Dual water heaters

I am designing a new home and want to have dual water heaters since we have four kids and two adults. I will be installing a hot water recirculation system and was wondering if I should plumb the heaters in series or parallel. The house will be on LP gas and probably 40-60 gal per heater. Also, any suggestions on designing my systems better are welcome. (Water well, septic, 4 bath...) Thanks!!!

Regardless of other's opinions, I do not feel that you can pipe a set of heaters in parallel, without using an engineered manifold, and get equal flow through them. I always do a series installation, and with a circulator pump I feel it is even more important to do so, since the pump will tend to keep both heaters at the temperature of the highest setting regardless of the setting of the other tank or if its thermostat has different parameters than than that one.

I agree with hcj about not trying to do parrallel. Depending on the layout of your house ( i.e. multi story, rambler, etc. ) you could consider a split system, that is two completely separated hot supplies.

I do not have any information on the efficency of this compared to a 2 tank series system. But it would allow you to have one system "hot" perhaps dishwashing, clothes washing,etc. and one system "warm" ...showers, lavs.
Perhaps others can comment on this.

So in series... Should I put the first one at a lower temperature (kind of a pre-heater) and run the pump thru the second heater only? Also, what would be the best insulation for the pipes to reduce heat loss?

dual heaters

There is almost no advantage to circulating through the single heater.