Pool Heater size

[RSM18]

Hello all:

I had a 400,000 BTU Raypack 2100 heater which died last month after 12 years. I had a new heater installed and asked for another 400,000 BTU unit and thought that was what I was getting but the bill stated it is a 325,000 BTU unit. The tech said they always downsize new units because the new unit are more efficient and they draw more gas at start up and this can create an issue at startup with the unit cycling on and off. He said if I wanted the larger unit I might need to upgrade the line at the meter.

Doesn't make much sense to me that a new heater would draw more gas then an older one but I'm out of my realm with this.

Any information appreciated.

[PoolDoc]

He's correct that newer heaters are often significantly more efficient. That old Raypak may have been 60% efficient; I believe the current Hayward Universal heater runs about 83% efficient.

I'm not sure about the other. If he meant that over-sized heaters can cycle on and off too much, he's potentially correct. But if you understood him correctly, than some of what he's saying is just gobbledygook, probably due to ignorance rather than maliciousness. Over the years, while waiting at the pool wholesalers, I've heard pool guys express truly bizarre misunderstandings of how things work.