Pentair MasterTemp service code 128 r5

[poolhelp22]

Hi there. I was wondering if one could help me with a MasterTemp start up service code.

Today, when I was trying to run my pool heater, the heater would run until it reached a temperature of about 86, then it would kick an error code (e05) and then stop heating the pool but continue to run. I've had this problem before, and I've fixed it in the past by cleaning the flue sensor. When I went to do this I also decided to blow out the inside of the heater, as there was a lot of debris build up inside the heater itself. When I turned the heater back on, it then read 128, r=5 and then would immediately power off. The blower also did not turn on nor did the heater make any noise. I could smell gas, but nothing was happening. When I took the heater back apart and looked at the control panel, there were no service lights or anything.

Does anyone know what this could be or how to trouble shoot?

 

[ajw22]

Welcome to TFP.

. When I turned the heater back on, it then read 128, r=5 and then would immediately power off.

Normal boot-up is 888, 128, and then rX, where X is the software revision number. Those are not error codes.

The blower also did not turn on nor did the heater make any noise. I could smell gas, but nothing was happening. When I took the heater back apart and looked at the control panel, there were no service lights or anything.

When you blew out the heater, you may have loosened a wire.

Check the wires in the electrical box and connections to the Fenwal module. The Fenwal module is what powers the blower.

Check the wires attached to the PCB.

Read about the startup sequence and blower diagnostics in Pentair MasterTemp Heaters - Further Reading

Next step would have you checking voltages with a multimeter.

 

[JamesW]

When I turned the heater back on, it then read 128, r=5 and then would immediately power off.

R5 is really old.

How old is the heater?

Is it remotely controlled by automation?

Can you show the fireman's switch?

 

[JamesW]

E05(open sensor).

An E06 is a shorted sensor.

If you get a "Service Heater" LED, you will have an error LED on the control board or the Fenwal of the 5 button heaters.

Check the diagnostic LEDs or the Fenwal box LED for blinks.

Diagnostic LEDs are on the back of the older 5-button non-connected Pentair MasterTemp heater board.

The 6 button RS-485 Connected Heater displays the diagnostics on the heater display or IntelliCenter display.

The following are the LEDs:

1. .....PS (Pressure Switch)
2. .....HLS (High Limit Switch)
3. .....SFS (Stack Flue Sensor)
4. .....AFS (Air Flow Switch)
5. .....AGS (Automatic Gas Shutoff).
6. .....Service System
7. .....Thermistor
8. .....Heating
9. .....Pool On
10. ...Spa On
11. ...Service Heater.

 

[JamesW]

I could smell gas, but nothing was happening.

You should not smell gas when the heater is off.

You probably need a qualified gas contractor to check for gas leaks.

 

[JamesW]

I have a Sta-Rite 333K BTU/hr natural gas heater on my pool & spa (2007) and a mouse built a nest over the winter. When I turn on power, the key pad initializes until it displays R=5, then it shuts off.

At start display shows 888 then 128 then R=5

• Jan 14, 2017

It's 10 years old.

Looks like a R5 is from about 2007, which makes it about 17 years old.

 

[JamesW]

May 16, 2015

I just moved to a 8 year old house this past winter with a pool. I just started everything up and fixed a few leaky gaskets and the usual. However, the heater will not start up.

Once power is applied the heater displays 128, then a code across the display is r=5 .

 

[poolhelp22]

R5 is really old.

How old is the heater?

Is it remotely controlled by automation?

Can you show the fireman's switch?

The heater is about 20 years old. It is not remotely controlled. Here is an image of the firemans switch.

 

[poolhelp22]

Welcome to TFP.



Normal boot-up is 888, 128, and then rX, where X is the software revision number. Those are not error codes.



When you blew out the heater, you may have loosened a wire.

Check the wires in the electrical box and connections to the Fenwal module. The Fenwal module is what powers the blower.

Check the wires attached to the PCB.

Read about the startup sequence and blower diagnostics in Pentair MasterTemp Heaters - Further Reading

Next step would have you checking voltages with a multimeter.

Thanks for the help. I checked all of the wires and none of them apear to be detatched or damaged. When I try to start up the heater the blower does not kick on, but there are no leds on the front or back of the control pad indicating that there is an issue. When I look at the fenwal box, the led light does not indicate that there is an issue. Would the next step be checking the voltages or is there anything else I should check?

 

[ajw22]

Did you read Pentair MasterTemp Heaters - Further Reading ?

Blower not Operating​

Listen closely when you turn the heater on after it cycles through the 888, 128, and R13. You may need to put your ear right next to the top of the heater (where the board is) to hear if the small relay on the Fenwal box clicks (May sound more like a "tick" than a "click"), giving voltage to the blower. This click will be more subtle than the click you normally hear when the gas valve opens (you won't hear that one, though, if the blower never starts).

If you can hear the click, look at the blower. If there is no click, look at the Fenwal box. If you are getting the AFS error, the safety switches have been satisfied, and the board should tell the Fenwal module to begin the ignition process.

Another reason the AFS error is thrown is that the airflow switch (AFS) is closed before the blower starts. The Fenwal checks that the AFS is open before it begins the ignition sequence. If the AFS is closed, then the AFS is shown.

The blower is powered through the Fenwal F1/F2 connections that are a relay....