New Intellicenter Gas Heater Terminals Always On

[treyrich]

Hi, I have a brand new build and yesterday started trying to get the heater (MasterTemp 400HD) working for the first time. Everything appeared to work great, I set a desired heat mode to the gas heater and set the desired pool temperature in intellicenter and the heater fired right up. It ran for several hours, then I decided to try it out on the spa, so I switched it over to spa mode and set a desired temperature there. The heater heated up to the desired spa temperature and then held it (turning on and off as expected). Then things got strange.

I switched it back to pool mode and the heater ran until it hit the desired temperature, then it turned off for 27 minutes (have been logging the state of things via njsPC), then the heater came on for 12 minutes, then it shut off. I figured all was well and I went to bed assuming that the heater would hold the temp over night with the pool covered. When I woke up the pool was 93°! And the heater was running nonstop. According to intellicenter (and njsPC) the heater was 'off', however the heater was very much running but with the pump only running at the non-heater speed so it was cycling on and off constantly (presumably because of lack of flow). I turned the heater off via it's own "heater off" button.

Upon further investigation I have found that the Gas Heater Terminals, for use with the firemans switch on the heater, are putting out a constant 24v so long as the intellicenter is in either pool or spa mode (regardless of the heat source, set temperature, or speed of pump). If I turn off both pool and spa mode then the voltage drops to 0, but so long as some mode is enabled intellicenter is telling the heater to run.

I'm completely new to pool equipment, but have a fairly extensive background in DIY wiring and electrical work, and am a professional software engineer not shy around software or diagnosing/isolating issues. It seems clear to me that the issue is on the intellicenter side and not the mastertemp side. What is unclear to me is whether this is a hardware issue, or a software misconfiguration that I somehow missed. I assume that if it's a hardware issue then the best course of action is to talk to pentair for warranty service, but before I go down that road I wanted to get the experts here to give an opinion in case I am missing something.

One additional step I've considering is moving the control from the firemans switch to the RS485 control. Obviously that doesn't solve the problem if there is one, but I assume that would restore predictable functionality to the system (and may be a preferable method of integration anyways? Still unclear which method of connection is the preferred/best practice).

Thanks in advance for any help.

 

[Ahultin]

What water temp is the ic sensor reading? What max temp is the heater set to?
My install is approaching a yr old and setup via rs485. The biggest advantage is mastertemp error reporting thru intellicenter

 

[ajw22]

.Upon further investigation I have found that the Gas Heater Terminals, for use with the firemans switch on the heater, are putting out a constant 24v so long as the intellicenter is in either pool or spa mode (regardless of the heat source, set temperature, or speed of pump). If I turn off both pool and spa mode then the voltage drops to 0, but so long as some mode is enabled intellicenter is telling the heater to run.

The gas heater relay does not put out 24V. The relay is a simple SPST relay that opens or closes the circuit.

The 24V comes from the heater control loop and the IntelliCenter Gas Heater relay simply completes the 24v circuit to power or unpower the heater.

Since the relay does open to depower the 24V heater loop the IntelliCenter and relay is working.

You have something programmed wrong in the IntelliCenter or nodejs control that is telling the IC to keep the heater running.

Change your heater control to RS-485. Although if the IC is commanding heat it will likely run the heater with the RS-485 control also.

 

[ajw22]

What version IntelliCenter software are you running? 1.064 or 1.232?

 

[treyrich]

What water temp is the ic sensor reading? What max temp is the heater set to?
My install is approaching a yr old and setup via rs485. The biggest advantage is mastertemp error reporting thru intellicenter

IC is reading 93°, set point is 85°

The gas heater relay does not put out 24V. The relay is a simple SPST relay that opens or closes the circuit.

The 24V comes from the heater control loop and the IntelliCenter Gas Heater relay simply completes the 24v circuit to power or unpower the heater.

Since the relay does open to depower the 24V heater loop the IntelliCenter and relay is working.

You have something programmed wrong in the IntelliCenter or nodejs control that is telling the IC to keep the heater running.

Change your heater control to RS-485. Although if the IC is commanding heat it will likely run the heater with the RS-485 control also.

Wouldn’t the IC or njspc report that the heater was running though if it were sending the instruction to run? Both report the heater is in the off state when it’s still running.

What version IntelliCenter software are you running? 1.064 or 1.232?

1.064

 

[treyrich]

What water temp is the ic sensor reading? What max temp is the heater set to?
My install is approaching a yr old and setup via rs485. The biggest advantage is mastertemp error reporting thru intellicenter

Sorry, max temp is 104°

Also, failed to thank you @ajw22 for your added explanation of how the relay works on the IC, that is very helpful. However I do still believe that there is an issue with the IC closing that circuit when it shouldn’t be.

 

[ajw22]

IWouldn’t the IC or njspc report that the heater was running though if it were sending the instruction to run? Both report the heater is in the off state when it’s still running.

Are you seeing the on the OCP, ICP, or app?

 

[treyrich]

Are you seeing the on the OCP, ICP, or app?

Not sure what OCP is, but assuming ICP is intellicenter panel? On the IC touch screen, the IC App (mobile and web), njsPC dashboard and API all report the heater is “off” when it’s actually running. What’s further, IC drops the pump down to my slow speed (believing the heater is not running) which is too slow for the heater and causes the heater to go crazy with the flow switch constantly toggling on and off.

 

[ajw22]

OCP = Outdoor Control Panel
ICP = Indoor Control Panel

Maybe the gas heater relay is sticking on. Make a warranty claim with Pentair.

If it is physical relay problem then changing to RS-485 control should resolve it.

 

[Ahultin]

Given Simplest explanations often win and brand new hardware, I would check for abrasions in the cable going to the firemans switch. Any unintended contact of the two conductors could cause the behavior you are describing, As I understand, when there is no flow (pool/spa circuit off) the flow switch in the mastertemp would turn the heater off.

 

[ajw22]

Given Simplest explanations often win and brand new hardware, I would check for abrasions in the cable going to the firemans switch. Any unintended contact of the two conductors could cause the behavior you are describing,

To that point. When the heater is running and the IntelliCenter thinks it is off disconnect the firemans switch control wire at the gas heater relay. If it continues to run then it is a wire problem.

You can do a lot of diagnostics using a multimeter and checking continuity if the relay properly opens and closes and if there is an open or short circuit between the control wires.

Check for any strands of the wire sticking out of any of the connectors.

And the MasterTemp Installation Manual specifies to use 18 gauge wire with a minimum 3/64” (1.2mm) thick insulation rated for a temperature rise of at least 105°C. The area the wire passes through can get hot and melt wire insulation.

As I understand, when there is no flow (pool/spa circuit off) the flow switch in the mastertemp would turn the heater off.

The MasterTemp uses a pressure switch, not a flow switch. Depending on the heater installation conditions a pressure switch can stay engaged with no flow.

 

[treyrich]

OCP = Outdoor Control Panel
ICP = Indoor Control Panel

Thanks for that. I don't have an indoor control panel, so I'm only referencing the outdoor one and the various apps.

Maybe the gas heater relay is sticking on. Make a warranty claim with Pentair.

My pool builder said that the pentair warranty guy should come around in the next couple of days to take a look at it, so I'm already semi-down this path.

To that point. When the heater is running and the IntelliCenter thinks it is off disconnect the firemans switch control wire at the gas heater relay. If it continues to run then it is a wire problem.

Great idea, I will give this a shot.

 

[treyrich]

Ok. Don't have a ton of confirmation yet because I haven't had a chance to use the heater. But the Pentair guy said that the person who setup the system configured the heater as the wrong type in the system and that's what was causing the issue. I'll assume he was right for now until I get a chance to test it all out.

 

[Poolbreh]

You have something programmed wrong in the IntelliCenter or nodejs control that is telling the IC to keep the heater running.

 

[treyrich]

Just to close the loop here, it does appear that the misconfigured heater was the issue.

Now, to clarify everyone’s opinion. It sounds like the RS-485 connection is good, is it worth me switching to? The pentair guy today said he thought it was more trouble than anything and that I should keep to the firemans switch.

 

[ajw22]

For folks who encounter this problem what was the heater type set to that was incorrect?

Using the RS-485 will show heater diagnostic and other messages on the IntelliCenter displays.

It is a more complex control interface than the fireman’s switch since it shares the RS-485 bus with other devices - pumps, SWG, etc. Many techs don’t know how to diagnose a RS-485 comm problem.

 

[treyrich]

For folks who encounter this problem what was the heater type set to that was incorrect?

It was set to “connected heater” I believe, I should have taken a screenshot because I don’t remember well. It might have been “mastertemp”, but I’m reasonably certain it was something more generic like “connected heater”.

 

[ajw22]

Ok, connected heater implies using the RS-485 interface for the MasterTemp and not the heater relay.

Interesting how the IntelliCenter handled the wrong configuration.

 

[treyrich]

Yeah...I mean I wasn't the one that set it up initially, so I guess my assumption that it was setup properly was where I went wrong. But it does seem odd. The oddest part is that the pool was running for weeks with no heater at all just fine, then when I turned on the heater it fired up like expected, but then there was no turning it off after that. Definitely odd in the way that it reacted, but glad that the tech knew how to solve it quickly.

 

[ajw22]

Pentair has had its challenges with the IntelliCenter software quality. It has its bugs and is quirky. In spite of that I think it is the best from the major pool companies.