Help plan DIY spa control

[Learjeff]

I recently moved into a home with an in-ground spa, about 17 yrs old, in good working order. It has two pumps, one for jets and one for heater. The heater is a new Pentair MasterTemp. The heater and pumps are in an inconvenient location, so we want remote control. In addition, we want the ability to set it to run on a timer, mostly to avoid freezing.

(I understand routine running is also a good idea for circulation to keep water clean, but experience shows that the water stays in great shape without significant flow.)

The heater pump is 1/2HP on 220 VAC, same circuit as the heater. The jets pump is 2HP on a second 220 VAC circuit. The breaker panel is at the pumps, and sits under a roof along with the heater and filter, separate from the house. I want a wireless control in the house; running wires would be a pain.

The MasterTemp has a connector for "fireman" switch, to shut heat off 15 minutes before shutting off the power to the heater. It also allows a connection to switch between "pool" and "spa" temperature.

Basically, what I think I want is
1 control to turn the heater & heater loop pump on/off, with automatic delay on shutoff with fireman switch
1 control to turn the jets pump on and off (more on this in a later post)
Anti freeze protection: either, automatic based on temp sensor, or timer-based, running both pumps and heater

The units I'm looking at are Pentair SunTouch and Intermatic PE15300F (with P1353ME). In either case, I'd need to add two wireless units, the interface at the control center and the remote in the house. Am I barking up the right trees here? I believe that both units mentioned above support a fireman's switch.

For temperature control, I could use the 3rd relay to switch between "pool" and "spa" on the heater. However, I get the impression from reading an installation manual that I can use a temperature sensor, and set the heater to max, and then control the temp from the remote. The only wrinkle to this is that the pump house is a long way from the spa, with a big retaining wall between. I'm not sure where or how I'd run the temp sensor.

I have an electrician I'd have do the serious wiring, and handle the rest myself, so there's no worry about safety and meeting codes.

 

[mas985]

I would stick with a full featured pool controller such as the SunTouch. It has all the features you need including:

Timers

Full Heater Control

Heater Cool Down - Fireman not needed

Value Control

Pump Control - Circulation and Jets

Temperature sensor - BTW, that goes into the piping somewhere before the heater.

Other feature control relays

You might want to read through the manual before deciding:

http://www.pentairpool.com/pdfs/suntouchUG.pdf

 

[Learjeff]

Thanks for the input!

Can you please explain why you don't consider the Intermatic "full-featured"? It has pretty much the same features as the SunTouch, as far as I can tell, except that the remote has far more capabilities.

Can you please explain how the heater cool-down works, if not with a fireman's switch? The heater I have has only two inputs: AC power and fireman's switch. How could the SunTouch cool down the heater, without shutting off the heat via the fireman's switch? Perhaps we're not communicating, most likely because being new to the game I don't quite understand how the terms are really used. I only know what I read in the manuals. (I'm about to study the manuals for the two controllers.)

I've been leaning towards the Intermatic, even though (with wireless) it's 50% more than the SunTouch ($755 vs $510), because the wireless is 2-way, and I'll want to know for sure when we shut off that it's received the signal.

I also don't understand how the unit knows the water temp. The heater knows the water temp from sensors inside the heater. For any other unit to know the temp, I'll need to install a sensor somewhere, and I know nothing about that. I assume I drill into the PVC and insert a sensor and glue it in with a PVC plug or something.

Thanks for explaining about the sensor. That makes sense. No pun intended. I've also learned how the freeze protection works on the Intermatic: when air temp is below freezing, it keeps the pump on (continuously, if I understood what I was told.) Here in NC that would be fine.

This project was on back burner but I'm about ready to order the parts.

Thanks again!

 

[mas985]

The Intermatic is only a timer. It turns the pump on and off and that's it.

Suntouch is also a timer but much more. Here is a list of some of the features:

Full heater control including automatic cool down and temperature setting
Solar valve control
Pool/Spa valve control
Temperature readout of water, air and solar
SWG support
Freeze protection
VS pump support
Wireless remote control

No comparison in my mind.

The way the heater cool down works in the Suntouch is if the pump is scheduled to turn off or you try to turn the pump off manually, this action is delay 10 minutes so the heater can cool down. You can override that if you want to but normal operation is that the controller will not turn off the pump immediately if the heater has been running.

I've been leaning towards the Intermatic, even though (with wireless) it's 50% more than the SunTouch ($755 vs $510), because the wireless is 2-way, and I'll want to know for sure when we shut off that it's received the signal.

The wireless remote for the Suntouch does that as well.

I also don't understand how the unit knows the water temp. The heater knows the water temp from sensors inside the heater. For any other unit to know the temp, I'll need to install a sensor somewhere, and I know nothing about that. I assume I drill into the PVC and insert a sensor and glue it in with a PVC plug or something.

A water temperature sensor that is installed in the plumbing. It is a compression fitting with a gasket so no glue is required.

You might want to read through the documentation before making your choice:

http://www.pentairpool.com/pdfs/suntouchDS.pdf
http://www.pentairpool.com/pdfs/suntouchUG.pdf

 

[Learjeff]

Thanks again. There's a huge difference in quality in the manuals; the SunTouch is far better. The two have many features in common, and I have no need for many of the features you mentioned, since I have a single body of water, no solar, and no valves. The Intematic doesn't have a water temp sensor, so if I want to control water temp I need the SunTouch. Unfortunately, though, the SunTouch remote won't control the water temperature (other than heater on/off and a temporary "heat boost"), so I'm not sure why I'd need the control center to control the temperature. But, I can see using this for a much lower temp cycle every night, instead of the usual freeze protection.

Regarding the fireman's switch, that's what either unit uses to control the gas heater (to do cooldown). We must just have miscommunicated on that. It's J12 on the Suntouch, which connects to the fireman's switch on the heater.

You explained the sensor earlier, and I edited my post but for some reason the edit didn't appear. That's clear, thanks.

Regarding the remote. The pumphouse is a good distance from the spa, on the other side of a stone retaining wall, around the corner of the house, and a floor below (thus wanting the remote!) I'm not certain that the signal will always make it. How can one tell whether the signal was received? As far as I can see, the remote is just a button box with no display other than a "transmit" light. When turning it on, no worries: you can immediately tell if it worked. But when turning it off, if the heater isn't burning at the moment, you won't notice any difference (because the pump will continue running for a short time). I guess we could turn an accessory on and off to make sure it's responding. Fortunately we can hear the heater kick in from our bedroom, so maybe this isn't a deal killer.

In any case, I totally missed the big detail that the Intermatic doesn't have a temperature sensor, and that makes its better remote a lot less useful. (Its remote has full control and programming capability; it's not just a button box. Furthermore, it floats, and the QT4 doesn't. But that can be fixed by keeping the QT4 in a ziplock bag!)

So, I really appreciate your feedback, and the SunTouch is what I think I'll go for, despite its lesser remote.

One last question. My wife wonders why I'm planning to keep the electrical sub-panel (with two 220 circuits and one 110), thinking that the SunTouch should replace that. My understanding is that it does not: I still need to bring the 220 from the house panel into a panel that separates circuits for the various loads. (Plus I might replace the breakers with GFCBs.) But am I being redundant here? Could I do all the wiring with just the SunTouch? The manual says I should have an additional breaker for the pumps, but downstream of the SunTouch. I'd probably want to keep them upstream for simplicity in wiring.

I hope that's the last question. Well, it's the last for now!

 

[mas985]

If you look on page 44 of the manual, you can see that the Suntouch has breakers and power connections so technically a sub panel is not required. However, local codes may require it anyway so you might want to check on that.

 

[Learjeff]

Those are low voltage breakers. Regardless, I see drawings that clearly show a breaker panel with two feeds for different pump circuits, so I'll keep the panel. Plus I want to keep the 120 circuit, which feeds standard outlets in the pumphouse, in case I need a light or a power tool or whatever.

Thanks again.