2 water heater tanks parallel question

[jacdela123]

I have 2 water heater tanks (3 years old) set up in parallel. Water heater tank2 broke down a few days ago, the plumber fixed it by replacing thermopile and control valve. Everything seems fine.

i just noticed today when i opened the hot water faucet, water heater tank1 burner immediately started, but water heater tank2 is still in pilot light.
i waited for many minutes and opened another hot water faucet (kitchen) but water heater tank2 is still in pilot light.. it seems water heater tank2 is acting as a back up..

Water heater tank2 is ok coz when I increased the temperature for tank2, the burner worked. As i said it seems tank2 is acting as a back up..

This confuses me coz the way i'm looking at the diagram below they should act together at the same time.
I'm also looking at my water heater I don't see anything that would make me think tank2 is acting as a backup.

I wonder if this caused tank2 to break down faster coz it's almost always on pilot light.

Another theory I see is water pressure inlet going to tank1 is stonger so way more hot water is coming out of tank1 as opposed to tank2.

 

[Dj2]

Is the enclosed diagram an accurate representation of your set up?

If so you have the cold/hot entering and coming out the wrong nipples.

 

[Sponsor]

 

[jacdela123]

when i checked online the problem is, it is not balanced.
i did notice outlet piping length is shorter for tank1 than in tank2.
plumber didn't put the T outlet intersection in the middle.
what i did is tried to balance the system by partially closing inlet valve for tank1.
i opened hot water faucet, i checked if both tanks burner starts, there's about 2 minute gap.
i'm fine with it. i guess that's the closest thing i can get to getting it balanced.

do you see anything possible problem with partially closing inlet valve for tank1.

i do know re-piping this is the proper way but for now i don't see the need to do that.