This is my second week using the Tarm 40. I have been working at learning how to use it and control it. Here is the skinny. One night was great. The temp outside was 29. I filled it up halfway at 10 pm. Turned up all thermostats to 70 and went to bed. Woke up and the house was still 70... and hot coals were all that was left. Last night was different. I did the same procedure.. put wood in at 10:00 pm. The thermostats were at 70. However.. it was alot colder last night... like 19? I woke up in the AM and the house was at 65. All zones were on and calling. Why would this be? The tarm was up to temp. Do I need more baseboard?
Rookie Too Hot too Cold
- Thread starter Birdman
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How is your system piped, series or primary/secondary? Where does your zone return water go?
The reason I ask is that in a series hookup the zones usually return to the fossil boiler and that mixes with the water coming from the Tarm reducing the available temp. It sounds like that might be your problem. If that is the case, more baseboards would help as well as turning the boiler up to say 190* if your system can operate at that temp. Let us know some more specifics and we'll figure this out.
The reason I ask is that in a series hookup the zones usually return to the fossil boiler and that mixes with the water coming from the Tarm reducing the available temp. It sounds like that might be your problem. If that is the case, more baseboards would help as well as turning the boiler up to say 190* if your system can operate at that temp. Let us know some more specifics and we'll figure this out.
The water returns to the oil boiler. Actually this AM I turned up the knob all the way up on the Tarm to get the water hotter.. because I thought this might get the water hotter through the baseboard? HOwever.. all it did was bring the temp in the Tarm way up.. almost hitting 100 C. I felt the circs and pipes to zones... they were warm not real hot...
WHy would the air lock not occur before? An idea I had is that when all the zones are open at teh same time.. then the lock occurs?... but the lock does not occur when less than 4 are on? Is this possible?
Might be a problem with your circ size....I have similar problems if I leave 5 zone open, pumps seem to not have enough "oomph" to move all that water. 4 zones, not a problem. My 5th zone is in the cellar, so I am not going to swap out my circs (since I really don't need to heat the cellar), but if you having all your zones on is a common need, you might need a bigger circ.
I have 4 zones. upstairs bedroom, downstairs bedrooms, water heater, and livingroom. The living rom zone has a big circ... forget the size but it is a big one. the other zones are Taco 007? i think.
The problem is that the hot water from the Tarm is trying to get into the oil boiler and so is the return water from the zones. You have 5 circs putting cold water in and only one putting hot in. This is a common problem with series hookups when there is a large heat demand. A larger circ on the Tarm would help, larger zones that don't run so long helps, but it is going to happen sometime in a series hookup.
That sounds like the right answer. It makes sense to me. I felt the suppy side behind the tarm and it was real hot..... real hot! then I felt the circs on the zones.... warm... not hot. I felt the zone pipes close to supply and return... warm.. not hot. It was like the real hot water was not getting into the zones. Your explanation makes the most sense to me. SOOOOO... my now my obvious question is..... What can i do about it? Is the only fix to put on a new circ( pump?) on the tarm to push this heat out when this issue happens? I am positive this will happen again... my house is a poorly built.... drafty log cabin. ( It hurts to say this because I know the guy who did alot of the building......ME!) however.... unlike alot of people.... the mortgage due each month is peanuts.... so it has its positives. Just need more heat to pump into it! And of course.. a new roof, better insulation in roof... etc etc. For now... I want to focus on getting more heat output. Tonight is going to be colder... I have a feeling the same issue will come. For now... can i keep one zone real low so the return rate of cooler water is lower?
I don't think storage will help in this - what you have is like one electrical outlet trying to run 75 items plugged into this outlet. You need to push more water to feed the 5 zones. Look at Taco's site and go over the pump graphs. I just got a 3 speed pump from Patriot-Supply and I'm really happy with it. It was cheaper than a locally purchased 007 and with the three speeds it pushes more or less than the 007.
Yes it probably would still happen.Birdman said:
No it would not happy in a P/S setup because the zones would get water directly from the Tarm and not from the oil boiler.Birdman said:
Mine works fine in series because the zones are sized to heat well with 140* water instead of having to have 180* water. When my 3 zones are all on and the Tarm is up to temp the available temp goes down to 140* until zones are satisfied. I have a Grundfos 15-58 3 speed pump on the Tarm running on high which has helped a lot as well. The zones are fed by 007s.
Tell me if am wrong. My options are:
1. Get a better pump to push more hot water for the Tarm supply side and hope this corrects the problem.
2. Somehow create less btu loss in the house so the Tarm does not have to have all zones turning on at the same time. ( This seems ridiculous to me... I bought it because it has a high btu output... yet I cannot use its high output with this option)
3. Switch it over to a Primary/Secondary system to take adavantage of the improved heating capability.
4. More baseboard?
Are there any other suggestions?
1. Get a better pump to push more hot water for the Tarm supply side and hope this corrects the problem.
2. Somehow create less btu loss in the house so the Tarm does not have to have all zones turning on at the same time. ( This seems ridiculous to me... I bought it because it has a high btu output... yet I cannot use its high output with this option)
3. Switch it over to a Primary/Secondary system to take adavantage of the improved heating capability.
4. More baseboard?
Are there any other suggestions?
What would swapping the return from the "big pump zone" to feed the return side of the wood boiler do?
Birdman said:
Do you plan on using the oil burner? I have mine "just in case", like if I go away for several days in the winter. SO I actually leave mine powered off, and ball-valved off, so even though I have two boilers, I am really running my tarm in the "only boiler" scenario.
Would putting in a couple of ball valves to "cut-off" the oil burner be an option? Good quality 1.25 valves will only set you back $50 for a pair...plus a bit of labor to put them in.
I would love to NOT use the oil boiler at all! We never go on vacation but i guess if we ever did.. i could just turn the house down low to like 50 aned let the oil boiler side come back on( open the valves back up). this sounds like an awesome idea. Tell me more about how this works? So I isolate the Tarm zone from the Boiler zone with 2 valves? And turn off the power to the oil boiler? What would happen if I just turned the oil boiler off(without the valves seapartating the boiler)? Can it do damage to my Tarm?
Basically, the hot output from the tarm needs to "T" into the output of the oil burner before it heads to your zones, and the return from your zones , just before it goes back into your oil boiler, needs another "T" where one leg returns to the tarm and the other to the oil boiler. Put the new ball valves such that flow will not go thru the oil boiler at all (you probably only need a single ball valve - because if the water can't flow out the top of the oil burner, it can't flow into the bottom either, but I set mine up so that I could actually remove my oil boiler, while my tarm is running, in case I ever needed to do maintenance or replace it).
Depending on how your existing piping is setup, it could be a very minor fix for you. I can't imagine any scenario (for me), where I would need the tarm to be running, and then have the oil kicking back on automatically when the tarm cools down - for me it would always be a conscious decision to cut-over to oil-heat. I can completely isolate, with valves, either my tarm or my oil boiler (and soon my storage).
Depending on how your existing piping is setup, it could be a very minor fix for you. I can't imagine any scenario (for me), where I would need the tarm to be running, and then have the oil kicking back on automatically when the tarm cools down - for me it would always be a conscious decision to cut-over to oil-heat. I can completely isolate, with valves, either my tarm or my oil boiler (and soon my storage).
Birdman
MrEd has good suggestions for a quick fix, but it may not be the permanent one you are looking for. The amount your zones run due to house heat loss is making the series hookup not work for you. What you probably need is to go to a true P/S setup for the long term and let your oil boiler sit cold until it is needed (ideally not at all). That way if you go away or the fire goes out it kicks on automatically and your Tarm and zones aren't running cold water through them until you get home to fix it.
A P/S hookup has the feed of both boilers going to zones through a T and the return from zones to both boilers through a T. There is a circ on both boiler return lines. When zones call for heat the Tarm circ comes on (if it is up to temp) and zones pumps come on. If the Tarm is not up to temp, the oil boiler circ would come on and the oil boiler would fire up to meet demand. Take a look at the sticky on it and do a search for threads on it. That is most likely your long term solution, but bypassing the oil would get you through the season for now. If you are planning on adding storage, factor that into your design before overhauling your system.
With that said, you may still be able to make the series hookup work with a larger pump on the Tarm, more baseboard, and you could even prioritize your zones so that if all are calling for heat only the most important ones run until satisfied and then the others come on after. This could be done using $8 relays and may help a lot. That depends of course on where you want heat in the house the most. I have no idea what your zones are. I can elaborate on the relays if you are interested.
MrEd has good suggestions for a quick fix, but it may not be the permanent one you are looking for. The amount your zones run due to house heat loss is making the series hookup not work for you. What you probably need is to go to a true P/S setup for the long term and let your oil boiler sit cold until it is needed (ideally not at all). That way if you go away or the fire goes out it kicks on automatically and your Tarm and zones aren't running cold water through them until you get home to fix it.
A P/S hookup has the feed of both boilers going to zones through a T and the return from zones to both boilers through a T. There is a circ on both boiler return lines. When zones call for heat the Tarm circ comes on (if it is up to temp) and zones pumps come on. If the Tarm is not up to temp, the oil boiler circ would come on and the oil boiler would fire up to meet demand. Take a look at the sticky on it and do a search for threads on it. That is most likely your long term solution, but bypassing the oil would get you through the season for now. If you are planning on adding storage, factor that into your design before overhauling your system.
With that said, you may still be able to make the series hookup work with a larger pump on the Tarm, more baseboard, and you could even prioritize your zones so that if all are calling for heat only the most important ones run until satisfied and then the others come on after. This could be done using $8 relays and may help a lot. That depends of course on where you want heat in the house the most. I have no idea what your zones are. I can elaborate on the relays if you are interested.
Let me know if I understand this then. In your design you have EITHER one or the other to use. In your setup you have to manually open valves to use the oil boiler OR to use the Tarm. In your design the oil can never " kick on " automatically to heat your house. Is that correct? If so... I guess i could do this as long as I don't have any lapses in my attending the Tarm... and I am able to judge the type of fire i need before leaving the house for the day. What if i judge wrong? If the oil boiler is valved off does this mean that teh electricity is still powered on for the oil boiler as mine has contols on it for the thermostats? This reply is to Mr. Ed's last post.
WoodnotOil. Thank you for the info. Why.... oh ... why did I not have the plumber set this up as a P/S?. I am really kicking myself now. I am not a plumber... but I wish I could have forseen this problem before the installation. I just got the bill yesterday... and now I am figuring out I need to change it to a P/S. Son-of-a. I read the sticky on P/S months ago... and I read it a few weeks before the installation as well. I guess it never hit me ( or any one else... even though i kept saying my house had a huge heat loss) that P/S would be better that series set up. I cannot afford to change anything now...however.. I think your suggestion of going to the P/S system is the right choice. If my system was just set up as a series..... can you give me some sorrt of idea of what it entails to change the sytem to the P/S? 2 circs and some valves and some copper? Anything else? Rough amount of time to do this for a plumber? 4 hours?
Woodnot Oil. I read your last post again.. and I would like you to expand on your idea of setting up realys to heat some places first and then others.
That depends on many things. If it could be done in PEX, it would be a lot cheaper and faster. However, most boilers are piped 1 1/4" copper for flow rate and to handle temps above 180*. If you could post a very accurate schematic of your existing system, I (and I'm sure others) could tell you ways to accomplish it. Doing it in copper, I would think more like 8 hours of labor (just a guess). Call up your heating guy and see if he has any ideas on the subject or would be willing to get it done right. He probably should have seen this coming as well. Sorry to be the bearer of bad news. I have contemplated switching to P/S but am making do with the series for now.
Birdman said:
Relays are like an "If Then" statement. You put the wire that feeds a less important pump through the relay and then have a more important pump charge the relay. When the relay is charged it is like an on/off switch. It would not allow the less important pump to run until the relay is no longer charged (by the more important one) then the less important pump could run. This relay would work for 110vac http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=Z787-ND.
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