Above Gorund Heater Used On Inground Heater

[charby97614]

I have a jandy 125,000 btu above ground heater but I want to use it on my 35,000 gallon inground pool..not sure if it would work though using above ground heater for inground. thanks for all help

[Bugman1400]

Not sure what you mean by an above ground heater unless you are referring to an above ground pool that the heater was once attached to. Is the 125K BTU heater electric or gas? The electric heaters don't seem to be as hot as the gas ones. That size heater seems small for a 35K GAL pool, however, it really depends on where you live. It also depends on how hot you like the water. If you are in Florida or Southern Cali, a 125K BTU heater may work. I live on the North/South Carolina border and I have a 26K GAL inground with a 400K BTU gas heater. I like the water on the hot side (88 deg by my thermometer...which is not accurate). In my area, without the heater, my pool water is around 68-72 degrees at the first part of the Summer. So, my heater needs to be able to produce a temp rise of about 30 degrees. Once I turn the heater on, it normally heats my 26K GAL pool about 2-3 degrees an hour. So, it takes the better part of a day to initially heat the pool. A 250K BTU heater would work but, take longer to heat to 88 degrees. Once the pool is heated, it takes much less BTUs to keep it at the desired temp.