New to OWB and Need Help

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Lelila

New Member
Jan 8, 2019
10
Upstate NY
Hi - I am new to OWBs and have a boat load of questions. We ran an indoor boiler for several years with great success. We recently moved to a 2400 sqft 200 year old brick house with no chimney access in the basement. So no indoor boiler. We installed a Heatmor 200x 80 ft from the house. We are heating with baseboard hot water (all new hot water pex) using the oil boiler tank as our storage. Oil boiler is our backup. The Heatmor is set to 185/170. We fired up this past Sunday at 6PM. Lowest outside temps haven't gotten below 20 degrees. Yet we can't get the house above 66. Even though the oil boiler fired often, we were at a comfortable 69 all the time on oil heat. What are we doing wrong with our OWB?

What questions should we be asking? Water temp, house size, depth of pipes, amount of pex, diameter of pex, etc?

Temps are supposed to be below zero this weekend. I'm afraid we'll be shutting down the Heatmor and firing the oil boiler. I have small kids and I don't want them getting sick because the OWB can't keep up and the house is too cold.
 
You had it installed? Or installed yourselves?

If you had it installed, get the installer back out. Troubleshooting over the internet can be a tedious process. There are lots of possible reasons why this could be happening. Could be as simple as an airlock, or as un-simple as a bad system design.

If you would like to try to get some help here, pictures of everything would be a starting point along with info on all pipe/water temperatures where the OWB water goes in & out of something.
 
Thanks for replying. We had it dealer installed with all his equipment and parts. We broke down, gave up our pride and called him this morning. He'll be here to help my husband tonight. Fingers crossed it's something as simple as air in the lines. This house is the original money pit.....
 
Hoping he used proper underground piping. And proper sized. Getting that part wrong would likely be the hardest & most expensive to fix.
 
Hoping he used proper underground piping. And proper sized. Getting that part wrong would likely be the hardest & most expensive to fix.
I believe he did. The underground piping came premanufactured. It was a large black insulated tube that encased both the feed and the return lines. He also had 2 inch rigid foam insulation placed over the tube as extra insurance. Buried 4ft. You aren't kidding - I don't want to try and dig all the frozen ground up.
 
I believe he did. The underground piping came premanufactured. It was a large black insulated tube that encased both the feed and the return lines. He also had 2 inch rigid foam insulation placed over the tube as extra insurance. Buried 4ft. You aren't kidding - I don't want to try and dig all the frozen ground up.
Any pictures of the pipe.
Premade underground piping isn't a good sign.
 
I believe he did. The underground piping came premanufactured. It was a large black insulated tube that encased both the feed and the return lines. He also had 2 inch rigid foam insulation placed over the tube as extra insurance. Buried 4ft. You aren't kidding - I don't want to try and dig all the frozen ground up.

Premanufactured could mean good stuff or, well, stuff that isn't so good. 'Proper' stuff wouldn't need any extra rigid over it - that part raises a bit of an alarm & suspicion

But you could be OK - I won't raise any more alarms without more info. Also, if this is a brand new install, even the improper stuff usually takes a little while before it goes bad. Unless it is in wet ground. Or water intruded right away.
 
Its a new install into an existing baseboard water system heated by an oil fired boiler. We ripped out the copper and replaced with pex because the half inch copper was old, corroded, leaking and original to the old drafting system.

He recommended the rigid foam because we also laid in a water line in the trench for a frost free hydrant for our lifestock.
 

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OK, from the pic I think it should be decent stuff. The suspect stuff has each pipe wrapped in bubble wrap looking stuff. It can get wet & cause you to lose a lot of heat into the ground.
 
UPDATE after last nights work. All pipes have had air drained. We found two rogue pipes going up to the second floor with no water in them at all. We cut them out and replaced them with pex and drained the air (what a funny thing to say, "drain air") and got the whole thing back on line. By 9 PM the house was back up to 66 and by 11 PM up to 68. This morning the house was steady at 68 degrees and nearly all the wood in the boiler was still unburnt and the temp was at 170. I asked my husband if we could bump the thermostats up to 70 and he said "don't push it now". Current temp outside is 30 degrees.

Temps are supposed to be below zero this weekend. Fingers crossed the system can handle it. I'll make sure I have my camp socks and wool sweaters ready just in case. Thanks again for all your input. Much Appreciated.
 
You didn't drain the air you purged the air. ;lol

Glad to see you got it figured out.
 
I would definitely try to bump the thermostat up to at least 70 to see if it can keep up. It'll be better now in these next few warmer days to figure out if you need any more tweaks to make things better.
 
Yes, now is the time to bump the stats. Don't wait until it gets colder out - it is easier to maintain inside temperatures, than raise them.

Glad to hear some success! While you're still ironing out kinks, you should be watching more than just the OWB temperatures. You should also at least watch temps in the indoor boiler - that is where the heat for your house is immediately coming from. As long as your OWB keeps your IWB hot, all else should fall into place. As long as you don't have another air episode - which could happen, sneakily, without you really noticing for a while. So you could also find accessible bare pipe spots, on the ends of your heating/rad zones, and feel them once in a while when they are supposed to be heating. If you happen to notice one isn't as hot as it usually is while it is heating, it could be another air pocket developing & restricting flow.
 
Congrats and stay warm! Hoping things remain in the good category, you are welcome to return here if the need arises.
 
Thanks everyone for the feedback. How can I tell if my indoor boiler temp is accurate? The indoor boiler gauge reads 130. However when the installer put in the system, which was shut off for 6 hours during the install, he noted with us that the gauge read 130 and never went down as the system cooled. After we fired on Sunday, the gauge didn't go up. Broken or am I really losing 50 degrees +/- over 80 ft?

Also, the Heatmor 200x has a fan that kicks on at 170 and off at 185. Should we change the low end to 175? Or is the 15 degree range normal? It takes ~8 min to raise the 15 degrees.

Lastly - is there a formula I can use to understand how many BTUs are needed to heat each sq ft of house 1 degree? And how can I apply that to how many gallons of water are flowing at what temp and at what rate? When I started this process I had lots of salesmen telling me I needed x btus for x sq ft but in the end I ignored them all and bought a unit that was 7 miles away from my house rather than getting one shipped from 850 miles away at a $4000.00 charge. My research said the unit was overkill but I didn't care. Now I'm afraid my research was wrong wrong wrong because my house is cold cold cold. 66 degrees again this morning and a balmy 30 degrees outside.
 
Sounds like the guage is wonky. He should have replaced it. Does it also measure pressure? Both are important for monitoring things. I have several guages around my system.

You should maybe get a decent IR temp gun. You could measure surface temps quite easily with one of those, in random spots. In this case, at boiler entrances/exits. They don't measure shiny surfaces (e.g. copper) good though, a spray of flat black paint fixes that. Very hard to determine where problems are without accurate temp data at various places.

Good underground piping should only lose a couple of degrees.

There are heat loss calculators online. Don't have links but Google should find one.

You still have issues - get him back out there. With a new install, it should be installed so it is working right. If the OWB is maintaining temp, there is an issue in the system somewhere that is preventing the heat being transferred to the IWB. If the IWB is maintaining temp, there is an issue with the IWB transferring heat to your rads. Although, since you said the IWB can heat the house when it is burning oil, that should rule that part out.
 
Ok your house is 66. What is the water temp of the owb? Are you out of wood?

From the picture you have good underground pipe so you can rule that out for heatloss.

Do you have any idea of what your house heat loss is? How many gallons of fuel did it take to heat in previous years?

If it only takes 8 minutes to heat 15 degrees in the owb it sounds like it is only heating itself and not the house. I would guess you still have a air lock issue somewhere
 
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This house is swiss cheese with a door. When we ran the oil boiler, even when it was below zero outside, we were able to maintain the temp in the house that we set the thermostats to. The boiler just ran more often. The owb still has wood in it in the morning and the water temp is ~175 so we haven't gone below the threshold of producing heat.

When it comes to an air lock - I'm sure there is some air in the system somewhere. I just can't prove it. My return is the same temperature as my supply. And my supply lines to both floors are so hot I will burn my hand if I hold on for more than a second. I do notice however I have a temp difference when I grab the lines in the front of the house going to radiator #3. So here yet another question:

How many feet of radiator should you have on one supply? Should the supply line going to each floor, if it's in the basement, be insulated? Our basement is a 38 inch stone wall. Cold, damp full of spiders and mice that didn't survive the peanut butter traps. Oh the carnage we haul away on a nightly basis. Buy stock in spray foam because we're keeping those companies in business. If we're not losing heat in the ground, are we losing heat in our 200 year old basement? And why didn't we a month ago when it was -6 and we were burning oil?

We just can't find the answer. BTW we have an infrared heat therm- I'll dig it up and start grabbing temps. Thanks!
 
Since you have had these problems, have you tried just running on oil again and see if that still heats the house?

If there is a zone problem (airlock?) , that should show up when heating with oil also.

You say the supply pipes to the zones are hot - what about the pipes on the ends of those zones? If a zone is airlocked, you should have a hot pipe at the start of the zone & a cold one at the end. Since water isn't moving through.

If you can follow the heat everywhere the water is or should be flowing, you should be able to find where the problem is.

We don't really know anything specific about your system, or how the two boilers are tied together. So we are kind of in the dark. Hence the tediousness of trying to trouble shoot over the internet. I would still have the installer out again.

(What is your system pressure?)
 
If your supply and returns are the same or very close to the same temps I would definitely say an air lock issue.

Could we get some more pictures of any other plumbing? Like heat emitters, highest points that may turn down and trap air, boiler plumbing on both boilers.
 
More pictures are definitely needed. I wonder if the installer used a heat exchanger or just hacked into the oil boiler and made it all unpressurized (and problematic).
 
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The system is not pressurized and the gauge on the oil boiler is a gauge for a pressurized system. The water is not getting into the probe and we'll never get an accurate reading from it. Today the OWB water light indicated it was out of water. How can 300 gallons disappear in four days? I hit the switch to fill it and 10 seconds later water came shooting out the overfill. I'm thinking air lock again. Unfortunately I didn't check for the boiler until I got so cold I checked and found it was 63 in the house. Too busy working my day job, which believe it or not, is not working on our heating system. I'm too old for this. When I thaw out, I'll take pics of the system.
 
Most OWB’s are open systems and are connected to new or existing closed (pressurized) systems via a heat exchanger so that the two are isolated from each other. Sounds like they opened up the existing indoor system and plumbed the OWB right to it directly. If that’s the case, I’d give up now until it goes back to two separate systems.
My unpressurized lines come into the house to a 20 plate exchanger for domestic hot water and then to a 50 plate for my two in floor heat zones. Everything on the house side is pressurized and air free. A problem with one doesn’t affect the other. Pictures will tell the story but I’m afraid you’ve got a mess, especially if you’re losing water at the OWB. Does it also heat your domestic hot water?
 
The system is not pressurized and the gauge on the oil boiler is a gauge for a pressurized system. The water is not getting into the probe and we'll never get an accurate reading from it. Today the OWB water light indicated it was out of water. How can 300 gallons disappear in four days? I hit the switch to fill it and 10 seconds later water came shooting out the overfill. I'm thinking air lock again. Unfortunately I didn't check for the boiler until I got so cold I checked and found it was 63 in the house. Too busy working my day job, which believe it or not, is not working on our heating system. I'm too old for this. When I thaw out, I'll take pics of the system.

I don't think 300 gallons disappeared. If it overfilled in10 seconds, it wasn't down much. That could be caused by a boil over, or air working its way out.

This is all the more reason to get the guy back out there, now. You paid for an install - it needs to be done right & to an operational level. Now that the OWB has water in it, you need to keep it going so it won't freeze up & break something, including the boiler. Does he want to jeopardize that? Let alone you being cold.

Are you sure it is all hooked together as one system? And all unpressurized? Eureka noted the issues with that. I know some say you can do that, but IMO it is making for a very air lock prone system. Especially with a two story house. And opening the indoor system to all kinds of corrosion promoting oxygen rich water.

Also the water doesn't need to 'get to' the probe to read pressure. If that's what you mean. If there is air & pressure between the water & the 'probe' (gauge?), the gauge will read it. Although I am not sure exactly what you were meaning there.