1 1/4” pex

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HitzerHillbilly

Feeling the Heat
Oct 18, 2014
261
Northern Indiana
Was wondering what others thought here. So I installed some dual pex flex recently for my boiler, which is a just over 1” ID. My thought is to install 1 1/4” pex inside the house also because the inside diameter would be similar. And the fittings for that would actually decrease that a little more. Is it worth it to install the 1 1/4” inside the house or am i over thinking this? All my fittings i have now are 1”, but if its worth it i could spring for the 1 1/4”. I thinking flowing the extra BTU’s couldn’t hurt. Tell me your thoughts. Inside pex will be about 80 feet total. Total run from stove and back will be about 160 feet, including inside.
 
Depends on multiple factors-
is 160' one way or round trip?
What building are you heating (do you need the extra BTUs?)
What kind of heating system is it? Some kinds can tolerate cooler return water temps/low flow better than others. Coil in duct v. copper baseboard, etc. Baseboard heats unevenly at low flow rates.
 
Depends on multiple factors-
is 160' one way or round trip?
What building are you heating (do you need the extra BTUs?)
What kind of heating system is it? Some kinds can tolerate cooler return water temps/low flow better than others. Coil in duct v. copper baseboard, etc. Baseboard heats unevenly at low flow rates.
I misspoke earlier. Round trip is 240’, 160 outside and about 80 inside. From the stove to the DHW and back. Heating a 2,500 sqft cape cod and I am going to install a water to air HX in my furnace. So it’ll heat my DHW and house then back to the stove. Insulation is ok, could be better but I’ve seen much worse. The heating system is actually Geothermal. Love the thing in the summer! Cools like nobody’s business.....but it struggles in the winter. Especially with consistent temps below 20*.


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1 1/4" would allow you to keep pump sizing smaller. With the availability of 1 1/4" crimp fittings on places like supplyhouse.com the cost has come way down.
You'll heat ok with 1" with a hot air coil, but need a bit bigger pump to keep flow rates up. Not something I'd worry about too much. But it seems a waste to reduce size once you're in the house.
My .02 anyway.
 
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The heating system is actually Geothermal. Love the thing in the summer! Cools like nobody’s business.....but it struggles in the winter. Especially with consistent temps below 20*.
I couldn't agree with you more. Due to the same reasons you stated we heat with a wood burning furnace when the temps are low. I'm not fond of large electric bills in the winter.
 
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I couldn't agree with you more. Due to the same reasons you stated we heat with a wood burning furnace when the temps are low. I'm not fond of large electric bills in the winter.

We were running a wood burning stove in the basement, an insert in one living room, and a Harman P68 in another living area.....decided that putting in the OWB would allow us more even heating throughout the house, and we have about 40 acres of woods.


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We were running a wood burning stove in the basement, an insert in one living room, and a Harman P68 in another living area.....decided that putting in the OWB would allow us more even heating throughout the house, and we have about 40 acres of woods.
We heated with wood stove for a few years so I understand what you are talking about. That is why we went with a wood furnace on the second go around. An OWB or a gassifier with storage is even more superior since you don't have to baby sit it as much.

If money wasn't an object I'd have a gassifier with 1k of storage in an outside building. Keep all of the mess outside that way too.
 
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I couldn't agree with you more. Due to the same reasons you stated we heat with a wood burning furnace when the temps are low. I'm not fond of large electric bills in the winter.

I have a buddy who put Geo in a few years ago. I could never get him to tell me what his power bills were after that, just that they were more than they were expecting. I saw him last week & he finally told me. They were in the area of $900/mo the first winter. It was likely undersized for what he was trying to do with it - maybe? He had underfloor, on the two living levels, and in-floor in the basement. He said the upper levels were needing 140 water, which was the killer. I don't know a lot about Geo units really, but his does hydronic & hot (warm) air both. He has since run some ductwork to make more use of that, and has the under floor now tied into his fathers OWB (next door). Still over $300/mo. It has backup heat strips but he's never run them.
 
We heated with wood stove for a few years so I understand what you are talking about. That is why we went with a wood furnace on the second go around. An OWB or a gassifier with storage is even more superior since you don't have to baby sit it as much.

If money wasn't an object I'd have a gassifier with 1k or storage in an outside building. Keep all of the mess outside that way too.

Yeah, I have been so tired of tracing wood through the house to run our insert. Im sure I’ll burn more wood, but look forward to the more even heat utilizing the duct work, and loading only twice a day hopefully. It is not a gassifier, but I didn’t want to drop $10-$12k for the project either


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They were in the area of $900/mo the first winter. It was likely undersized for what he was trying to do with it - maybe?
I just checked 4 years worth of power bills. Our highest power bill during the winter was $221 US. During the winter our electric bill is generally between $175 - $200. I only run the wood furnace when it gets below 32F outside. Our house gets too hot if I run the wood furnace above those temps. We have a 4 ton unit with 2,400ft of pipe in the ground. Our unit runs 90% of the time in the first stage.

During the summer our electric bills are around $125. :) Before the geo we were around $200 during the summer. So essentially our bill has flip flopped.
 
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I just checked 4 years worth of power bills. Our highest power bill during the winter was $221 US. During the winter our electric bill is generally between $175 - $200. I only run the wood furnace when it gets below 32F outside. Our house gets too hot if I run the wood furnace above those temps. We have a 4 ton unit with 2,400ft of pipe in the ground. Our unit runs 90% of the time in the first stage.

During the summer our electric bills are around $125. :) Before the geo we were around $200 during the summer. So essentially our bill has flip flopped.

That’s good to hear, ours is not that way. Summer is generally a little cheaper. But cold temps in the winter can bring $400 bills. That kinda of money and the house still feels kind of cold. Just a little frustrating. I thinks the heat from geo actually “feels” different than wood heat. The geo was installed before we bought the place. It’s an open loop system also so my well pump runs quite a bit. Hoping to minimize that in the winter too!


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My electric bill runs about $125 in the winter, with my house and a small rental on the same meter.
I set the thermostat anywhere I feel like it too. :) Love my little GS100.