ThermGuard installed today!

[orangecrushcj7]

I would be more interested in only circulating the water, not running the actual burner. That way the moving water wouldn't be able to feeze. Plus it would be moving thru the heated space which would warm it slightly too. Anyone know how to do that? Would need to run the circulating pump without running the furnace.

Hi OrangeCrush,

You could use a ThermGuard to do that as well. You would just need to add a relay with 110VAC going to your pump in parallel with the control from the boiler. When ThermGuard switched on the relay, only the pump would run, not the boiler. It is a little more messy to connect than just attaching to your thermostat. If you had your boiler set to come on for 2 minutes every 2 hours your system would only be running 1.67% of the time. That is not very much energy to forget about your pipes freezing. If you are interested, I could draw up a schematic for you. I think all the parts including the ThermGuard would be under $80.

ThermGuard: $63.00
Relay : $7.00 http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=Z184-ND
24VAC transformer: $6.29 http://www.radioshack.com/product/index.jsp?productId=2102701&cp;=&kw=transformer&parentPage=search
Wire: ?? whatever you've got.

I am currently on a business trip and won't return until Tuesday 11/04/08. My road computer doesn't have the software to create a schematic and convet to .PDF but let me know if you are interested and I can take care of it when I get back.

Cheers,
John

John,
I would like to know more about how this set-up would work for me. It sounds to me like I may have 2 options I would consider. I would like to do one of the fllowing:

OPTION A. Like I explained in my original post, Leave the furnace off, and run the circulating pump every now and then to just move the water in the pipes to keep them from freezing.

or I don't know if this is possible

OPTION B. can the thermgaurd turn the furnace on to run, as you may have mentioned before, for 5 minutes, and circulate the water for those 5 mins, every 4 hours, and then turn the furnace off again? I don't want the furnace to run except for when the thermgaurd tells it to.

 

[imacman]

Orange,

don't know if John is watching all the threads, so i thought I'd chime in w/ what i know.

Both of your options A & B are essentially the same.....you want to just circulate water through the pipes occasionally. However, ThermGuard will not run your circulator pump (option A) by itself without some sort of other modification. It derives it's own power from the furnace electrical system, so that has to be turned on.

IMO, go w/ option B....just turn the thermostat(s) down as far as they will go. However,if it will only go to 50, and you feel that's too high, when you hook up the ThermGuard, leave one of the original leads off the thermostat connection, effectively rendering it totally disconnected...as if it wasn't even there, and the ThermGuard would then be your "thermostat" for that zone.

I personally wouldn't do that....what if the stove stopped working while you weren't home? There would be no way for the original system to turn on to keep everything from freezing.

Hope this helps

 

[bridgerman]

Orange,

Macman is beating me to the punch....Thanks Mac! Go with option B. It wiil work with everything as you have it now and needs no modification to your system. Simply hook up the ThermGuard to your thermostat, program it for 5 minutes every 4 hours and forget about it. Just that easy.

John

 

[orangecrushcj7]

Will it turn the furnace off completely with option b? Or will the furnace still run on it's own periodically to maintain it's internal temperature? The reason I don't want the furnace running unnecessarily is because it is over 40 years old and fairly inefficient. In the past the furnace would use almost 175 gallons of oil in the 4 month non heating season just to keep its internal temperature up. Even at today's relatively low $2.70/gal that is way too much money to burn when not needed. It is not used for DHW. And no, replacing the furnace is not an option right now. I only want it to be a back up in the event of a pellet stove problem

 

[bridgerman]

Hmmmm....interesting. If you shut off the oil supply to the boiler, ThermGuard should just circulate water through the pipes which should help keep them from freezing. Of course, as Macman says, if something goes wrong with your pellet stove, you won't have a heat source in your house. What you might want to do is turn off the 110 volts to your boiler until the thermostat calls for heat. It would be relatively easy to do. I guess the question is whether the pilot would stay lit if you turn off the 110 volts. If it has en electric ignition, I wouldn't see a problem. I don't know that much about older oil fired boilers. I guess I would try switching the 110 volts and see if when you turn it back on, the system will fire up. It should....I mean what happens when you have a power failure. Do you need to re-light the pilot?

If it fires up on its own, I'll draw you up a simple drawing that would use your existing thermostat to work an external relay which you could wire into the 110 going to the boiler. This would keep your boiler from using oil to maintain the temperature of the water when it is not being called for. The only down side is that it will take longer to heat the house when the thermostat actually calls for heat because the boiler would be cold.

Cheers,
John

 

[orangecrushcj7]

That sounds exactly like what I want to do. Yes, it has electric ignition, if i flip the power back on, it fires right up. I don't see a downside in the delay for the house to heat up in the event i need to use the furnace. If that is the sacrifice of saving a ton of oil, so be it. John, if you don't mind sketching that up, I'd very much appreciate it.

 

[Wet1]

The only other thing you might want to consider is that it's not healthy for it to continually cycle from cold to hot. In fact, I think all the manufactures frown on letting the temps fall to ambient. Someone please correct me if I'm wrong...

 

[bridgerman]

That sounds exactly like what I want to do. Yes, it has electric ignition, if i flip the power back on, it fires right up. I don't see a downside in the delay for the house to heat up in the event i need to use the furnace. If that is the sacrifice of saving a ton of oil, so be it. John, if you don't mind sketching that up, I'd very much appreciate it.

Orange,

Attached is a simple schematic for your application. I have also included the part numbers for the relay and the transformer. They cost $13.49 together. If you add a ThermGuard to keep the pipes from freezing, you would toss is another $62.99 for a total of $76.48. It doesn't take too much oil to recoup that investment. Please heed Wet1's advice and check with some qualified professional to see if you can take your boiler from cold to hot a few times a day without problems. If you can't, you can still use ThermGuard to keep your pipes from freezing without any modification to your system.

Cheers,
John

 

[orangecrushcj7]

Thanks John... I have a few questions that may be mundane for the rest, so I'll private message you....

 

[Bubbavh]

I have a 2 zone hot water baseboard heat with Taco circulators. Would I be able to hook up one unit (near the boiler) to run both zones at the same time?

 

[bridgerman]

I have a 2 zone hot water baseboard heat with Taco circulators. Would I be able to hook up one unit (near the boiler) to run both zones at the same time?

Hi Bubba,

That won't work since each zone needs to be independently controlled by the individual thermostats. Wiring them together so one ThermGuard could control both zones would create one zone. Now, that being said, many people with alternative heat sources try not to use their main home heating source during the winter. Some people shut them off entirely.

Soooo...if you want to combine both zones into a single zone, electronically speaking, you could use one thermguard and one thermostat to control the joined zones. That may not be too bad. You would still have one thermostat as a backup, in case the pellet/corn stove failed or ran out of fuel and the single ThermGuard would keep your pipes from freezing if your stove was running properly.

Now, from an electrical standpoint, the TACO controller (no relation to the tasty Mexican snack) provides 24VAC to each of the thermostats. I would want to be sure that the hot sides were connected in parallel and the neutral sides were connected in parallel. That way, you wouldn't be shorting out the 24VAC transformer in the controller. Since it is an isolation transformer, you could arbitrarily assign either lead as hot or neutral, but just be consistent for each thermostat. If it was wired properly, it should be as simple as connecting red to red and white to white.

I hope that answers your question!

Cheers,
John