Boiler water temp is 180, but water in baseboard only155?

[HavinFun]

Hello,
As title says, the water in my indoor boiler/baseboards is only reaching 155 degrees or so. I have a 100’ run from OWB to where the pex enters the basement. PEX is inside of a black corrugated plastic landscape pipe, and most likely neither insulated nor or water proof. An OWB supplier suggests that the pipe is water logged and robbing heat to the ground. I’m sure this is the case, that 20% of my heat is being wasted to the ground. How hot should the water in my indoor boiler be? When not calling for heat, there is a closed loop recirculating the water through 12 feet of pipe, the exchanger, and the boiler. I’d like to think it would get warmer than 155. I’m about to buy his insulated PEX pipe($1,200) in the hope to save the 20% of heat I’m losing. Does this square with what you folks know? Thanks.
John

 

[moor]

Hi John
Firstly what kind of radiators do you have in the house? My cast iron rads work best at around 160-180 depending on the outside temperature. My return temp is approximately 20 degrees cooler than my supply temp. Some fin tube radiators will work quite well at 155 depending on your radiator layout. Ideally you want to match your water temp output to your radiators so you're producing the right amount of btu's. Either way though you definitely want to get that extra 20% of heat into your house and out of the ground. Here's a link to fin tube showing the different btu's per foot based on temperature.
btu's per foot.

 

[sloeffle]

I'd take the advice of your OWB supplier and replace the underground lines. All you are doing is throwing heat into the ground and wasting your time, and effort on cutting up wood. With a good set of lines you'll loose 1 degree per 100' of line. What brand of lines are they trying to sell you ?

If you are pushing 6GPM through your current lines you are losing approximately 75,000 BTU's per hour if your circulation pump is running 24x7. You are burning an extra two cords of wood a month just to heat the ground. 25 degrees sounds like a huge delta T loss, 10 - 15 degrees is pretty normal with your line setup. I've burned a little over two cords in my gasification OWB the whole year.

 

[HavinFun]

Hi Moor and Sloeffle,
Thank you for the responses. The insulated PEX I’m looking at is Outdoor Boiler brand. He says that using the black landscaping plastic pipe, which is not waterproof, causes the heat loss. I figure 20% from both the in and out flow. Previous owner had the OWB temp set to 195-200 degrees. I replace aquastat after wrongly diagnosing a short, and new one only goes to 180 high side.
When house was run on oil when I first bought it, indoor boiler water temp was set to 195. The house (2200 sqft) heated up quickly, albeit to 60-64 to save oil. So I’m figuring out the house might not be well insulated, though new, and they needed the hotter water to keep comfortable.
OWB pump is Taco 011-F4, and indoor 010-F3, both run 24/7. Although this is my first year using the Heatmor CSS200, I am burning a lot of wood compared to what people say in their videos on utube. For instance, hold your breath, I burned through 300lb or so of not well seasoned oak going from 50 degree OWB to 155 degree in house in day and a half. I try to keep the house at 70 downstairs and 65 up, so there is a nearly constant call for heat. House is in SoNH, and though mild this year as winters go it is not warm out.
Thanks for getting this far. PEX pipe from Outdoor Boiler is about $1,200 for the 125’, and on sale, so I’d like to take advantage of price. Have people had good luck with it? Thanks again.
John

 

[salecker]

I have cast iron rads
My return temps from the house are usually 5 degrees colder than the temp going to the house st the average -20C outside temps. If the outside temp is -40C then the difference is around 8-9 degrees
i have foam in place lines 125' I ran parallel 1" lines but they tee back into a single 1" line which now that i know a little more doesn't make sense,but it was not my design.

 

[salecker]

Hi Moor and Sloeffle,
Thank you for the responses. The insulated PEX I’m looking at is Outdoor Boiler brand. He says that using the black landscaping plastic pipe, which is not waterproof, causes the heat loss. I figure 20% from both the in and out flow. Previous owner had the OWB temp set to 195-200 degrees. I replace aquastat after wrongly diagnosing a short, and new one only goes to 180 high side.
When house was run on oil when I first bought it, indoor boiler water temp was set to 195. The house (2200 sqft) heated up quickly, albeit to 60-64 to save oil. So I’m figuring out the house might not be well insulated, though new, and they needed the hotter water to keep comfortable.
OWB pump is Taco 011-F4, and indoor 010-F3, both run 24/7. Although this is my first year using the Heatmor CSS200, I am burning a lot of wood compared to what people say in their videos on utube. For instance, hold your breath, I burned through 300lb or so of not well seasoned oak going from 50 degree OWB to 155 degree in house in day and a half. I try to keep the house at 70 downstairs and 65 up, so there is a nearly constant call for heat. House is in SoNH, and though mild this year as winters go it is not warm out.
Thanks for getting this far. PEX pipe from Outdoor Boiler is about $1,200 for the 125’, and on sale, so I’d like to take advantage of price. Have people had good luck with it? Thanks again.
John

post a picture of the new lines if you can

 

[HavinFun]

I have 3/4” finned copper baseboard element. I think the insulation is not up to snuff, even though the house was built in ‘99. When it’s 90 outside, it’s 85 inside. There are a lot of windows facing SE, and no real shade trees, and no windbreak off of a large field to ENE.
Despite the temporary ailments with work to heat the house with wood, I enjoy it. I like being outdoors and using the tools to gather wood, and especially enjoy not paying $4,500 through winter months on oil to keep house at 60. Thanks for your responses.

 

[sloeffle]

Thanks for getting this far. PEX pipe from Outdoor Boiler is about $1,200 for the 125’, and on sale, so I’d like to take advantage of price. Have people had good luck with it? Thanks again.

I've never heard of this brand. The reputable brands are Thermopex ( Central Boiler ), Rehau, Rhinoflex ( Heatmaster ), and there are a few others out there. If the pipe he's selling you looks like -this- ( click me ) it's garbage. The good stuff is around $15 per foot.

Without any kind of physical device monitoring your water temperatures we are just spit balling on what your issue is. A 25 degree delta T from when the water leaves the boiler to when it comes back is not out of the norm. I've seen 40+ degree delta T on my system when I have the mixing valve for hot water turned all the way up and there's a call for heat. With that said, I'd still ditch the junky underground lines.

 

[sloeffle]

For instance, hold your breath, I burned through 300lb or so of not well seasoned oak going from 50 degree OWB to 155 degree in house in day and a half. I try to keep the house at 70 downstairs and 65 up, so there is a nearly constant call for heat. House is in SoNH, and though mild this year as winters go it is not warm out.

That's a ton of wood. You also have to remember since the wood isn't seasoned properly you are having to use BTU's to boiler the water. If a piece of wood weighs 10lbs and it has 30% moisture reading you are having to boil off almost a half a gallon of water. I'd recommend trying to get ahead with your wood so it's properly seasoned when you burn it.

 

[HavinFun]

Hi Sloeffle,
Yep, that’s the one, Heatmizer. Okay, so without going into why it is not the best (unless you might say why), I will look at the other brands. Thank you for the heads up. It doubles the cost, but better down the road.
Yes, I’m SOL this year for good wood. There was a whole lot left over when I bought the place -8 to 10 cords- but unbeknownst to me it was all pine. The oak I managed to find was 3-4 months dead in the ground, and happy to have had that. Going out this weekend to grab more downed pine and oak to try not to spend on wood.
Thanks.
John

 

[salecker]

There is a sticky on the top of the forum page on underground lines
The lines that i had foamed in place where the uninsulated Rehau O2 barrier lines
I asked for 6" around each line.The guy running the gun is the limiting factor when doing foam in place.
My house is pretty well insulated i have R120 in most of the roof with a couple gable roofs at R80
My windows are quad pane they are the same r value as a 2x4 insulated wall R12

 

[pettibone]

Did you measure the temp when the hot water comes into the house to see the difference between outside and inside or did I miss that?

 

[HavinFun]

Pettibone,
Yes and no on measuring the temps. I have a Fluke 88 multimeter with temp probe, but could not get an accurate or reliable reading. I didn’t want to spend for infrared temp gun, so have been going by what OWB temp says, and what water in oil boiler says after going through heat exchanger. I will try again, or see if I can borrow a temp gun. Thanks.

 

[HavinFun]

Salecker,
Thank you for mentioning the sticky on underground piping! The path is now clear on what I have to do. I will do the closed cell foam in system. I wasn’t keen on paying for the pre-made insulated pipe to begin with., and now I know there is a better option.
One other question; I have 1” PEX underground and to my heat exchanger, which uses 1” copper tube to make the connection. Can I upgrade to 1 1/4” piping even though it is 1” to the exchanger? Also, I assume there are 1” connections at the back of the boiler, and would they and exchanger piping be a restriction for the 11/4” underground piping? Thanks again.
John

 

[salecker]

When i did my lines i wanted to go with bigger than 1"
But the price and availability prevented that so the fix was to go with 4 1" lines 2 for hot and 2 for return.
I don't think that by the way it ended up getting plumbed that i am getting the benefit of 2 1" lines as both sets go back to 1" at each end. But the system works and keeps the house warm in extender -40 C weather so i haven't bothered changing them.
Another bonas is if a line was to fail i can trouble shoot and eliminate the leaking line and continue on.
-37 C last night and i woke up to a warm house after shutting down the boiler at midnight with storage at 175 F
Make sure you get the best foam installer you can, i went through a nightmare when i did mine. I had a great window in weather for a week and the guy who was reserved ghosted me. I had to phone everyone else and managed to get one company to come out as the good weather dissapeard he had equipment issues and had to return the next day.I had to hoard in the 125ft trench and backfill material to keep the snow and water out and then backfill with clay that i kept as dry as i could.My wife ended up with phenomena working in the wet conditions as we did the best we could with the conditions given us.

 

[HavinFun]

Salecker,
Thank you for the information. I just looked at my boiler, and I can go to 1 1/4” lines as the boiler has what appears to be 2” fittings into the water tank. So, with a 1 1/4” reducer I’m good. That means that I’ll have to replace all fittings, pump, and exchanger and plumbing to it. I will look at the cost and decide. I think with actual 170-180 degrees water in the pipes in the house I may be fine here in SoNH with well-insulated 1” underground pipe.
Winters around here any more have been too mild, kind of unsettling. No frozen ponds and rivers, or only for a short spell - not good for the environment.
Glad to hear you finally got it done. Been ghosted on some jobs and it’s a real pain.
Best regards.
John

 

[sloeffle]

You need 1 1/4" lines like I need another ex-wife. 1" lines should be more than adequate from what you doing. You generally only jump to lines greater than 1" in a residential setting if the boiler is far away from the building you are heating or you have a large heat draw.

20 degree delta T * 8GPM ( max GPM for 1" line ) * 500 = 80,000BTU - that easily heats my house ( almost double the amount of BTU required ) and should heat generally most others.

When I was talking to people about having my house addition spray foamed most folks told me it wasn't worth their time to come out. Luckily I found two brothers that were looking for work to come do it. The foam in trench method is a great method but I think you'll have a hard finding someone to do the work for you. I'd just contact your closest Heatmaster or CB dealer and see what they charge for lines. Cash talks too.

 

[HavinFun]

Sloeffle and Salecker,
Thanks. I’m only dealing with 100’ run to a 2200-3100 square foot place (when addition gets finished, no rush). That’s good news to keep 1” pipe. Will explore trench; if not realistic, will go pre-made. Best regards.

 

[hedge wood]

HavinFun When I installed my Garn in 2009 I went with closed cell foam in the trench as my lines are 450 feet from the Garn barn to the house. . I went with one inch Pex . I installed four lines two feed and two return. I have three furnaces with heat exchangers and another heat exchanger for my domestic. One inch has been plenty big on that long run. For you the good premade will probably be the best.

 

[HavinFun]

Hedge Wood,
Thank you for that. I have a backhoe and doing the trench won’t be too bad. I can probably lay the line myself, but will have a friend help. I have a friend who owns an OWB. She told me when they put her lines in they were just laid in the dirt and covered. Her run is about 25’, but it still makes you think about some workers.
I’m hoping to get ahead on the wood. I’ll be buying a 14’ dump trailer of hopefully fry logs and will cut and split this weekend. I have some downed oak that I hope to have out of the marsh soon and get that ready to use in a year’s time. There are also a couple of pines down, and that will be good to harvest too. I know the freshness of the wood is hurting the burn but it’s all I have. This is my first year doing this, but it is satisfying. Learned a lot of lessons. The money I saved on oil I’ve put into equipment, so now get to work outside a lot.
Thanks again.
John

 

[hobbyheater]

Hedge Wood,
. The money I saved on oil I’ve put into equipment, so now get to work outside a lot.

A good wood splitter makes wood gathering fun also !

Thanks again.
John