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[hrc200x]

I've been researching OWB for the past 8 months and hope to be installing one this summer. I'm wanting to do most if not all the the work my self, I've never soldered copper pipe and I think I want to use copper in my current furnace room to tie into the existing fuel oil boiler because it seems cleaner looking, and it will match the rest of the plumbing in that room. I will practice soldering on some scrap pipe first. The pipe from boiler to side arm heater and all crawl space plumbing will be PEX.

First question, I see some pipes that connect using solder are rough looking copper and some brass, are all these interchangeable or will different materials touching each other expand at different rates and cause leaking??

Unions on a side arm heater, good or bad idea? Use copper union or brass? Only have them on the domestic side so they can be easily detached when its time to change the water heater?

Hot supply pipe from OWB go to the top or bottom of the side arm heater for the water heater?

Since my system will be both copper and PEX is 1" a safe diameter to use for each? For instance 1" pex from boiler to side arm and back out, then where it comes into the furance room it will go to 1" copper. Or does one need to be 1 1/4" so they flow equally?

I'm going with a heatmor 200 not the gasser and from what I understand these run at a low pressure maybe 6 psi. My current fuel oil boiler has a auto fill water line from the well plumbed to it, can this be "T'ed" into and fill the OWB from inside the house, or will the 40 psi from the house cause a problem to the 6 psi system?

Currently my fuel oil boiler has just one circulating pump that kicks on when a zone calls for heat. I'm planning on adding another pump on a short loop that circulates the indoor boiler water over the water to water heat exchanger, this pump and the pump out at the OWB will run 24/7. 3 pumps total, 2 running around the clock. Is there going to be any issues when the short loop circ pump and the zone pump are both running? Am wanting to use the oil boiler drain valve and the pop off valve as the in and out for the short circ loop in 3/4" copper. Also pertaining to this is where to get power for the small loop pump. Attached is a picture of the current setup, Is there anyway to tell from the pic if I can rob power from the switch on the boiler to power the new pump.

There will probably be some pipe thread fittings, is the teflon thread tape ok to use or get the liquid version of the stuff?

Thanks in advance

[Steinacher Sales]

hrc,
I'm not to familiar with the side arm on the DHW. The Shaver Furnace uses a heat exchanger in the outdoor furnace.

The pex tube 1" is the same size as the copper 1", not need to change sizes.

Teflon tape is ok to use on thread fittings. Pipe thread compound with Teflon works well also!

Do not know much about the Heatmor, someone else will probably give some ideas on this.

Hope I helped some and good luck!

Greg Steinacher
618-401-0726

[idahohay]

The Heatmor is not really pressurized, there is a rubber ball on a rod that sits in the overflow exiting the roof. This offers a couple psi resistance to the expanding water and there is an exchange with the bladder that sits above the tank. This is a simple way to keep the system somewhat closed to the atmosphere but won't work with your existing autofill. Most fill their boilers through a valve teed into the return line to the OWB by hooking a hose to it from a convenient source, open both valves until water exits the overflow, then close both valves.

With the Heatmor, there is a valve to isolate the bladder until the boiler is full, then when no air is present it is opened so it can exchange water back and forth with the boiler as temperature varies.

[RSI]

Copper is larger inside than pex so 1" pex so no reason to use larger than 1" copper. It is not a big deal to change pipe size.
When soldering, clean the pipe and fittings really good. I would get the wire brushes for the sizes you are working with. Also use plenty of flux. It is easier to solder smaller size pipes than 1" so I would start with 1/2" and 3/4" and when you get a decent solder connection then do the 1".
The size of the pex you need will more depend on how many feet total you have than what size copper you use for a short distance.



Copper and brass can be soldered together with no problem. As long as the fittings are meant to be soldered you will be fine.

Unions on the sidearm are a good idea. You can get dielectric unions also that go from sweat to threaded and are a lot cheaper. They use a rubber gasket instead of the brass like a normal union.
If you haven't looking into using a 20 plate instead of a sidearm I would look at that too. Especially if you will be replacing the water heater soon.

The teflon paste is easier to get a good seal. If you don't use the correct amount of tape or don't wrap it right it will leak. The Blue Monster teflon tape is much better than the regular stuff.

[Steinacher Sales]

RSI,

The statement I made was to connect copper to pex with like a Shardbite fitting. Outside measurements for copper, pex, and cpvc are all the same.

Greg Steinacher
618-401-0726

[hrc200x]

idahohay, so the process of filling your boiler is, go out to boiler, turn bladder valve off, go back in house where the fill valve is, hook hose to it and to water supply, turn it on till water comes out the top of boiler, unhook fill hose, open bladder valve. My plan is similar except I would T into my auto fill line and put a shut off on the OWB side and hard plumb it to the return line. Then I would just need to open the valve to fill it. How often do you fill it?

Total feet of pex including both supply and return should be around 220 feet. 1" should be fine?

Would a dielectric union with the rubber hold up to the 180-190 degree water temp?

How does the 20 plate exchange work on a water heater, is it heating the water going to the faucet quickly as its leaving the water heater or does it keep the 40 gallons of water in the heater up to temp until it needs it?

[idahohay]

Hrc200,  I don't see anything wrong with tying into your auto fill, that might work pretty well. I check the water  in my boiler  all the time by feeling the bladder. I thought it was getting low toward the end of the season so I went through the fill process and it might have taken a gallon or two.

[slimjim]

  Hrc200x  I saw this thread earlier and did not have the time to respond, there are several things in your post that I would question, why would you after being concerned about pipe size, then use the 3/4 inch ports on the oil boiler ( pressure relief and drain ) to tag the oil boiler, not saying it won't work because it will but it will also reduce the flow, be sure to replace the relief valve and bring the exit from it to 1 foot from the floor, the auto fill on your oil unit should maintain 12-16 pounds of pressure in the system, it should not be used to maintain the OWB, I am hoping you are planning to use a plate exchanger to separate the 2 boilers, are you?

[hrc200x]

slim I think we are on the same page just some more explaining needed. The loop with the 3/4" line isn't in the same plumbing as the OWB loop with the 1" Pex and 1" copper combo. The 3/4" loop will have maybe 8-14 feet of pipe in it total, along with a small circulating pump, taco 007 maybe, or smaller if they make something? Are flanges available for pumps down to 3/4" line? Water to water heat exchanger is mentioned in original post 2nd to last paragraph.

The current oil boiler auto fill line has a backflow preventer and a reducing valve in it. Do you think I should borrow water before or after these two things? My original thoughts were before, now I'm thinking after, that way if the shut off to the OWB failed it would get the lowered pressure after the reducing valve rather than the 45 psi from the well pump, plus I would be making use of the backflow preventer

Some things I'm concerned about are what happens when the a zone calls for heat and that pump turns on. There will be two pumps running, both pumping water out of the boiler, but it should be coming in as fast as its going out. Another is powering the small loop pump with what power I have in the room. In the picture I posted am hoping to be able to borrow power from that switch that turns the boiler off, thoughts if its possible?

[slimjim]

Yes grabbing water for makeup from the outgoing side of the oil boiler makeup is ok, yes you can rob power from the oil boiler circuit, the easiest place to do this is at the thermal switch above  the boiler, you have some things there that could be improved while you have the oil boiler drained if you have the time and $

[hrc200x]

What improvements would you suggest?

Would you plumb the small loop so the hot water from the plate exchanger is going into the existing boiler at the drain or the pop off valve?

Where should the pump be mounted, can the 3/4" line support a pump hanging from it? Is there pumps smaller than the taco 007?

Thanks for the help.

[slimjim]

  Do you have multiple zone valves on that one circulator, if so the first thing I would do while the boiler is drained is to put isolation flanges on that old circ and put a spare on the shelf. 3/4 inch is not a lot of diameter to heat your home with, I have seen what you are looking to do work but I would feel much better with larger ports like putting bull nose tees on the supply and return headers and using them for the injection.

[hrc200x]

I'm lost now, if you have time please advise as to what isolation flanges and bull nose tees are, in the meantime I will do some research. Are you suggesting that I do away with the 3/4" small loop, or are you referring to the 3/4" that my current baseboards are?

Yep, one circ pump and 3 zones, maybe what the home lacks in pipe diameter it makes up for in base board? For instance the little office measures 6'x9' and its got about 15' of base board in it, basically the whole house is like that, rather than insulate better more base board was added, new insulation is on the 5 year plan, but I'd like a boiler first to start saving money quicker.

Also, with there being 3 zones almost the whole winter the house was only heating with one zone. The upstairs is one zone and I have that turned down to 50-55 degrees, bedroom/small office is another zone and that is a bit newer part of the house so wall insulation is so so, ceiling insulation is pretty good. The last zone is kitchen/living room and that is the older part of the home...100 years old, possibly no insulation or blown in cellulose. I've got the bedroom zone set at 65 or so and the living room one at 70, I think any heat loss from the living room was keeping the bedroom at 65 or above except on the real cold nights, and the upstairs part of the house is above the kitchen/living room so heat loss was keeping that close to 50 with the exception of cold nights. It should all be way better when i can insulate the living room and kitchen walls along with the upstairs.

[slimjim]

OK, can we expand a bit while I am on my way to VA. I will have Brian do some driving and perhaps we can talk, I will PM you my info

[randy_1]

Hey wait ... Brian can drive? I figured he either rode with you or traveled by dogsled team....