Ok Odt Plumbers, Im at it again...

[harrycalahan]

But this time its an easy Q. For residential setups, do you prefer tandem water heaters setup in paralell or series and why? Im split down the middle. I like that the paralell setup works both tanks 100% so proprosionally they should get the same wear and tear. It also costs me less in fewer valves to isolate the tanks in the event of a failure. In series costs me slightly less in piping but more in ball valves. Anyways, tell me what yall prefer and why. This will be two 50 gal gas units. Also, Im getting conflicting info online about sizing my expansion tank. One site said a 5 gal tank would fit me and another said much larger.

 

[PearlDiver]

But this time its an easy Q. For residential setups, do you prefer tandem water heaters setup in paralell or series and why? Im split down the middle. I like that the paralell setup works both tanks 100% so proprosionally they should get the same wear and tear. It also costs me less in fewer valves to isolate the tanks in the event of a failure. In series costs me slightly less in piping but more in ball valves. Anyways, tell me what yall prefer and why. This will be two 50 gal gas units. Also, Im getting conflicting info online about sizing my expansion tank. One site said a 5 gal tank would fit me and another said much larger.

My buddy who was the plumbing inspector back in my Savannah days set me up with two 40 gallon tanks. They were setup in parallel so both tanks run essentially, half duty. As for the expansion tank, we had one tank after the pressure regulator and before the water heaters. Both heaters had 12-14 inch risers. Hope this helps.

Sent from my XT1650 using Tapatalk

 

[erkinator]

But this time its an easy Q. For residential setups, do you prefer tandem water heaters setup in paralell or series and why? Im split down the middle. I like that the paralell setup works both tanks 100% so proprosionally they should get the same wear and tear. It also costs me less in fewer valves to isolate the tanks in the event of a failure. In series costs me slightly less in piping but more in ball valves. Anyways, tell me what yall prefer and why. This will be two 50 gal gas units. Also, Im getting conflicting info online about sizing my expansion tank. One site said a 5 gal tank would fit me and another said much larger.

Calling CAK

 

[CAK]

Parallel is the best way to hook up 2 water heaters because they each share 50% of the load and it's easier on the heaters as far as the work load is concerned. In series heaters there are again 2 heaters, one called the lead heater and the second one called the slave. The incoming or lead heater does 90% of the work wearing it out as much as half the life span of the slave not to mention that it can condensate all over the floor in certain run times and cause a mess. Most people believe it's leaking but more than likely it just ran a marathon. As far as an expansion tank there are 2 sizes in residential applications. Any installation over 50 gallon capacity you must use the larger one to handle the expansion while heating water. Make sure you install the expansion tank so that both heaters benefit from it and it can still work for one heater if one heater has to be shut down at any time. The next step is very very important, make sure all piping is the same length going to both heaters after the tee split or parallel hook up will not draw from both heaters correctly and that you use 4 valves so that you can shut one down if you need too.....

Any further questions hit me up I just retired from plumbing after 47 years. Hope this helps.....Carl

 

[Hayata]

Check out the offerings from what ever brand you are going to buy. Find the higher/professional/whatever they call it series and get a tank with an extra anode.

Water heaters will last a lot longer if you maintain them properly, draining, replacing anodes, etc. but most folks like me don't do the regular maintenance. Also, get a brass drain valve if you can.

Dang man - 100 gallon capacity - that's a LOT of water to keep hot. That will get expensive. Have you considered the tankless technology? Higher initial investment (venting is crazy expensive unless you can mount on an outside wall) but you're not paying to heat water 24/7.

Oh, and water heater insulation blankets can help a little according to my contact at Rheem from back in the day.

Good luck!

 

[woodstock]

Either way is fine if you use the right blinker fluid

 

[MegaFan]

Parallel for the win, as pro CAK stated. I have the same setup as he described at my lakehouse, where I shutdown and manually valve out one tank during the winter months when it is mainly just me and my wife in the house. In the summer months, when I know the kids will be there and all five bathrooms will be in full use, I valve in the second tank. They are identical gas water heaters and I rotate them for winter duty each season. When valving back in the second tank after its winter shutdown, I open the water supply line and the tank drain to drain some of the water into the adjacent floor drain to ensure good, clean water, then put it in back in service. I have also been pleasantly surprised to find that the second tank has never shown any signs of dirty water after sitting for about 6 months of non-use, which has been my experience with gas water heaters, unlike previous electric water heaters that always seemed to build up some amount of crud.

 

[jeep78]

You be running a bath house?

 

[erkinator]

all water heaters now are self cleaning, the days have gone where you should not need to flush as some advertizers claim. CAK has handled rheem heaters for all those years and we have had great resuls for lasting. Double Anodes take your warranty to 10 years.

 

[LT5150]

I agree with what has been said about parallel however I think series may be more efficient as far as energy usage. I piped mine in series manly because the house only had one heater when I bought it and I added the second and it was easier to pipe that way. I put the new heater in front of the 10 year old heater so the new one is doing most of the work.