Newbie Needs Assistance

[CombatVetFamilyMan]

Newbie needs assistance....
I had a Tarm Solo Plus 40 (no storage) installed in the basement of a new construction 2 floor colonial with a bonus room above the garage. approx 2400 sq/ft. House is heated with baseboard units, garage and basement are not heated. I've never had a wood boiler before (moved from the city into the woods of New Hampshire). I've been playing with load size with the various outdoor temps. After two nights of not sleeping because it was 80 F in the upstairs during the night, I shut down the unit and am running on LP, not what I want to do but the wife is pregnant, so.....you know...happy wife, happy life. The temp on the first floor was 62-64 F. The outdoor temp during the night was approx 20 F. I have the valve set to open when the tank reaches 140 F, I have the fan speed running at approx 70%. the valve I'll call the safety valve is set to open if the tank gets to 200 F. The 2nd floor is the dump zone but temp in the tank has not gone over 200 F. Grundfos circulator pumps are set on high for the two zones on the first floor and low for the upstairs zone. When I went to bed I added 2-3 more pieces of wood in the fire box that was only coals.
This was the first Tarm for the installer so I had another guy who has installed several come and look at the set up and he told me it was correct, both plumbing and wiring. I was thinking about closing off the 2nd floor zone at night.
Any suggestions? Go easy on me, I'm just a rookie! I also have no training in plumbing or HVAC.
I will post photo's of wiring later tonight or tomorrow. Thanks in advance!

 

[mikefrommaine]

So the problem is the house is overheating on the second floor? Because the overheat loop is running even though the boiler is under 200 degrees?

And by 'tank' do you mean the tarm?

 

[CombatVetFamilyMan]

So the problem is the house is overheating on the second floor? Because the overheat loop is running even though the boiler is under 200 degrees?

And by 'tank' do you mean the tarm?

Yes Mike, I mean the tarm when I say the tank.
I have no control over the temp on the 2nd floor.
-Dan

 

[mikefrommaine]

Could be a couple different things.

The flow check may not be keeping the upstairs from thermosiphoning when the wood boiler is running.

Could be the aquastat that is supposed to turn on the overheat (2nd floor) zone is set to low. The numbers on the dial aren't that accurate. So that aquastat may be turning on your second floor zone when the boiler is only at 185 or so.


The green box on your back wall is a taco sr zone control. It should have lights on the right side that show which zones are calling for heat. When the wood boiler is up to temp and the upstairs thermostat is turned down is the light for the second floor zone on?

 

[Quincy]

You might need a weighted check valve to keep the hot water from rising to the second floor . The circs have an internal check in them on the output side of the pump there could be an obstruction caught in the valve keeping it in the open position allowing heated water to migrate, just a guess .

 

[Clarkbug]

Dan,

Does the upstairs have any issues when you run on LP? Just thinking that would help eliminate the thought of the need for a weighted check, since if you needed the check, you would overheat regardless of the fuel source.

Is your Solo shutting down once it gets itself up to temp? Or does it continue to fire? I would think what MikefromMaine has mentioned may be worth looking into. See what your zone controller says vs. your overheat aquastat is reading. You said you have "the valve set to open at 140 degrees". What valve in particular do you mean?

 

[stee6043]

It's worth noting that just because the Grundfos says "check valve included" on the back doesn't mean it's actually in there. They come with a sticker to apply on the back if you remove the check valve. It's entirely possible that your plumber removed them and didn't apply the sticker.

Ghost flows should be any easy thing to trouble shoot based on the fact that each of your zones have a shut off. Run your fire the way you normally would on a night when the upstairs would overheat. Once you feel the upstairs starting to rise in temp go down and shut off the ball valve on that zone.

It should be pretty obvious if your pumps are off and you still have heat going up to the 2nd floor zone that you're getting flow where you don't want it. The 200F water in your boiler wants to go up pretty badly, especially if you have cold water upstairs. I'd personally think you'll need more than the integrated check valves to prevent this flow. Adding check valves would be pretty easy for your plumber. I wonder if he struggled with the fact that your second floor is the dump zone. This means that in a no-power situation you have to have flow to that zone. As such, he really should be adding a normally opened zone valve to that zone and not simply a weighted check valve (I think).

And last, with this type of boiler you shouldn't have to "play with the load". Once it's properly running you should get consistent heat on every floor with very little guess work. What you're experiencing is a plumbing issue and not a "fact of life" for heating with wood.

 

[flyingcow]

I am just throwing this out there to see if t sticks. Any chance you have the Termovar loading valve? I had a ghost flow problem with it that only went away once a zone valve was out on it. I'm sure that info is of no real help, take it with a few grains of salt....and lemon...plus tequila.

But if your heating system worked fine on the existing furnace, seems that you might have a control wiring( in the wood boiler) that is that keeping your upstairs zone open.

Also, my house is 15 yrs old. The automag zone valves need new magnets and sometimes when my wood boiler gets rolling good the automags are weak and get over run and "leak" by. If run on just the oil furnace this doesn't happen.

Call the guys at Bioheat Tarm in Lyme. Check with them(if you haven;t already). They may be of help on the install.

I agree with Stee, this has nothing to do with how you load your boiler.

 

[CombatVetFamilyMan]

Thanks everyone for responding, sorry I haven't replied in a few days but we just brought home kid #2 yesterday. Several days ago I adjusted the aquastat about +20 F more than what it was originally set at. I haven't had any overheating problems upstairs since. I had no idea how inaccurate they can be (I have Honeywell aquastats). My TACO was running correctly, only the zones calling for heat were lit up. I also have Honeywell thermostats and now I'm curious as to how accurate they are. I'm thinking about changing them out to digital ones. Any suggestions for thermostats? Thanks for everyones help, I really appreciate it.

 

[BoilerMan]

Do your thermostats have a mercury tip bulb in them? Personally, I think they are the best ones for no-nonsense stats. Congrats on the kid# 2! They sure do change things. Just because it's digital doesn't mean it's more accurate, just digital.

TS

 

[Clarkbug]

Thanks everyone for responding, sorry I haven't replied in a few days but we just brought home kid #2 yesterday. Several days ago I adjusted the aquastat about +20 F more than what it was originally set at. I haven't had any overheating problems upstairs since. I had no idea how inaccurate they can be (I have Honeywell aquastats). My TACO was running correctly, only the zones calling for heat were lit up. I also have Honeywell thermostats and now I'm curious as to how accurate they are. I'm thinking about changing them out to digital ones. Any suggestions for thermostats? Thanks for everyones help, I really appreciate it.

Glad you got it figured out! Aquastats can have a variable or fixed deadband that sometimes plays havok on getting them tuned in right. Just tweak it until you find the sweet spot.

I would only swap thermostats if you are looking to add programming (the benefits of which are debatable, depending on who you ask) or your others are broken. I changed mine out to get programmable ones, only because I was having issues in my first year and needed to extend how long my storage would last.

Congrats on #2!

 

[CombatVetFamilyMan]

I spoke too soon! Over heated two nights in a row upstairs. I think I figured out that the Grundfos pump is not closing and it's always open to the second floor. The Taco showed that the second floor was not calling for heat but it was still flowing. I shut off the valve above the pump and for the last 6 hours there is no over heating.....and there is no heat upstairs. No heat upstairs is better than overheating for the time being. How hard is it to replace/repair the circulator pump? Any suggestions? The house is still under warranty, is this something I should tell the builder about?
-Dan

 

[mikefrommaine]

The installer may have taken the internal flow check out of your pump. Or the internal flow check may be blocked open by some debris in the system. You might not notice the thermosiphoning when burning propane because the propane boiler cools off much quicker between calls for heat.

If your house has a warranty I'd call the builder and let them know. Its easy to pull the circulator and check but once you start messing with their work then they have an easy way to deny responsibility if so inclined.

 

[CombatVetFamilyMan]

I also forgot to mention that one of the circulator pumps is constantly running, even when no zone is calling for heat. If you look at the first picture I posted it's the circulator on the lower left. It's wired from the pump, to a box, then to the Taco.

 

[Clarkbug]

What does that pump connect to? And what is the box its wired to?

 

[CombatVetFamilyMan]

Hey, that circulator pump I was just talking about....I think it is installed backwards, it's pumping water to the right, I looked at the schematics and if I'm reading it correctly I think it's supposed to pumping to the left side. I took a quick picture of the schematic. I called the builder, waiting on a call back. Could this cause the overheating problem? I'm thinking so

 

[flyingcow]

I know it sounds like a sales pitch.....but the schematics of a Tarm don't lie. At times though, it seems like you're looking in a mirror, to figure the layout on paper vs what you're looking at.

 

[Clarkbug]

Do you know which diagram that is? It should say something at the top like "PT-1" or "Solo-2". That way we can post a link and see the whole thing. Is it the right diagram? I only ask because Tarm did a great job and put out a bunch of them. Yours should show the wood boiler and the backup boiler on the same sheet.

But if your pump is going the wrong way, that could certainly cause some of the issues....

 

[mikefrommaine]

I agree that could be your problem. That pump could be pushing through the flow check on your 2nd floor zone. Maybe only happening on that zone because its the last zone on the manifold?

 

[CombatVetFamilyMan]

Called the plumber and he didn't believe me when I told him. After an hour or so he called me back and told me he would not be able to make it out until Monday to reverse the pump. I ended up doing it myself and it was pretty easy. Now I have another concern.
The pump I fixed is now pumping towards the "Forward" line of the boiler. This doesn't make sense to me and now I'm thinking that the plumber has the whole damn thing backwards.

 

[mikefrommaine]

The pump should be either pumping towards the return or away from the supply of the wood boiler.

 

[mikefrommaine]

On further thought... Can you post the full diagram that the plumber used?

I'm thinking that it will show that the supply and return manifolds for the house supply should be connected. Which I'm not seeing in your pics. The pump you are concerned about is probably the 'near boiler' pump and is wires to run whenever the wood boiler is up to temp. When no zones are calling for heat there needs to be a primary loop for the near boiler pump to circulate water. Without the headers connected threre is no where for the water to circulate when no zones are calling for heat, so the water pushes through one of the zone pumps.

 

[CombatVetFamilyMan]

I don't have the schematics the plumber used at this time. From what he was saying it sounded like he had some plans drawn up by someone at FW Webb, not sure why... Plumber is FINALLY coming tomorrow morning. The supply and return manifolds are not connected. I'll let you know what happens. thanks for the help everyone.

 

[Clarkbug]

Hmmmm. In your post above you had a picture of a partial schematic. Is that not the one that was used on your install?

 

[dogwood]

Looks like the partial schematic posted is an older dated version of one fully pictured on page 8 of the following link to the Tarm Plumbing Schematics book: (broken link removed to http://www.tarmbiomass.com/images/stories/documents/woodboilerplumbingschematic1211.pdf)

The schematic you posted "DWG NO Solo 2, Two Boiler Direct Design No Thermal Storage" is dated 8/11/08. The newer one in the link above with the same name is dated 7/14/10. Maybe if you compared the two diagrams you could come up with something. I don't know if the newer diagram had any revisions or not, that might be relevant to your problem.

Mike