Max E-Therm SR400HD Error Code E06

[maiden rules]

Hi Guys,

I know this topics been discussed many times and I've ready those posts but my situation seems a little different so I wanted to start a new thread.

Bought my current home 4 years ago and the heater came with it. It's worked fine for 3 years. I've had to replace some wires that were chewed by presumably a chipmunk or one of my dogs each year the same wires get chewed and I fix them and everything works. This time that was not the case. Pump has error code E06 for fault in the stack flu sensor. Control board is old style on top. Service heater light is on. Under side of the control board has SFS light illuminated. I shut off the breaker and flip it back on and same thing. I pulled fireman fuse and the same code appears. I ordered a stack flu sensor, turned breaker off, replaced sensor, turned breaker back on and no change. The heater will not turn on at all. None of the buttons on the control panel work. It just displays E06 and the service heater light stays on. I checked the stack flu for blockage and it's clear. I checked all wires and they look good, nothing chewed. Could it be that the SFS I bought is just a bad one? What else can I do to troubleshoot this issue?

 

[ajw22]

Welcome to TFP.

Did you buy a generic SFS or a Pentair OEM?

The sensor can be tested with an ohm meter (3.8 MegOhms @ 77F)

If you have a 3.8 MegOhm resistor connected to the heater SFS terminal, it should read 77 degrees from the control panel. Get a 3.5 to 3.8 ohm resistor and connect it to the SFS wires to see what the SFS temp is with the resistor. You can use several resisters in series to create the correct resistance. For example, (3) 1.2 MOhm resistors in series creates 3.6 MOhm of resistance.

Do not operate the heater without a correct SFS sensor.

The above is only to test while the heater is not running.

 

[maiden rules]

I bought a generic SFS not a OEM Pentair. I'll try the ohm resistor method and see what temp is being read. If that reads 77 degrees then my control board is good right? If it reads 0 that would mean its bad?

 

[maiden rules]

Can you provide some guidance or a link to where I can buy an ohm resistor?

 

[ajw22]

Can you provide some guidance or a link to where I can buy an ohm resistor?

Amazon

 

[maiden rules]

I have no idea what I'm buying though. What I searched came up with this: https://www.amazon.com/Projects-100...refix=3.5-3.8+megaohm+resistor,aps,148&sr=8-7

is this what I need?

 

[ajw22]

I have no idea what I'm buying though. What I searched came up with this: https://www.amazon.com/Projects-100EP5123K60-3-6k-Resistors-Pack/dp/B0185FIUI0/ref=sr_1_7?crid=3JUE7L9J4FHX&dib=eyJ2IjoiMSJ9.hImW3Djr0fOXGZv-L4NcLtn9-bNwyIktcjojIKS9Jn4p-uh-lwMF5ZvLTyGSvC1VazTYO_pFDA4P5tBfziibmhKGsS0jBcFZ30ET6IkrVh35o1iDK3SJohGEWVV8UA6JS4xHrrnnZn_xK6n4Z2s-twEQxDeEnqZp0vgUIAEjF5LO-8wGptHSJbUHRoY-N_bmoG7exs8-wTZPC4vOhrGB-gy5IVzEVvnc9FERuRVfNik.3790WztOhyBISN1wjAwXEQU49On2AmtEATsvYnlGFH4&dib_tag=se&keywords=3.5-3.8+megaohm+resistor&qid=1717695842&sprefix=3.5-3.8+megaohm+resistor,aps,148&sr=8-7

is this what I need?

That will work.

 

[JamesW]

(3) 1 MOhms + (8) 100 kOhms resistors = 3.8 MOhms of resistance.

https://www.digikey.com/en/products/detail/yageo/MFR-25FTE52-1M/13921149

https://www.digikey.com/en/products/detail/yageo/MFR-25FTF52-100K/13921107

 

[JamesW]

Any combination in series that adds up to 3.8 Mohm.

3.74 Mohm + 100 Kohm = 3.84 Mohm.

3.4 MOhms + (4) 100 Kohm = 3.8 Mohm.

https://www.digikey.com/en/products/detail/yageo/MFR-25FBF52-3M74/9138163

https://www.digikey.com/en/products/detail/yageo/MFR-25FBF52-3M4/9138158

https://www.digikey.com/en/products/detail/yageo/MFR-25FRF52-1M2/13921868

https://www.digikey.com/en/products/detail/yageo/MFR-25FBF52-2M/9138111

 

[JamesW]

3.6k Ohm Resistors won't work, because you would need 1,056 in series.

1,056 x 3,600 ohm = 3,801,600 ohm.

 

[ajw22]

That will work.

Sorry, I misread that on my phone as MegaOhms. That will not work.

 

[maiden rules]

Other than an Ohm resistor tester (I don't know how to use one). How else can I tell if its the SFS itself (aftermarket one maybe is junk) or the control board?

 

[ajw22]

Other than an Ohm resistor tester (I don't know how to use one). How else can I tell if its the SFS itself (aftermarket one maybe is junk) or the control board?

You can't.

The circuit runs using resistance ohms as its indicator.

Learn how to use a multimeter to check resistance or find someone who can.