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[WoodMOJoe]

What are the pros/cons of locating the pump at the OWB vs. inside the house?

My system will be OWB to DWH hx to hx coil in plenum of an upflow propane furnace in the basement.  Total difference in elevation of the system from one end to the other will be 3-4 feet, and a total run distance of about 60', one way.

I have read here on the forum that it is desirable to have the pump on the supply side of the system.

Unless there is a good reason not to, I think I want to put my pump somewhere in the basement, and inline before it gets to the hot water heater. 

The only downside I can think of of that arrangement is pump noise, and unless these pumps are VERY noisy that won't be an issue for me.

[yoderheating]

 Depends on how your furnace is designed. If you can I would highly recommend installing the pump on the supply side at the furnace. The biggest killer of pumps is an air bubble in the line and a pump installed on the supply side at the furnace should never get air to it. If you do install the pump in the house be sure and purge the air from the lines before starting the pump and never put the pump at the highest point in the system.

[WoodMOJoe]

Thanks for that Yoder, good info there.

I didn't mention in my original post, but the OWB will be the highest point in my system...sounds like I should go in the basement then?

The OWB will be a tank-in-tank homemade, I will be posting a thread on it in the Homemade section soon. 

Is there a way to insert .pdf files into a post on this forum?

[Scott7m]

Jo, a good way to make sure you got all the air out is to install isolator flanges on the pump that have an extra port where you can attach a garden hose to it.  I use a washer machine hose, female on both ends, makes hooking up the flange and the garden hose super easy, this allows you to force the air out with your domestic water pressure, works like a charm

Depending on the type of pump you choose, u may never hear it running

[WoodMOJoe]

Thanks Scott.  I definitely want to put enough ball valves/isolator flanges, etc. on the plumbing system to allow ease of service and maintenance/parts replacement.

Sounds like the arrangement you are talking about would also give me a point to attach a garden hose and run it out my garage door to drain my underground lines if I were to need to, I like that.

Glad to hear those pumps aren't too noisy, I'm still leaning on putting it in the basement from what you guys have told me so far.   

[XJCraver]

I put mine in the basement, and it's the very lowest point of my system.  Even if I'm in the basement, everything else in the house is off and no one else is home, I cannot hear it run.

The biggest benefit to me, is it's easy if it's inside.  It was easy to run my wires, easy to run the plumbing, and the pump is always easy to get to.  I'll never get cold changing / servicing it either.  I also added a boiler drain valve in my domestic cold water line, and another in my OWB pex line, that are close enough together I can hook a hose between them - easy filling of the entire system, right from the basement. I can drain the whole system from there too, right to the floor drain.

I'm not saying it's best to have it in the basement, but for me personally, I wouldn't have it any other way.

[yoderheating]

 I always put in a crossover line when I do the domestic hot water, turn the valve and push water back to the furnace and removing the air in the lines. Pump noise shouldn't be an issue, if its making enough noise to notice you will be replacing a pump very soon. Like I said before I always put pumps on the supply on the furnace however you will do fine with it in the basement if its lower than the stove. Just be sure to mount the pump the way the directions tell you to. Good luck and happy heating.

[WoodMOJoe]

Thanks XJCraver, those all sound like great benefits of putting it in the basement, I was sure hoping it was acceptable to go that way.  My office/mancave is right over where the pump will be, I kinda hope I will be able to hear a hum from the pump, just so I can keep tabs on it.   Ah, the sweet sound of $avings.   

Yoder, is there any place on the this forum, or on the web, that I might find some schematics for "typical" plumbing layouts for DWH and HX hookups.  My setup will be OWB to house, then hit the pump, then the DWH, HX coil in plenum, then back to OWB.  I have found some pics here on the forum but having trouble telling what is actually going on most of the time. 

I built (and plumbed) my house...but am not a "plumber", so whenever I encounter a new concept it takes me a while to get my head around it.

[yoderheating]

There may be but I don't know of any good ones. I would be happy to talk you through it. What type of dhw heater will you be using, flat plate or side arm?

[WoodMOJoe]

Was planning on using a 20 plate flat.

Here is a couple of pics that shows my layout.

The underground will come in through the basement wall about 8' to the left of the water heater, fairly close to where you can see my existing 1" PVC line coming in from the well.  Then I was thinking I would extend a board down from a floor joist to mount the pump on maybe?  And from there...

Also thinking I can get a 19x20 hx in the very top of my plenum (just below the floor joists) above my AC linesets, without having to unhook them.  My vertical plenum dimension is 20x20.

Appreciate the help!   

http://img.photobucket.com/albums/v646/barkeywayne/WaterHeaterandFurnace203-25-13_zps1790f0e4.jpg

http://img.photobucket.com/albums/v646/barkeywayne/WaterHeaterandFurnace03-25-13_zps3a9de780.jpg

[Firechaser]

I have a similar setup. From my boiler into the house, through the pump, through 30 plate exchanger,into furnace plenum and return to boiler. I mounted the pump inside. I ran power to a switch and then wired the pump off the switch. This way I can flip it on now and again in the off season. I looked at Central Boiler's web site for plumbing ideas. They have everything drawn out.

[WoodMOJoe]

Thanks Firechaser, I will check out CB's site and see what I can find...nice idea on the switch too.   

[yoderheating]

That looks like it should work really well for you. You have it correct, bring the stove line through the flat plate first and then to the coil in the duct. Be sure and have the water flow correct when you hook up the heat exchange. The domestic water and the furnace water need to flow in opposite directions and the hottest water needs to go in the top of the coil if you put it above the furnace. 

[WoodMOJoe]

...Be sure and have the water flow correct when you hook up the heat exchange. The domestic water and the furnace water need to flow in opposite directions and the hottest water needs to go in the top of the coil if you put it above the furnace.

I am pretty sure I understand what you are telling me here but would you mind explaining why you do it this way?

That is, why does the domestic and furnace water need to flow in opposite directions, and why does the hottest water need to go in the top of the coil?

I'm guessing the answer is that those arrangements are just basic, simple laws of thermodynamics but am really interested in knowing the "why".

Thanks!

Also, I have sketched out how I think this system will plumb, I will post it in this thread shortly.

[WoodMOJoe]

http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnaceSystemPlumbingSketch03-26-13_zpsc541b035.jpg

Here is my design sketch of a proposed plumbing schematic.  The color of a couple of the lines may be a little misleading, but I think I have the flow directions and connections correct.

Please give it a look and let me know what you think, thank you.