So I’m trying to troubleshoot my heater, ever since we bought the house a couple of months ago it has not functioned correctly. It has the normal boot up with 888, 128, then r 13. Right after it turns on and the display shows service system LED on. I have disassembled the heater and took a picture of the PS led on. I did attempt to bypass the PS, it didn’t work but I may be doing something wrong, got an old piece of 12 guage wire and attempted to connect the two purple wires. No change in the lights. I did notice it looks like the purple wire has been melted and crimped on one of the two so I suspect it might be that? If anyone can think of anything I can test before snipping the purple at the bad spot and reconnecting the wire please let me know.
Pentair Max-E-Therm 400 PS LED and Service Heater LED On
- Thread starter bobbywebster22
- Start date
The following are the LEDs:
- .....PS (Pressure Switch)
- .....HLS (High Limit Switch)
- .....SFS (Stack Flue Sensor)
- .....AFS (Air Flow Switch)
- .....AGS (Automatic Gas Shutoff).
- .....Service System
- .....Thermistor
- .....Heating
- .....Pool On
- ...Spa On
- ...Service Heater.
Much appreciated, I only notice the PS led on so I’ll attempt to fix the wire and bypass to see if it’s the pressure switch that needs to be replaced. I appreciate the help!
Following up, I cut off the bad part of the wire and crimped on a new female fitting, used a section of 16 AWG that I crimped on two male fittings to and the PS led is still on and the service system light is still on, any recommendations?
PS + "Service System" means the pressure switch is working as it should and your system, pump/filter, isn't. Most commonly a very dirty filter not allowing enough waterflow to close the pressure switch and let the heater fire. Or a clogged basket in the pump or skimmer, or a clogged suction line as we go from bad to worse.
As they say, "Don't kill the messenger."
So I thought that as well and went ahead and backwashed the filter before I did anything. I can see the stem on the PS raise all the way up and the switch on the bottom is engaged. I will attached photos for reference. I have been reading a few other posts and some people found success after replacing the PCB but I’ll keep testing things before purchasing anything new.
Attachments
also not sure if this changes anything, but when I turn on the heater and the service light comes on I can’t do anything else with the buttons, moving temp up or down does nothing and turning pool on does nothing. Only button that seems to work on the controller is the heater off button. Otherwise it’s like it’s locked.
James/1poolman1,
What a nightmare this is turning into, I disconnected the control board, took some isopropyl alcohol and a small toothbrush and lightly removed any residue on all connections and solder points. Reconnected the control board and fired it back up, and guess what the PS sensor is gone, however I didn’t get to celebrate for long. Now the service heater light is on, the membrane pad did work momentarily then I got an EO1 error, ordered a thermistor it will be here tomorrow $12 fortunately. Then turned it off and back on and now I don’t get an EO1 error at all but the service heater light is on and the AFS light is now on. At this point I’m concerned that the control board is just malfunctioning so I ordered a replacement board and membrane pad and that will also be here tomorrow. Hopefully I will see some good results from this. If not I’ll replace the air flow switch and go from there.
What a nightmare this is turning into, I disconnected the control board, took some isopropyl alcohol and a small toothbrush and lightly removed any residue on all connections and solder points. Reconnected the control board and fired it back up, and guess what the PS sensor is gone, however I didn’t get to celebrate for long. Now the service heater light is on, the membrane pad did work momentarily then I got an EO1 error, ordered a thermistor it will be here tomorrow $12 fortunately. Then turned it off and back on and now I don’t get an EO1 error at all but the service heater light is on and the AFS light is now on. At this point I’m concerned that the control board is just malfunctioning so I ordered a replacement board and membrane pad and that will also be here tomorrow. Hopefully I will see some good results from this. If not I’ll replace the air flow switch and go from there.
@JamesW update and questions for you, replaced the PCB and Thermistor. The unit finally kicks on and says it’s heating but after about 5 minutes the blower shuts off and it just says heating but I haven’t seen the temperature go up, is that normal? No other lights or errors showing up on the PCB. It’s been 10 minutes and I haven’t seen the temperature go up at all and the display is frozen and won’t let me adjust temperature up or down.
Attachments
It says "Heating", but it is not heating?
Does it display an error?
Check the Stack Flue temperature while running.
Check the Flame Current.
Check the Fenwal for LED error lights.
Pentair MasterTemp Heaters - Further Reading
www.troublefreepool.com
Heater Flame Sensing - Further Reading
www.troublefreepool.com
The heater looks pretty old.
It might be time to consider replacing it.
Can you find a date on the heater to tell how old it is?
You can also check the gas pressure static and dynamic to see if that is good.
In the below video, you can see that the static pressure (Heater Off) was good but the dynamic gas pressure (Heater On) was bad indicating a restricted gas line.
It might be time to consider replacing it.
Can you find a date on the heater to tell how old it is?
You can also check the gas pressure static and dynamic to see if that is good.
In the below video, you can see that the static pressure (Heater Off) was good but the dynamic gas pressure (Heater On) was bad indicating a restricted gas line.
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Well you have me in the right track, took the cover off (never thought to check that as I didn’t see anything yesterday) now after running for about 2 minutes I get three flashing lights which according to what you sent me means no flame current being sensed and ignition locked out.It says "Heating", but it is not heating?
Does it display an error?
Check the Stack Flue temperature while running.
Check the Flame Current.
Check the Fenwal for LED error lights.
View attachment 613049
Pentair MasterTemp Heaters - Further Reading
Heater Flame Sensing - Further Reading
@JamesW I appreciate all of your help and wanted to give you an update. I got it up and running. After the ignition lockout I replaced the igniter and still couldn’t get it to work, decided to try some other options and landed on bypassing the combination gas valve. Once I did that it fired right up and has been working flawlessly since. I ordered a replacement one off eBay but some people from other forums have had it bypassed for years with no issues. Just wanted to give you an update and say I appreciated the assistance.
For anyone else that may come across this with a similar issue here are some other things I replaced working through each of the errors I received until I got it up and running. The things that I replaced were the PCB, replaced two membrane pads, Thermistor, Flue Stack Sensor, and Ignitor. I’ve attached a video I found where someone had the same issue as me and bypassed the gas valve.
For anyone else that may come across this with a similar issue here are some other things I replaced working through each of the errors I received until I got it up and running. The things that I replaced were the PCB, replaced two membrane pads, Thermistor, Flue Stack Sensor, and Ignitor. I’ve attached a video I found where someone had the same issue as me and bypassed the gas valve.
Pentair Mastertemp 400 - No Ignition, No Error lights, tested a few things and need help.
Well it's been a few years since I was back on the TFP. Because my pool(s) have been trouble free after learning so much! However, I have been working on my Pentair Mastertemp 400 for about a day now - between research and video's and trying to troubleshoot what's actually wrong before I start...
www.troublefreepool.com
I’m impressed you found that so fastPentair Mastertemp 400 - No Ignition, No Error lights, tested a few things and need help.
Well it's been a few years since I was back on the TFP. Because my pool(s) have been trouble free after learning so much! However, I have been working on my Pentair Mastertemp 400 for about a day now - between research and video's and trying to troubleshoot what's actually wrong before I start...