I'm having trouble with my Mastertemp 400 also, same problem as this one. I don't get an error code, the heater just turns off after running for 3-4 minutes and the SFS led lights up. I've replaced the thermal regulator and stack flue sensor and I'm still having the problem. The heater was working fine a few weeks ago. The heater is 7 years old and gets used on weekends in the spring and late summer mostly. The control board was replaced about 4 years ago. I feel like every year I have to replace something on it. I'm about ready to stick a grenade in the thing and blow it up.
Mastertemp 400 - SFS error
- Thread starter jpcdmd
- Start date
Re: Pentair MasterTemp 400 problem
SFS is the stack flu sensor. So you replaced it and you still get that error LED? Did you look at all of your wiring to make sure nothing chewed any of the wiring?
"I'm about ready to stick a grenade in the thing and blow it up." Funny, I hear lots of customers say the same thing about the Mastertemp and the Sta rites, of which both units are the exact same just different enclosures..
If you want to see what the stack temp is, when the unit is running, hold down the pool or spa button and it will then show you the temp of the stack.
SFS is the stack flu sensor. So you replaced it and you still get that error LED? Did you look at all of your wiring to make sure nothing chewed any of the wiring?
"I'm about ready to stick a grenade in the thing and blow it up." Funny, I hear lots of customers say the same thing about the Mastertemp and the Sta rites, of which both units are the exact same just different enclosures..
If you want to see what the stack temp is, when the unit is running, hold down the pool or spa button and it will then show you the temp of the stack.
If you have replaced both the thermal regulator and SFS the problem is likely that the heat exchanger is sooted up. This isn't always the heaters fault.. Most of the time its caused by improper installation.. Low gas pressure is the #1 cause of heat exchangers sooting.
I had a tech look at it. He thinks its sooted up also. I found the coil assembly online for around $600. Looks like I'll just replace it.
So when the heater is on and burning and you hold down the pool or spa button, it reads 0? If so and you replaced the SFS with a brand new one, then you could have an issue with the control board.
After you fix it, head to the Grubens Uptown Tap and have a beer or a bloody mary. LOL
After you fix it, head to the Grubens Uptown Tap and have a beer or a bloody mary. LOL