[Piedmont]

I have a solar hot water system AND a tankless oil boiler. The way they're configured I can use one or the other... what I want to do is on those extended cloudy days flick a single valve which will make the solar work as a preheater to the tankless boiler otherwise have it work alone. In my picture I show the 2 configurations I want the one valve to do.

I know this can be done with cheaper means and multiple valves but since my wife is involved I just want to be able to show her "flick this one valve and turn on the oil boiler" OR "flick this valve and shut off the boiler" (since my tankless boiler idles while on I don't want it on unless I need it). Would an apollo 3-way ball valve work to perform the two configurations I want in my picture?

Thanks!

 

[johnnydanger]

I can't say for sure if your way is incorrect. I'm not sure of how the tank less system is setup to run.

I will suggest 2 ball valves. or a 3 way ball valve where the outlet water is.

 

[Piedmont]

Thanks, you put a lot of work editing the picture! I finally found the instructions for the 3-way ball valve and it will do the trick (of either having my hot water come exclusively from the tank on those sunny days OR redirecting the warm water (after a few cloudy days) from the tank to the cold input to the tankless so it's a preheater configuration.

I just wish the handle could turn 180, only being a 90 means it can direct flow between one or the other outputs OR be a mixture of the two but has no position to stop flow.