Hello all. I recently purchased an older house and this forum has been a great resource.

I think my baseboards are plumbed incorrectly. The previous owner had a new oil-fired boiler and hot water tank system installed prior to putting the house on the market. As I follow the piping out of the top of boiler, the first baseboard pipe it encounters is a diverter tee. From what I've read, it common practice to supply a baseboard with a plain tee and return the flow to the main with a diverter tee. Further, the baseboards' control valves are on the supply end of the convectors and the vents are on the return ends. Isn't that reversed?

Here is close-up of the diverters in my system:

It would seem to me that the water should be flowing from left to right. Based on how the boiler is installed, the water flows from right to left.

Am I backward? Does it matter? I don't want to freeze this winter...


Any help is appreciated.


-Dave

 

Dave, they'll work backwards. I'd relax and enjoy the summer.

I'd see how it works this winter before doing anything.

A good read on div-tee systems:

heatinghelp_dot_com/heating_howcome3.cfm

 

In addition to what Who wrote it is completely acceptable to have the zone valve on the supply to the heater and the vents ALWAYS belong on the heater water outlet where the piping turns downward.

If you have any heaters below the main then you need a Monoflo tee on both the supply and return. They will be installed in accordance with the arrow on the fitting.

 

or a picture, I like pictures...:



By the way, there might be a new boiler, but that tee has probably been there for 40-50 years...

 

Thanks folks. I'm less panicked now, but still curious.

I did read the "How Come" article(s), which is the only reason I can spell diverter-tee! But the author does mention that a tee placed "against" the flow adds turbulence which the circulator must overcome.

So I'm not too sure yet; is my flow direction working against all the tees in my system? (There are eight, none of which are below the main.) Since every convector's vent/bleeder valve is now on the exit/return side, did the boiler installer "set things right"? Maybe the flow has gone in this direction for its entire history and I've jumped to conclusions after reading the How Come piece.

Yes Trooper, those tees are original to the house which was built in 1960. Circa 48 years, well done!

 

Diverter tees _do_ add a bit of head (that's boiler speak for FRICTION) to a system. After all, they are restrictions in the pipe... installed in _either_ direction, they will add head, perhaps on the supply side a bit more... just the way they are designed. When a designer uses these, he has to take that into account when he selects his pump.

I think most installers would put the diverter on the return side, but that's not to say that it's necessarily 'wrong' to put it on the supply.

furd said:
And that's absolutely correct. Air in the system will tend to be removed most easily if the manual air bleeds are DOWNSTREAM, and located where the piping turns downward. Air is buoyant, it will happily flow UP into the heat emitter, and even horizontally across it, but it won't be happy about going back down again.

So, the bleeders are correctly placed.

Not to worry, you'll be fine.