Brand-new Pentair Mastertemp 400 won't ignite

T Man

Bronze Supporter
Feb 26, 2016
16
NE, Indiana
Installed brand new replacement Mastertemp 400 but it won't ignite

powered up, pad reads 62* water temp. heat is set to highest at 104* as well on easy touch and phone(automation). removed jumper & installed easy touch leads
as blower winds up, I get service heater light that goes out after what seems blower reaches proper rpm, then blinking heating light for a couple minutes. blower stops, service heater light comes on & stays on.
no codes on pad or board under top panel just the LED11 after blower stops
kill the power, do it all over again 5 or 6 times now. thinking air in gas line
gas is on, all valves on pipes as well as heater switch. I even bled the line up to the heater.
water pressure is good. 3hpVS @ 2200 rpm

is there something I've missed? Sorry for another Mastertemp thread but I could not find anything in the search... this heater is brand new, I do have the old heater available to swap parts if needed.

thank you, very frustrated !
 

JamesW

TFP Expert
Mar 2, 2011
19,734
Can you show a video of the startup and attempt to ignite?

Is the correct voltage selector plug installed?

The heater usually comes with the 240 volt selector plug installed.

What is the supply voltage?
 

JamesW

TFP Expert
Mar 2, 2011
19,734
Your old heater was also having problems as I recall.

You should check out the gas pressure at the gas valve inlet before the heater tries to fire and as it tries to fire.
 

T Man

Bronze Supporter
Feb 26, 2016
16
NE, Indiana
Perfect! I feel like a complete idiot! thank you James, it fired right up! I cannot believe I overlooked that
thank you very much! :smile:
 

T Man

Bronze Supporter
Feb 26, 2016
16
NE, Indiana
btw, the old heater issue last summer turned out to be the board. I'm installing the check valve that you suggested between the chlorinator and the heater.
thanks again, your help is truly appreciated!
 
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ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
18,959
Northern NJ
Can you elaborate on the check valve please. Thanks.
If you have a tablet chlorinator after the heater you must have a check valve in between the heater and the chlorinator to prevent acidic water from backflowing into the heater when the pump is off. You will likely find the requirement int he heater installation manual.