New OWB Install Planning

The price of 1" brass fittings is redonkulous. I've got everything I need now to plumb the back of the boiler now. My wallet hurts.

Got the inside water lines re-connected and ready to plumb into the heat exchanger.

Keep plugging away a little at a time.

 

Yeah from what I've been told buying the boiler itself is only half the cost...

 

I can see that. I'll have a good chunk tied up in fittings, pipe, and wire. Not half, but not an insignificant cost.

 

Got a few more things done the past couple days:

DHW heat exchanger, bypass valves, 1" lines to heat exchanger, and new tempering valve all done.

Boiler return cut-in done and ready to plumb into heat exchanger once it gets here.

Pumps are pre-wired with pigtails.​

I was hoping to get the underground pipe trenched in this week, but the weather turns to crap tomorrow so I don't think that's going to happen. I don't think I have anything else I can do until I see exactly how that pipe will get through the wall or the boiler gets here.

 

I was looking at a few things last night and remembered that existing circulation pump on the existing boiler was having a lot of issues last year. It's noisy (most likely pump bearings, not the cartridge), thermal overloads quite a bit...and it probably on its last legs. That pump will run about 100x more with the OWB this year than I've ran it in the past 5-8 years.

The way its installed there are no shut-off valves (or room to add any) so I'll have to drain and refill the entire system when (not if) it fails. Since the system is already drained I might as well replace it now.

I'll have my BIL who rebuilds pumps for a living go through it and I'll have one on the shelf for backup.

 

Always does. I figured it would be during cold snap when I'm out of town, wife would panic, and I'd get stung with a high dollar repair bill for a simple job.

 

And on top of all that you'd probably hafta redo it because the repair dude dorked something up!

 

I don't know anything about OWB's...but...
The cast iron radiators and fintube should be on separate runs/pumps. They don't work well together.

 

I know nothing about owb but my friend has one and his biggest problem is he did not insulate the pipe efficiently that runs from the boiler to the house. Therefore, heat loss, frost melt and of course it's at the end of driveway. So not only is he running inefficient but his wife gets her FWD vehicle buried in mud several times a winter, when she pulls forward to far and sinks.
Put money into insulated lines..

Note wife is not worse driver just Front Wheel Drive. His f250 does not get stuck..

 

I bought some high quality underground pipe.

I only have about 8 feet of fin tube. The rest is radiators or radiant panels.

 

Valves are your friend. Valve on each side of each pump and accessory. Little more money, but when you have to change out a pump, it is so easy to shut off two valves and replace then turn them back on. The fit on my old CB and on the new one we bought a couple of years ago. It is WELL worth the trouble now to do it.

 

Oh, I put in a lot a valves. All the new stuff I'm putting is has a valve on each side to isolate it should I ever need to swap it out.

As for the existing boiler, I don't really have an option to add valves. I'd either have to move the boiler or move a wall. I'm hoping to come up with a different setup in a year or two, but for right now it's not a priority.

 

Not much done in the past couple days as I haven't been home much. About to leave on a work trip so not a lot is going to get done between now and Thursday. Boiler gets here Sunday. Goal is to be 100% finished before I go on vacation the week after labor day.

New baseboard circulation pump is installed. That would have been a miserable job in the middle of winter....glad I did it now.

I decided to add a OWB fill valve inside the house in case I ever need to top it off in the middle of winter (hopefully I won't). It's real easy to do now and beats dealing with a frozen garden hose. I t'd off my house main line and will tie it into the boiler return line.

I'm going to go ahead and add a second pump to the back of the boiler. The manual says unless you are using both sets of lines, you should install a recirc pump to keep the flow thru the boiler up to make sure you don't get hot/cold spots. I got a pump big enough to reach out to the shop when I add that line, but I'll run it on low for recirc until I'm ready.

Pex going in the ground along with power at the end of the week. Set the boiler Sunday, plumb it and fill it next week to check for leaks, sit back and wait for winter.

 

That is insanely ingenious!!!

 

Mine's set up that way as well, took 35 min to fill from empty. Great set up.

 

Did you run 1/2 or 3/4 for the fill line?

 

1" only because that's what was where I tee'd it in. Put in a brass ball valve & voila', no hose no muss no fuss. Open valve & fill unit. Valves on either side of pump, & a third to isolate the pump in the event of perceived failure for diagnostic purposes (to check pump flow without losing water.

 

I wouldn't hesitate to put them on the same circs. I would try to arrange so the cast iron is on the ends of the zones and the water went through the fintube first.