Sta-Rite Max-E-Therm Will Not Light No Error Codes

Jump to latest Follow Reply
In the further reading that Allen referenced look for the method to add a ground wire between the burner and the ground wire on the controls panel. Sounds to me that you may have poor ground connections that interferes with flame rectification. This is a fairly common failure in older flame rectification controlled heaters and it's very easy to add the ground wire. The unit detects flame by passing a tiny signal from a flame sense rod (or the igniter itself if you don't have a separate flame sense rod) through to the burner and this must be detected by the ICM in order to open the gas valve. The current that passes is only a few millionths of an amp so it's easily interfered by corrosion anywhere in the ground. If your ICM is a Fenwal do you see a red light that is flashing? How many flashes do you see?

I hope this helps.

Chris
 
jamescodling said:
Thank you Chris! I get the three flashes which happened on both the old Fenwal and the new one I put in.
Click to expand...

With 3 flashes you very likely do have a flame rectification issue. This can be due to:
  • Igniter failure
  • Ignition control module failure
  • bad sensor connection(s)
  • bad wire, especially with rodents that eat wire insulation
  • poor ground
  • damaged ground in the power supply to your heater often caused by lightning strike or direct short in the wiring
Sounds to me that you've ruled out the first 4. So I'd run the ground from your flame tube that's described in Allen's reference. The wire must contact the flame tube not just go from a flange bolt. Next thing I'd do is to run an independent power supply wire from your breaker to the heater power connection. Before you start be sure to check your gas supply. It's amazing how often people miss a gas valve that's been closed unintentionally in the off season. Always check the simple stuff first!

I hope this helps.

Chris
 
It doesn't make sense to chase down flame rectification if you know that there's no flame.

The purpose of flame rectification is to prove that there is a flame when there should be a flame.

Since we know that there's no flame, the flame rectification is doing the right thing by shutting down the heater.

If we can establish that the igniter is good and using the correct amount of power, then it points to a gas issue.

If you have enough gas and a red hot igniter, you're going to get ignition and a flame.

If we know that there's a flame and the flame rectification is still shutting down the gas valve, that's when you investigate flame rectification.
 
JamesW said:
It doesn't make sense to chase down flame rectification if you know that there's no flame.

The purpose of flame rectification is to prove that there is a flame when there should be a flame.

Since we know that there's no flame, the flame rectification is doing the right thing by shutting down the heater.

If we can establish that the igniter is good and using the correct amount of power, then it points to a gas issue.

If you have enough gas and a red hot igniter, you're going to get ignition and a flame.

If we know that there's a flame and the flame rectification is still shutting down the gas valve, that's when you investigate flame rectification.
Click to expand...
Whoops, I thought he'd replaced the igniter. Maybe I got posts mixed up. Definitely do as Jame suggests first. Do you have a glass window to check the window for red glow on igniter? You could even power the igniter and check for glow. Should start with light glow then build to bright orange. Gas supply or gas valve would be my next stop in this case too!

Chris
 
Just to add to my previous post. Flame rectification problems can only be the problem if your heater is going all the way to igniting and then turns off. You'll know this by the sound of the flame, a short burst of heat in the exhaust, and a brief gas odor. If you don't have this you have a different problem.
 
I've got my work cut out today for sure ! I can't see how it's a gas issue as nothing on that end has changed. I did take it all apart and check orifice, etc. There is definately gas there and it's a direct line tot he meter. I really appreciate the tips guys, more to come!
 
In keeping with "always try the simple stuff first"

  • Wiggle the connectors at each of the safety sensors. This will often cause a "check ign error". If this makes a change clean and reconect
  • Do Check gas pressure at the unit. Easiest place to do this is at the cap on the end of the debris trap if you don't have a better place.
As easy as it is to check these, It's amazing how often these two issues are not checked and end up being the problem after many hours and $ spent. The first item was my issue for the very same error code on a very new heater and after fixing, coating with Corrosion Block never occurred again.
 
I looked at what I believe is your heater manual: https://www.questargas.com/ForEmplo...ning/Boilers/Pentair_STA-RITE_MAX-E-THERM.pdf and it is of a similar design as setsailsoon's in that it mixes both combustion air and gas before entering the combustion chamber. This design has been tried and abandoned in several residential and commercial furnaces because of inherent problems. It uses a negative pressure gas valve and can be picky as to the combustion air/ gas mixture ratio, which can effect the ability to light off. I would first ohm out the ignitor (silicon carbide ), it should be 45 ohms to ~ under 400 ohms cold ( if it reads 0 ohms it is open and is no good). When power is applied to a good ignitor it should draw about ~ 4-5 amps as it heating up . If the ohm and amp readings for the ignitor are both good, I would look to a problem with the gas/air path or gas/ air mixture ratio. You would need the correct meters ( multimeter and/or clamp on/series ammeter & manometer ) in order to check these parameters (setsailsoon purchased these in order to check his heater). One difference that I see between your heater and setsailsoons is that his uses a metal screen in the combustion chamber before lighting off the gas/air mixture and yours appears to fire directly without a screen for mixture/dispersion. Will be happy to help with any other questions.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Put the gas system back together this morning and did a test run. The new igniter is definately getting hot. At the base it's hot enough to burn. I could not tell whether there was flame or not but it didn't appear to be a puff of heat so at this point I am assuming there wasn't ignition. I did smell the small amount of gas. I'll check connectors on all the sensors as well.
 
swamprat69 said:
I looked at what I believe is your heater manual: https://www.questargas.com/ForEmplo...ning/Boilers/Pentair_STA-RITE_MAX-E-THERM.pdf and it is of a similar design as setsailsoon's in that it mixes both combustion air and gas before entering the combustion chamber. This design has been tried and abandoned in several residential and commercial furnaces because of inherent problems. It uses a negative pressure gas valve and can be picky as to the combustion air/ gas mixture ratio, which can effect the ability to light off. I would first ohm out the ignitor (silicon carbide ), it should be 45 ohms to ~ under 400 ohms cold ( if it reads 0 ohms it is open and is no good). When power is applied to a good ignitor it should draw about ~ 4-5 amps as it heating up . If the ohm and amp readings for the ignitor are both good, I would look to a problem with the gas/air path or gas/ air mixture ratio. You would need the correct meters ( multimeter and/or clamp on/series ammeter & manometer ) in order to check these parameters (setsailsoon purchased these in order to check his heater). One difference that I see between your heater and setsailsoons is that his uses a metal screen in the combustion chamber before lighting off the gas/air mixture and yours appears to fire directly without a screen for mixture/dispersion. Will be happy to help with any other questions.
Click to expand...
Swamp,

Thanks for chiming in, I should have called you in as you were so helpful in my previous heater problems. One question when you mention metal screen are you talking about the part inside the flame holder (#11)? Mine did not have this. Only the flame tube and the igniter was in a separate opening beside the flame tube mounted a few inches away in the lid. The more I look at this it definitely looks a lot different from mine. Not sure if this makes any difference in the diagnosis or fix. Just want to learn the max I can from you.

Chris
 
If the igniter is getting hot, it points to a gas supply problem.

If you have a hot igniter and enough gas, you're going to have ignition.

Is the switch on the heater gas valve On?

Is the gas valve just outside the heater On?

Is the gas valve by the meter On?
 
Yes, gas is on all the way back to meter.. I pulled apart the unions yesterday and confirmed gas. I had a 0-15psi gauge I put on the end since I didn' t have a manometer and it blipped a 1/4 PSI or so. All gas is definately on. Is it possible the blower has junk in it that is messing with the fuel mix? That's the only other thing I can think of at this point. I rechecked all the grounds, no corrosion and no loose connections. And thanks everyone for the help.
 
If you had mice, they might have built a nest in the blower, but that would usually cause an AFS LED.

Have you confirmed voltage going to the gas valve?

Have you confirmed voltage and current going to the igniter?

It might be a bad gas valve.

Maybe some pictures or video will help with diagnosis.
 
This sounds very close to the issue I had with my Max-e-therm. Everything checks out diagnostically except for the ignition lockout on the fenwall, yes. And, It seems you have troubleshot everything except the gas valve itself. Have you checked to see if you are getting gas on downstream side of the gas valve? In my case it was the coil on the regulator side of the valve had failed. I will always defer to JamesW... he has far more experiencing looking at these things than I ever will, I just want to relate what I found in my case.
 
mguzzy said:
This sounds very close to the issue I had with my Max-e-therm. Everything checks out diagnostically except for the ignition lockout on the fenwall, yes. And, It seems you have troubleshot everything except the gas valve itself. Have you checked to see if you are getting gas on downstream side of the gas valve? In my case it was the coil on the regulator side of the valve had failed. I will always defer to JamesW... he has far more experiencing looking at these things than I ever will, I just want to relate what I found in my case.
Click to expand...
I can smell gas which tells me gas is making it through the valve and out the vent by force of the blower. I can't see how I would be able to smell gas if the valve wasnt opening? Thoughts?
 
Last edited:

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply