Buderus panel cant get flow, can' get my dough

[Deleted User]

I recently removed a cast iron radiator connected to a two pipe reverse return system. I used the same 1" tappings in the old piping and reduced them to 1/2 copper and connected to the panel. The panel has been bled but water will not circulate when the zone and circulator are on. Any Ideas?????

Mike Murray

Too much restriction through the new loop?
Is the rad that you replaced typical of the rest of the system? Sounds as if you've thrown off the balance and the rest of the system is ignoring that branch. Perhaps a small circ pump through your bruderus?

[Deleted User]

The radiator which was removed is similar to the others in the circut. I simply removed the old i" iron and piped the panel with 1/2 copper. The new copper feed and return are less than 6 ft from the main. It does seem that the water is ignoring the branch

Steve Ebels

Are you sure

That the supply/return connections are correct? Left for supply and right is return.

Steamhead

Mike, I'll bet that was an old gravity system

with large pipes which kept resistance to a minimum. The low resistance in the existing system is why the water ignores the 1/2" piping to the panel.

You have three ways out of this: 1- increase the pipe size to the panel to 1" if possible, 2- run the pipes from the panel back to the boiler and install a dedicated circ to the panel, or 3- re-install the old radiator or find another radiator that will be a better fit for the room, and hook it up with 1" piping.

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"

[Deleted User]

I checked the supply and return piping and now you make me curious. The thermostatic radiator valve is on the left side of the panel. Are you saying the supply is the connection on the right?

Steamhead

It shouldn't matter

which side the supply is on, as long as it's big enough. But the air bleed should be on the return side.

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"

Mark Eatherton1

Go zinta the inside...

regardless of which direction the panel is mounted, the inlet is always the inside tapping and the return is always the outside tapping.

Sounds to me as if your piping system is "ignoring" the Buderi panel due to pressure drop. Mixing the supply and return will only cause the TRV to jack hammer when its trying to close. It shouldn't stop flow. Try closing the radiator valves on all the other radiators and see what happens.

Some times, on older systems, it is not a good idea to throw a high pressure drop device into the mix.

ME

bill clinton_3

zero flow?

Are you experiencing zero flow, or just very low flow?
Even the tiniest pressure differential will induce flow in just about any size pipe unless there is something stopping it: Like a low spot where cold water can settle in and because its heavier than hot water, refuse to move; or a high spot that has air that doesn't like to be pushed down and your delta p is not brawny enough to make it do so. Reversing supply and return causes very low flow eith a low delta p: If the supply goes in the top, you get thermosiphon action helping flow; warm water spreads across the top and, as it loses heat becomes denser and wants to settle toward the bottom.

Other than those, there is only one cause I can think of: something is physically blocking flow: perhaps some crud; perhaps a (perish the thought) closed valve.

Bill

Alan R. Mercurio

Mike, I'm not sure if these pictures will help? but I thought it was worth posting them. Good Luck.

Your friend in the industry,
Alan R. Mercurio

Oil Tech Talk

Robert O'Connor_3

Hey Mike,
I did same thing only hooked it up with 5/8" pex/al/pex, the resistance difference did the same thing to me. Have 1 72" and 1-48" on a 5/8" zone with dedicated pump they work great.

Robert O'Connor_3

Hey Mike,
I did same thing only hooked it up with 5/8" pex/al/pex, the resistance difference did the same thing to me. Have 1- 72" and 1-48" on a 5/8" zone with dedicated pump they work great. Small pump might be best way to get a happy paying customer.

Jason Roberts

What about monoflo tee?

I've had good results with diverter tee's, perhaps this would be a simple solution.

[Deleted User]

Wow! This is a great sight. I appreciate all this help. Thank you for the piping diagrams, The panel is piped backwards. I appreciate all your help. You can bet I'll use this site again.