Balboa Spa Pack Tech Question

[dirtrider]

Hello,

Let me first say that I have been on this site many times and have found most of the info I needed (general stuff) and also have learned some things just from passing some time reading here. I would like to thank the folks that "know" these things for sharing with others. I am an Auto Tech by trade, and we do the same on our end. That saying, "What comes around goes around" doesn't always have to be a bad thing.

I have a Master Spa with a Balboa spa controller part # 54493 with a 5.5kw heater with dual heat sensor probes. I am guessing, and from what little info I can find, that the two sensors monitor each other to keep things running. I also figure that there is a differential in temp from the "in" side sensor to the "out" sensor while the heating element is on. My question is, what if the water temp before the element and after the element is the "same temp" while the controller is calling for heat?

To clarify somewhat what I am attempting to do is interupt the "hot" side of my heater element with a double pole double throw switch which I can set to either heat my tub with the electric element, or when the tub calls for heat, it will energize a 24V transformer which in turn will open a 3 way water valve tied into a water to water heat exchanger from an outdoor wood boiler. As the tub heats in this manner, the water temp will rise, but flow through the heater at one temp. I pretty much have everything figured out but need to know about the probes "monitoring" themselves.

OR, does anyone have another way for me to use an outside heat source to heat my tub BUT still use the temp control on the panel on the tub.

Thanks in advance for any replies.

[ttrublue]

I would think 1-prope is temp prope the other hi-limit prope

[ps558]

Hello,

Let me first say that I have been on this site many times and have found most of the info I needed (general stuff) and also have learned some things just from passing some time reading here. I would like to thank the folks that "know" these things for sharing with others. I am an Auto Tech by trade, and we do the same on our end. That saying, "What comes around goes around" doesn't always have to be a bad thing.

I have a Master Spa with a Balboa spa controller part # 54493 with a 5.5kw heater with dual heat sensor probes. I am guessing, and from what little info I can find, that the two sensors monitor each other to keep things running. I also figure that there is a differential in temp from the "in" side sensor to the "out" sensor while the heating element is on. My question is, what if the water temp before the element and after the element is the "same temp" while the controller is calling for heat?

To clarify somewhat what I am attempting to do is interupt the "hot" side of my heater element with a double pole double throw switch which I can set to either heat my tub with the electric element, or when the tub calls for heat, it will energize a 24V transformer which in turn will open a 3 way water valve tied into a water to water heat exchanger from an outdoor wood boiler. As the tub heats in this manner, the water temp will rise, but flow through the heater at one temp. I pretty much have everything figured out but need to know about the probes "monitoring" themselves.

OR, does anyone have another way for me to use an outside heat source to heat my tub BUT still use the temp control on the panel on the tub.

Thanks in advance for any replies.

You have a Balboa M7 style spa pack. The two sensors do everything, water temp, hi limit, protect the heater. The two probes must see no greater temp difference of 3 degrees between them. Otherwise you will get an error message.

Your idea will not work well with the electronic of these packs they design to run the spa and if you tie into the plumbing with extra pipe using the same pump for circulation it will cause a nightmare to control the spa.

My idea would be so add a suction and return line to the spa and have the boiler with its own circulation pump and t-stat. This way the electronics can do the filtering and jet action and the boiler can heat. Set the spa temp to 80 and put in slp mode (sleep) this way it will not heat unless water temp drops to 65. You can use spa suctions and a jet or pool return fitting and the shell can drill out with a hole saw.

[n1oty]

Hello,

Let me first say that I have been on this site many times and have found most of the info I needed (general stuff) and also have learned some things just from passing some time reading here. I would like to thank the folks that "know" these things for sharing with others. I am an Auto Tech by trade, and we do the same on our end. That saying, "What comes around goes around" doesn't always have to be a bad thing.

I have a Master Spa with a Balboa spa controller part # 54493 with a 5.5kw heater with dual heat sensor probes. I am guessing, and from what little info I can find, that the two sensors monitor each other to keep things running. I also figure that there is a differential in temp from the "in" side sensor to the "out" sensor while the heating element is on. My question is, what if the water temp before the element and after the element is the "same temp" while the controller is calling for heat?

To clarify somewhat what I am attempting to do is interupt the "hot" side of my heater element with a double pole double throw switch which I can set to either heat my tub with the electric element, or when the tub calls for heat, it will energize a 24V transformer which in turn will open a 3 way water valve tied into a water to water heat exchanger from an outdoor wood boiler. As the tub heats in this manner, the water temp will rise, but flow through the heater at one temp. I pretty much have everything figured out but need to know about the probes "monitoring" themselves.

OR, does anyone have another way for me to use an outside heat source to heat my tub BUT still use the temp control on the panel on the tub.

Thanks in advance for any replies.

You have a Balboa M7 style spa pack. The two sensors do everything, water temp, hi limit, protect the heater. The two probes must see no greater temp difference of 3 degrees between them. Otherwise you will get an error message.

Your idea will not work well with the electronic of these packs they design to run the spa and if you tie into the plumbing with extra pipe using the same pump for circulation it will cause a nightmare to control the spa.

My idea would be so add a suction and return line to the spa and have the boiler with its own circulation pump and t-stat. This way the electronics can do the filtering and jet action and the boiler can heat. Set the spa temp to 80 and put in slp mode (sleep) this way it will not heat unless water temp drops to 65. You can use spa suctions and a jet or pool return fitting and the shell can drill out with a hole saw.

I concur that the flow rate needs to be maintained or he will have problems. The specs on the M7 packs require a minimum flow rate through the heater (and by the sensors) of at least 25 GPM, at least if the heater element is energized. I suspect that if the heat rise is too rapid, it will probably trigger an error.

John

[dirtrider]

You have a Balboa M7 style spa pack. The two sensors do everything, water temp, hi limit, protect the heater. The two probes must see no greater temp difference of 3 degrees between them. Otherwise you will get an error message.

Your idea will not work well with the electronic of these packs they design to run the spa and if you tie into the plumbing with extra pipe using the same pump for circulation it will cause a nightmare to control the spa.

My idea would be so add a suction and return line to the spa and have the boiler with its own circulation pump and t-stat. This way the electronics can do the filtering and jet action and the boiler can heat. Set the spa temp to 80 and put in slp mode (sleep) this way it will not heat unless water temp drops to 65. You can use spa suctions and a jet or pool return fitting and the shell can drill out with a hole saw.

Thanks for the reply,

OK, a little better description

On my tub, I have what looks to be a 2" (may be larger) line coming from my filters directly to my heater, it comes out of the heater and goes to a pump I haven't pulled that side off, but coming back from that side is a 1 to 1.5" hose going back into my tub which is from the 24/7 circulator pump. This is also where the hot water comes into the tub when the jet pumps are off. The heat exchanger will be just before where it dumps into the tub now. I will not be restricting anything to my heater, or controls, nor any water flow when all pumps and jets are running. The heat exchanger has a flow rate of 44.9 gals a minute so a restricted flow is a non issue. It is also designed for "chemically treated" water. I am very knowledgeable on automotive and equipment hydraulic, electrical AC/DC, spraying, engine, transmission.......systems but I just could find no "technical" info on the probes. I did call where I got the tub, the tech guy was pretty sure that I would be OK but wouldn't give me a definate "yes" answer.

I already know I can heat withn an external heat exchanger (I have already seen one in operation) but it uses an independant thermostat, temp probe, relay, and transformer to operate. I am looking to take that set up one step further and use the existing temp control.

The answer about the probes (my original question) that they should not be affected by NOT (water coming into and out of heater will be "same" temp) seeing a difference between them is the "same" answer I did get from the dealer Tech I spoke with. So, 2 independent same answers is good for me

I going to give a shot. I won't be firing up the OWB till October but I will definately post back how it worked (or not worked )

Thanks again and any other comments are surely welcome.

[n1oty]

You have a Balboa M7 style spa pack. The two sensors do everything, water temp, hi limit, protect the heater. The two probes must see no greater temp difference of 3 degrees between them. Otherwise you will get an error message.

Your idea will not work well with the electronic of these packs they design to run the spa and if you tie into the plumbing with extra pipe using the same pump for circulation it will cause a nightmare to control the spa.

My idea would be so add a suction and return line to the spa and have the boiler with its own circulation pump and t-stat. This way the electronics can do the filtering and jet action and the boiler can heat. Set the spa temp to 80 and put in slp mode (sleep) this way it will not heat unless water temp drops to 65. You can use spa suctions and a jet or pool return fitting and the shell can drill out with a hole saw.

Thanks for the reply,

OK, a little better description

On my tub, I have what looks to be a 2" (may be larger) line coming from my filters directly to my heater, it comes out of the heater and goes to a pump I haven't pulled that side off, but coming back from that side is a 1 to 1.5" hose going back into my tub which is from the 24/7 circulator pump. This is also where the hot water comes into the tub when the jet pumps are off. The heat exchanger will be just before where it dumps into the tub now. I will not be restricting anything to my heater, or controls, nor any water flow when all pumps and jets are running. The heat exchanger has a flow rate of 44.9 gals a minute so a restricted flow is a non issue. It is also designed for "chemically treated" water. I am very knowledgeable on automotive and equipment hydraulic, electrical AC/DC, spraying, engine, transmission.......systems but I just could find no "technical" info on the probes. I did call where I got the tub, the tech guy was pretty sure that I would be OK but wouldn't give me a definate "yes" answer.

I already know I can heat withn an external heat exchanger (I have already seen one in operation) but it uses an independant thermostat, temp probe, relay, and transformer to operate. I am looking to take that set up one step further and use the existing temp control.

The answer about the probes (my original question) that they should not be affected by NOT (water coming into and out of heater will be "same" temp) seeing a difference between them is the "same" answer I did get from the dealer Tech I spoke with. So, 2 independent same answers is good for me

I going to give a shot. I won't be firing up the OWB till October but I will definately post back how it worked (or not worked )

Thanks again and any other comments are surely welcome.

Right, and you can count me as a third yes, provided you examine what I am saying very closely. The firmware in the M7 controllers is more sophisticated than I think you believe. The programming is such that not only do the sensors need to be close in temperature, but the sensors also track rapid heat rise. This is how they "detect" a lack of flow without using a pressure or flow switch. My point is that you must calculate heat rise into your plans or you run the risk of the M7 controller throwing a "dry" error and shutting you down. The firmware is very sensitive to this in these packs, to the point that dirty filters can trigger these types of errors due to the heat rise in the heater tube.

John

[dirtrider]

Right, and you can count me as a third yes, provided you examine what I am saying very closely. The firmware in the M7 controllers is more sophisticated than I think you believe. The programming is such that not only do the sensors need to be close in temperature, but the sensors also track rapid heat rise. This is how they "detect" a lack of flow without using a pressure or flow switch. My point is that you must calculate heat rise into your plans or you run the risk of the M7 controller throwing a "dry" error and shutting you down. The firmware is very sensitive to this in these packs, to the point that dirty filters can trigger these types of errors due to the heat rise in the heater tube.

John

I do believe that they are very sesitive but I am planning (I use that loosely) that the hot water coming out of the heat exchanger, going and mixing with 460 gals of water will not give me a rapid increase in temp of the water after it goes through my filters and back to the heater. (This is how I calculate my rate of heat rise) That's why I am not trying to heat the water before it goes directly into the heater.

That's why in my mind the water entering and leaving the 2 probes, although, slowly rising in temp, will be the "same" temp across both. What I am hoping is that......when my tub is "calling for heat" and probe one, before the element, is reading 100 degree water and probe 2 after the element is also reading 100 degree water..... the controller doesn't say...."hey, my element isn't working" do to NO rise in temp.

Thanks again for your input, it is "greatly" appreciated.

[dirtrider]

Well,

Just in case anyone cares, I have been heating my tub with an external water to water pool and spa heat exhanger and using an outdoor wood boiler for a heat source. It is working flawlessly. It feels nice to know that my tub is being heated for free (well, minus the cutting wood thing ). I use the same controller to heat my tub with either the wood boiler OR the original electric element with an installed 2 pole 2 position switch interupting 1 leg of the heater circuit. In wood mode, all it does is turn on a 24volt transformer (when tub calls for heat) which opens a 3 way valve to circulate the hot water in the exchanger.

Anyway,

Thanks again for the technical "look out for's"