Heater question

[CSE1965]

Hey everyone.
This year I added a Pentair Mastertemp 125 to our 24 x 12 intex AGP.
Everything is fine so far but....does this heater shut off when the flow stops or do I have to manually stop and start this?
Last year I used a camper 18L on demand and it worked this way with a 18 minute on off cycle timer and a rainbird temperature controller outlet that controlled the timer to the pump feeding the heater.
So...I found very cheap new in box Pentair as said earlier but can't find any information about its cycle. I am guessing it doesn't shut off when flow stops?
Thanks for reading.

 

[PoolStored]

Pentair MasterTemp Heaters - Further Reading

www.troublefreepool.com

 

[CSE1965]

Thank you so much. I was browsing for info but it was on Google. I should have searched here first.

 

[ajw22]

The MasterTemp has a water pressure switch that needs to be engaged for it to run.

But a pressure switch may not work, or may need adjustment, when the water level is above the switch as in your AGP.

A flow switch can be installed in place of the pressure switch - Heater Flow Switch - Further Reading

 

[CSE1965]

So I have the 52" high intex and the pump and heater are on the ground level with the bottom of the pool. My piping from the pool is a few inches lower that the pump and heater. So, heater is maybe at 48" or less from the inlet hose and skimmer to the pump.
I do have a check valve after the heater.
Think I still need to adjust the switch or add in one of the others?

Also....I still didn't read or understand if I can leave the heater on when my pump is on the 4 on and 4 off auto cycle.

 

[ajw22]

Think I still need to adjust the switch or add in one of the others?

Also....I still didn't read or understand if I can leave the heater on when my pump is on the 4 on and 4 off auto cycle.

I don’t understand what you are asking.

What pump and filter do you have? The MasterTemp 125 requires a minimum flow of 20GPM and preferably more.

 

[CSE1965]

Yeah sorry.
I have the Intex ECO20110-2 sand filter with SWG.
I have my pump auto cycling 4 hours on and 4 hours off. Will the heater be ok with this cycle?
I did shut my pump off and the heater burner did shut off. When I started my pump, the heater kicked back on.
I just want to ensure this is working as I hoped and didn't have to manually start and see top the heater if the pump was or wasn't running.

 

[ajw22]

You are worrying about the wrong things.

I doubt your pump cannot push adequate flow through the heater.

The pressure switch if properly adjusted or flow switch will handle the pump cycling.

Although Pentair recommends a 5 minute cool down for the heater before the pump stops.

 

[CSE1965]

So I have a mismatch of equipment for my desired result?
The pump is a 2150 GPH which ends up at about 35 gpm. That is within range as per the heater minimum requirement.

 

[ajw22]

So I have a mismatch of equipment for my desired result?
The pump is a 2150 GPH which ends up at about 35 gpm. That is within range as per the heater minimum requirement.

That is an optimistic specification that assumes no head loss from the filter or heater.

 

[CSE1965]

Well, this is the best I have right now. Just trying to make it work. It did raise our water temp for 70 to 79 overnight (about 8 hours)
Worse case is I will at least get it figured out by the time the season is over.