Triton 400 Not Hot Enough

[pcmacd]

My Triton 400K BTU heater is not getting as hot as it used to.

I took measurements with a thermocouple years back when it was new, and either the "POOL" or "SPA" setting would get me 106F. No longer.

I've the schematic which I can read well enough. I am just trying to decide what "POT 1" or "POT 2" I need to change.

I suppose I could remove the potentiometer and measure it, take a SWAG and try a new one.

How-evah, I'd rather nail it the first time.

What the what? Even if I knew what kind of sensor it is (I would GUESS that it is a thermistor?) Sheesh. I seem to be answering my own questions. A thermistor resistance gets LESS as the temp GOES UP.

So, I'd guess I need to add a resistor in series with one of the pots, as the circuit will think the temp is lower when the resistance is higher? Looks like 40K or 50K ohms would do the trick?

 

[ps0303]

Thru the years all units start to lose their efficiency due to several factors. Your Triton is old and most likely at the end of its life. I wouldn't go adding anything into the circuit to trick it to heat more. You have then created a liability if it doesn't shut off. The unit could get too hot and maybe melt down. Why risk it. What does the inside of this unit look like? What does the heat exchanger look like?

 

[danpik]

^^^^^ +1
As Paul eluded to, you may need to have the unit serviced. The heat exchanger may be getting clogged up with carbon or other debris.