Another.....Mastertemp 400 with AGS LED + Service Heater LED
- Thread starter Kihon
- Start date
Not sure, pool and spa heating working perfectly fine since I did this Jan 14, 2020. Never replaced the board. Do you know?
I'm not sure what it goes to.
It's not safe to jumper any control like that.
You are forcing something on continuously.
It's not safe to jumper any control like that.
You are forcing something on continuously.
This is not safe and it is not something anyone should do.
Bypassing any heater control is a serious safety hazard.
My recommendation is to replace the board and not run the heater like it is.
Yes, of course I know and others may appreciate the warnings. I don't reccomend anyone doing this.
For me, though, heater works perfectly fine and has since I did this. Heater fires and comes on when called, and goes off when temp is reached. I run my heater everyday at 11am for 2 mins just to keep it honest and hasn't missed a day. Also, have prob gone in the spa at least 50 times running the temp up to 102-3.
For me, though, heater works perfectly fine and has since I did this. Heater fires and comes on when called, and goes off when temp is reached. I run my heater everyday at 11am for 2 mins just to keep it honest and hasn't missed a day. Also, have prob gone in the spa at least 50 times running the temp up to 102-3.
It’s similar to jumpering a gfci breaker because it keeps tripping.
It might work to keep the equipment working, but it is not the right thing to do.
- Oct 25, 2015
- 5,248
- Pool Size
- 25000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
K,
Thanks so much for the follow up. At least we do know the diagnosis of a bad board was correct and it makes sense the relay is more likely to fail than the other parts on the board. I'll add my concerns about the safety of this. One function of this board is to shut down the heater if anything is going wrong to prevent fire and even explosion. If you are going to run it like this please consider testing each of the safety devices in failure mode to be sure the heater shuts off. Another option would be to replace the relay with an identical part (less than $2 at Mouser) and then do the safety check. Of course as James indicates board replacement is the safest option and still saves you a LOT. This is definitely what I would do.
I hope this is helpful.
Chris
Thanks so much for the follow up. At least we do know the diagnosis of a bad board was correct and it makes sense the relay is more likely to fail than the other parts on the board. I'll add my concerns about the safety of this. One function of this board is to shut down the heater if anything is going wrong to prevent fire and even explosion. If you are going to run it like this please consider testing each of the safety devices in failure mode to be sure the heater shuts off. Another option would be to replace the relay with an identical part (less than $2 at Mouser) and then do the safety check. Of course as James indicates board replacement is the safest option and still saves you a LOT. This is definitely what I would do.
I hope this is helpful.
Chris
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That power relay is different in rev 14. Need to make out part numbers on originals photo before it had its top removed.
And the original relay may have been ok. Need to remove it from circuit to test. Or unscrew board and put a voltmeter on pins that connect to coil and see if its getting rated voltage.
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Just found out that you have to replace the old five button membrane pad with the new six button membrane pad when replacing with new control board.
Problem Solved for me. Same exact issue. AGS light on, all suggested testing and by passing and replacing sensors tried except for the flame sensor. Noticed the wire leading to it was chewed and broken but still attached. Cut it and reattached two sides of the wire. Heater back to working as normal. Actually it now stays on until it reached desired temp which was not doing before. If wire are ok, try replacing that sensor. My guess is that the jump you did on the board is bypassing the flame sensor somehow if that is the issue for you. Hope that helps.
- Oct 25, 2015
- 5,248
- Pool Size
- 25000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
Problem Solved for me. Same exact issue. AGS light on, all suggested testing and by passing and replacing sensors tried except for the flame sensor. Noticed the wire leading to it was chewed and broken but still attached. Cut it and reattached two sides of the wire. Heater back to working as normal. Actually it now stays on until it reached desired temp which was not doing before. If wire are ok, try replacing that sensor. My guess is that the jump you did on the board is bypassing the flame sensor somehow if that is the issue for you. Hope that
Bob, welcome to tfp. I think you have emphasized a great point to diagnose heaters. Often we see people checking voltage at the end of wires and when they get the wrong reading there is an assumption that a board or other component is bad. I like to check at both ends of the wire but checking for continuity is also a great idea when you don't get the result that is expected. Way too many people end up replacing components that are not really bad because of insufficient diagnosis and Analysis. Thanks for your comment. Chris
Bob, welcome to tfp. I think you have emphasized a great point to diagnose heaters. Often we see people checking voltage at the end of wires and when they get the wrong reading there is an assumption that a board or other component is bad. I like to check at both ends of the wire but checking for continuity is also a great idea when you don't get the result that is expected. Way too many people end up replacing components that are not really bad because of insufficient diagnosis and Analysis. Thanks for your comment. Chris
I believe if he had a blower failure, the gas valve and ignitor would still fire.
This can be verified by disconnecting the air pressure switch and start the heater.
Maybe if he had a filter pump failure, the heater would continue to fire.
This can be verified by disconnecting the wires connected to water pressure switch and see if heater fires.
Maybe if he had a thermal regulator fail closed, causing low flow and overheating heaters tubing heater would still fire.
this can be verified by disconnecting the wires connected to high limit thermostat. Same with ags .
First step to the heater firing-blower starting. The control system logic requires air flow to be sensed before anything else happens.
- Oct 25, 2015
- 5,248
- Pool Size
- 25000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
The control logic is a little "smarter" than you're giving it credit for:
- Blower failure would stop the ignition sequence. The control logic looks for actual air flow for a period of time (15 sec I believe) before igniter and gas valve get power.
- Disconnecting the air pressure switch stops the ignition cycle from progressing.
- Pump failure would trigger the low flow switch on the heater and keep the heater from firing.
- Disconnecting high limit also stops the heater from firing. You can bypass this sensor momentarily to trouble shoot but disconnecting it won't work.
But he forced the contacts closed on the power relay output that tells the fenwal that all sensors are good to fire up heater. So, no, there is no control logic anymore.
- Oct 25, 2015
- 5,248
- Pool Size
- 25000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
I believe there are more than this required. For the Fenwal:
- Power to the Air Switch contact after power is provided to the fan
- "Call for Heat" from the control board that in turn requires safe position for all sensors in the loop