on it on a white label, Balboa usually tags all the parts with numbers.
they are separate plugs
That's the suction switches that they used to put on their spas with the blue boot over it, no, that will throw up a suction error on the topside, which you're not gettting
ok, separate plugs, if it's a Balboa pack it should still have that 5 digit number either on the outside of the control box or more likely on the board itself, usually a white label with a barcode ant the 5 digit number on it. If you don't see that, we may be able to track it off of the white label on the chip in the center of the board.
my bad the plugs are together, was looking at the pressure one next to it.
is the 5 digit number on the wiring diagram? I am looking at it now.
http://www.hottubwarehouse.com/Balboa_Sensor_30337_p/30337.htm ok, the part number you'll need is the balboa 30337 - this is just a random link I pulled up, but you can find them about anywhere. Sometimes the temp sensor is buried in the foam, so you may have to follow the grey wire to the temp sensor when you go to replace the two of them, probably best to do them both at the same time anyway.
it's alright, we won't need it if they're both tethered together, this is the one you need
the temp sensor is buried in the foam.
the other cable goes up and into the back of the heater
yeah, I run into that fun mess about twice a week
I also found a wire severely corroded and burnt slightly
on a relay box on the board
the one on the heater is the high limit, the one in the foam is the temp sensor that's sensing the spa water temperature, it shouldn't be buried too deep in the foam, you can normally just dig it out with a putty knife or flat head screwdriver
it's probably going to one of the two heater relays, that's common on some boards as the heater pulls so many amps, it heats up the wires sometimes if they don't have a great connection. If it's a removable wire, I'd take it out, get a new piece of wire and crimp new ends on it and replace it.
10-4 it looks like I have just enough wire to remake the connector
so i should order the two sensors and replace those first?
yes, they're not very expensive and 90 percent of the time, that's where the problem is, especially if they've never been replaced, normally last around 5-7 years. If you replace them and it still overheats, then we'd need to look at the heater relays on the board to see if something is sticking and keeping it heating when it's not supposed to be. That does happen occassionaly, but not too often, and would require replacing the board itself, so it's always best to try the less expensive fix first, since it's also the most common one as well.
ok, on the black relay box on the board I can see discoloration which is not good
that would cause the whole board to be replaced?
Now when you expose the temp sensor, it may be mounted in a drywell. If it is, you'll see a black nut closest to you, when you loosen that nut up, it will release the seal on the temp sensor, which also means you're going to get wet when you pull it out unless you have someone hole their hand over the inside of the sensor well inside the tub to seal the water off for you while you change it. Remove the o-ring and compression nut from the old sensor assembly and install the nut and then the o-ring back on to the new sensor, insert it and retighten the nut, then you're done, dont' worry about putting foam back on it, it's not necessary.
should wait to do that when I get the sensor pack
I'm guessing the relay you're looking at is labeled either heater or hi limit relay, both of which feed the heating element and do run hot most of the time. Even though it may be discolored on the board, which no, is not a great thing, if either one had broken the solder connection, the spa would not heat at all. So since you're still heating, that's a good thing, but down the road some time you may end up replacing the board, but I wouldn't get in to that until you have to.
should a drywell be dry?
10-4, the spa is still heating
lol, yeah, sorry, if it's a dry well, you can just pull the sensor out, there will not be a large nut threaded on to the backside of the well. If it's a wet well, it will have the nut, which is the most common thing you'll run in to
I normally just have one of my helpers hole their hand over the inside of the spa and it cuts the water off pretty well while you change it. You can actually look down in the spa, if you can visibly see the stainless stell tip of the sensor, then it's a wet well for sure.
I will order the sensor pack and replace them when they get here. How hard is it to get the heater hi limit replaced?
heater or hi limit?
Looks like the heater is bolted to the control panel so that will need to be take loose.
sorry hi limit
the one on the heater itself, the wire goes into a hole on the back of the heater cover/shroud.
if it's the model I think it is, that's mounted to the top of the box and say "Lifetime Warranty" on it, which by the way is useless as they never back them up, then , no, you shouldn't have to remove the heater to replace the high limit, it mounts under a little tab on the heater, you just pull hard and it'll come out, then the new one slides back in the same place, sometimes you have to pry up on the metal tab a bit with a screwdriver to slide the new one back in
ok, its in a pretty hard to access spot but sounds like it will come off with some pulling/ tugging.
once you have the temp sensor exposed from the foam, you should be able to replace the whole assembly in less than ten minutes.
yeah it does say lifetime , ha ha
yeah, not the easiest to get to, but it beats taking the entire heater off
Kewl, thanks much for your help. I think I got it now. Hope this will solve the problem.
yeah, sounds like the temp sensor is the issue, should be an easy fix barring any board problems.