Brand new MasterTemp 125 not igniting

wireform

Silver Supporter
In The Industry
Aug 15, 2017
1,531
Spring Valley, NY
I got it out, tried to light it and the flame won’t stay lit when it gets close to the hole. The igniter was warm when I took it out and multicolored like it had been burning. I did not see any visible cracks.
It’s not that I necessarily have to have the pool heating up now, it’s just that Crud like this eats away at me and I can’t focus on anything else until I figure it out. I was up til 4 am reading and thinking about it. It’s driving me nuts!
Yes ,these things can and will drive anyone nuts. I'm not sure if I'm reading in to what you wrote, did you try lighting after it was disconnected that for sure can't work. Try lighting before it gets unplugged
 

Cpshockl

Bronze Supporter
Mar 28, 2020
22
New Orleans
Yes ,these things can and will drive anyone nuts. I'm not sure if I'm reading in to what you wrote, did you try lighting after it was disconnected that for sure can't work. Try lighting before it gets unplugged
Ok. No, I just tried with the igniter unplugged. And of course I just got it reinstalled. So try to light with the igniter out the hole but still plugged in is what your saying? Does it need a flame or will just the lighter spark work? The flame gets put out when I get the lighter working 3-4 inches of the igniter hole.
 

JamesW

TFP Expert
Mar 2, 2011
20,676
Don't try to light the heater like this.

The tub is under pressure. Don't try to start the heater with the igniter out.

Do you have a picture of the heater gas valve?

Check the gas pressure to verify that it's correct before the heater starts and as the heater tries to start.
 
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PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
4,862
Damascus, MD
How A Furnace Flame Sensor Works
A furnace flame sensor works by detecting the presence of a flame within the furnace. The sensor is a short length of thin metallic rod that creates a small current of electricity in order to confirm there is fire burning within the furnace. As the gas valve opens to begin the combustion process, the current is sent out from the sensor in order to detect the presence of heat from a flame.

Heating continues when the sensor detects the flame and all is well with the furnace. However, if the furnace flame sensor does not detect the presence of a flame within 10 seconds of the gas valve opening, it will shut the furnace down.
 

Cpshockl

Bronze Supporter
Mar 28, 2020
22
New Orleans
Don't try to light the heater like this.

The tub is under pressure. Don't try to start the heater with the igniter out.

Do you have a picture of the heater gas valve?

Check the gas pressure to verify that it's correct before the heater starts and as the heater tries to start.
F1397505-AE9C-4904-9B5E-D5F75838C6AE.jpeg
 

Cpshockl

Bronze Supporter
Mar 28, 2020
22
New Orleans
I don’t have a manometer right now. Going to try to get one to check the pressure. It’s just crazy to think that could be it when I had a heater hooked up that required more pressure a few months ago.
 

Cpshockl

Bronze Supporter
Mar 28, 2020
22
New Orleans
The switch on the gas valve is on, right?

You measured 240 volts line-to-line for incoming power?
Yes and yes. The manual shows what looks to be a metal switch, mine is just a little black plastic one, but it is for sure in the in position. 240 confirmed and 120 at the ground / hot wires.
 

JamesW

TFP Expert
Mar 2, 2011
20,676
I can't tell from the picture, but I will assume that it's on.

The next thing to check is the gas pressure.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
19,660
Northern NJ
How A Furnace Flame Sensor Works
A furnace flame sensor works by detecting the presence of a flame within the furnace. The sensor is a short length of thin metallic rod that creates a small current of electricity in order to confirm there is fire burning within the furnace. As the gas valve opens to begin the combustion process, the current is sent out from the sensor in order to detect the presence of heat from a flame.

Heating continues when the sensor detects the flame and all is well with the furnace. However, if the furnace flame sensor does not detect the presence of a flame within 10 seconds of the gas valve opening, it will shut the furnace down.
The MasterTemp uses flame rectification. Read...

 

setsailsoon

Gold Supporter
LifeTime Supporter
TFP Guide
Oct 25, 2015
3,379
Stuart/FL
Just as I was typing in front of the heater I’m getting the ignition lockout 3 blinks again. It goes on until the “service heater” comes on then it goes off
If the previous gas heater worked and you smell gas you probably have enough gas. It's not hard to check if you have a digital manometer. You can make one with clear tubing, water, and dye. They are amazingly accurate if you want to try this approach just search You Tube for it. Or you can disconnect the drip leg in the gas line to check there's no water. If not have somebody turn the gas line at the other end momentarily. You should hear a good hiss and smell gas immediately. Pressure will be very low and you can stop flow easily with your finger or hand. Pressure at most will only be 1 psi.

I looked at your manual and it appears your model does not have a fire box window. It's still easy to check. Just remove the wires and check the terminals on the igniter for an open circuit. If open, it's bad and needs to be replaced. See p 50 of the attached manual for the location of the igniter. You can also check for voltage during the ignition cycle. If it gets power then you know the none of the other sensors are an issue and it's more likely the igniter.

After you get the shutdown and check light look at the back of the panel to see if any of the lights are blinking if so take a photo and upload it here.

Based on everything so far I think the most likely problem is the power supply or igniter. Reason I suspect power more than igniter is the variability in the ignition module error codes. Either the power isn't correctly connected or the wire or connections are compromised. This is exactly what happened to mine. If you decide to check it just take a piece of cable directly from the breaker to the power connection for the heater.

All of the newer heaters use this flame sensing technology. It's safer since it actually detects a flame rather than a thermocouple that detects heat and infers a flame. Problem is it requires a perfect ground with absolutely no leakage.

I hope this is helpful.

Chris

PS File was too big to upload so here's p 50

1585514785737.png
 

setsailsoon

Gold Supporter
LifeTime Supporter
TFP Guide
Oct 25, 2015
3,379
Stuart/FL
If you still want to check gas pressure and don't want to wait for Amazon build one of these. I did it and it read exactly the same as my $30 digital manometer. Took about an hour to build after I scrounged up the tubing. Mine wasn't as pretty but it worked the same. My wife was not happy I used a ruler from her quilting table. So if you do this just mark the inches on the board after you fill with fluid.

Chris