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[rmtrax]

Hello
   I need a expert plumber!!
 I still have a problem with pump application on my boiler, the pumps I have used won’t move water to home, and the boiler water is 180 F. Pump is running, removed pump and impeller is turning when powered up, no air in system when pump was installed!
Boiler system sits below my home 22 feet. The primary loop is 1 inch pex supply and return, totals 110 feet. The primary loop goes from boiler to the house and the system is open not pressurized. The pumps I used was a Grunsdfos UP 2696 F, GPM & Head specs looks good but didn't work. Some one said the reason was that that pump only works with a pressurized system and my system is open? Does anyone out there have their boiler below their house like mine? If so how did you overcome the problem? What pump did you use and have you ran into other problems?
                  Thank You , Bob

[RSI]

Is the pump at the boiler or in the house?

Are you sure there is so air at all in the pipes? 22' is a lot for that pump to have to lift but once the air is all gone it should be ok. Can you close both valves at the boiler and pressurize the loop with your domestic water and vent the air out at the highest point?

What exactly does the water on the primary loop flow through in the house?

[boilerman]

Don't expect the pump to push air out in an open system. Especially with a situation like yours.  Pump must be located at your OWF at the bottom of the hill. Make sure you have purged air out of supply/return lines by pushing both ways with domestic water pressure. Once you have done that, try partially closing the return valve at your OWF. Then plug pump back in.  It is possible the return water runs down the hill faster than your pump pushes it up the hill. This could ultimitely create oxygen in your lines and an air lock. This trick has worked for me on similiar installs.

[MattyNH]

Sounds like to me you need a bigger pump like a taco 011..I have a friend, his Central Boiler is below his house grad..Probably the same distance as you.. Pretty sure he has a 011 for a pump

[yoderheating]

I think the pump should be fine if all the air is out. If there is any air in the line it will not be able to move it.

[willieG]

i have made an error in calculating head inthe 110 foot line...forgive me ....your pump should be able to put out between 7 and 8 gpm in that length....i agree you have air in the lines.

[Scott7m]

That's why it's goof to install a flange kit that has a water hose option below the valve, then you simply hook up a water hose to it, close the ball valve above it, and let the water hose push out the system

[boilerman]

I agree. Every loop coming off a non pressurized open system OWF should have the valve that Scott just recommended to push air out with domestic water pressure. It would eliminate these air lock problems that continue to come up on the forums.

[Scott7m]

I agree. Every loop coming off a non pressurized open system OWF should have the valve that Scott just recommended to push air out with domestic water pressure. It would eliminate these air lock problems that continue to come up on the forums.

I don't always install them, probably should.  However I can usually tell by looking at the job whether I'm going to need them or not.  Then there are folks that simly refuse to pay the price difference