New Mastertemp operating question

nielsens2001

Member
Jun 2, 2011
23
Jersey Shore
Pool Size
16500
Chlorine
Liquid Chlorine
I recently had a new Mastertemp heater installed. In pool mode I’m able to turn heater on, set setpoint temp on ScreenLogic and all works fine. However, in spa mode, I can turn heater on but no matter what I set in ScreenLogic including turning heater off it continues to run until the default temp (104F) on the heater is reached. I have EasyTouch upgrade automation with heater setup using 2 wire. Is this working as expected and do I need the 3 wire setup to independently control the spa temp?
 
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Jimrahbe

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The EasyTouch does not have a three wire system.. I find it odd that the 2-wire system does not work for you.

The heater should not know the difference between the Pool mode and the Spa mode.. All it knows is to heat or not..

The heater should be on and set for max temp. The EasyTouch then looks at the water temp (same temp probe is used for pool and spa) if the water temp is below the set point, then the heater turns on.. When the water temp gets to the set point the heater shuts off.

This is what I get on ScreenLogic using my PC..




Not sure how your heater works, but assume there is some "remote" or "external" mode it needs to be in..

I'll look at the heater manual and see if I can find a clue.

Thanks,

Jim R.
 
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JamesW

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Mar 2, 2011
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I have EasyTouch upgrade automation with heater setup using 2 wire.
Where is the 2 wire connected to?

The heater can be connected by a 2-wire or a 3-wire control.

For a two wire control, you connect to the Fireman’s switch, set the heater to maximum temperature and the automation tells the heater to heat or not heat based on the automation monitoring the temperature of the water. The automation uses a single relay to open or close the fireman’s switch.

For a 3-wire, the automation uses 2 relays to turn on the heater to “Pool” mode or “Spa” mode.

For a 3-wire system. The automation just tells the heater to run in Pool Mode or Spa Mode or off.

For a 3-wire system, the heater uses the set points for Pool or Spa and its own thermistor to heat or not heat.

For a 3-wire system, the automation basically just “pushes” the “Pool On” or “Spa ON” button and you disable the “Pool On” button and the “Spa ON” button at the keypad by moving a jumper.

I suspect that the wire is connected to the three wire connection in the heater instead of the fireman's switch.

4a. To connect a 2-Wire Control (such as Pentair’s IntelliTouch® or EasyTouch® Control

Systems) or a timer:

- Remove the factory installed jumper from the Fireman’s Switch terminals.

- Connect wires between the Fireman’s Switch terminals on the heater and the relay.

Connect wires from the controller or timer to the Fireman’s Switch.

Controller, timer or relay should be sized to handle 24VAC at 0.5 Amp (because it will be completing the 24VAC control board circuit on the heater as shown in Figure 22).

DO NOT apply line voltage to the Fireman’s Switch terminals.

Use 18 gauge wire with a minimum 3/64” (1.2mm) thick insulation rated for a temperature rise of at least 105°C.

- Knock-outs are provided to route the wires through the bottom of the control box and past the junction box.

4b. To connect a 3-Wire Control:

- Connect wires between the control board terminals on the heater and the external relays, as shown in Figure 23.

Use at least 2 relays per heater, to allow for an “OFF setting” on each heater mode.

Select relays that can handle logic level switching.

DO NOT apply line voltage to control board terminals.

- Move jumper (as shown on Figure 23) to enable external control and to disable the heater membrane pad’s “Pool ON” and “Spa ON” buttons (the “OFF” key on the membrane pad remains functional).

- Knock-outs are provided to route the wires through the bottom and the top of the control box and past the junction box.

5. Close control box cover.

 
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nielsens2001

Member
Jun 2, 2011
23
Jersey Shore
Pool Size
16500
Chlorine
Liquid Chlorine
@Jimrahbe & @Jim W thanks for your replies.

Here are pics of the setup. With Spa selected either in EasyTouch or ScreenLogic, heater will not stop when temp set point is reached. It continues heating until 104F default temp on heater is reached. Pool settings, however work fine.
 

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  • Mastertemp Wiring.jpg
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nielsens2001

Member
Jun 2, 2011
23
Jersey Shore
Pool Size
16500
Chlorine
Liquid Chlorine
N,

Just looking for any differences between my ScreenLogic and yours...

Do you have "Spa Heat Manual" checked??? I do...




Going on what JamesW said, I'd unplug the ISR4 remote at the IntelliTouch/EasyTouch main board and see if that makes any difference.

Thanks,

Jim R.
Have unplugged the spa-side controls, still no change.

When Spa valve selected, no call for heat shown on the ET, however Heater still turns on. Makes me think there's something wrong w the board.
 

Jimrahbe

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N,

I believe the way this automation works is that it will call for heat as soon as you go into the spa mode unless "Spa manual heat" is checked...

Could be a bad board, but it works in pool mode, so that is odd.

Jim R.
 

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