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[dodges]

  Finally got boiler up and running about a month now and everything seems to be good.  Now id like to order a back up pump but not sure if I sized it right.  I thought I read where you figured 90º fittings with 1" line as 1ft of head but now saw on taco site its 2.62.  I also thought you figured in elevation but saw a post where " RSI " said he doesnt figure in elevation.  So im not sure ive got the right pump or not.  So heres a little background.  1920 sqft ranch very well insulated.  Boiler is 55ft from house and another 35ft inside, so 180ft round trip with a 10 to 12ft elevation up to boiler.  Theres 6 90º fittings and 2 ball valves heating with a 18x22 hx and a sidearm for dh.  This is a NC-175 and im using a grundfos 15-58.  If this is the wrong pump what would you recommend.  Everything seems to be working but its been unusually warm here in northeast Ohio.  Any help would be appreciated. 

[RSI]

If you are using pex crimp elbows, they are equivalent to about 10' of pipe length. If you are counting the threaded elbows on the boiler, those will not have much restriction due to the larger diameter.

A 15-58 pump should work fine. Just turn on the furnace blower so there is a load on the system and check return temp. If you can hang onto the pipe while the boiler is at 180 it is feels a lot cooler than the supply pipe, you either will need a larger pump or try to remove some restriction like elbows.

Did you remove the check valve from the pump? If not probably it is probably not worth pulling the pump off the stove just to remove it but you will gain a little flow.

[dodges]

  Thanks for the reply RSI.  The two at the hx and two at the sidearm are sharkbite slip ons.  The two just inside the house are pex crimps.  The return line feels exactly like the supply line.  Cant tell a difference.  Funny you should mention the check valve cause I just saw a post on that, so no I didnt.  I think ill just leave it in for the winter but ill definitely take it out for next season.  If I was to add radiant heat under the floor for next year would this pump still be ok.  Thanks again