Overwhelmed Tarm newbie

[sandiapaul]

Greetings,

Just found the forum a few weeks ago and I have been reading, reading, reading! I have a million questions. Help with any/all will be MUCH appreciated!
We bought a house 4 years ago and it has a 20+ year old Tarm 500 running on oil.
I have 2 zones of baseboard and DHW from the Tarm. 1st year we did not have enough hot water so with the advice
and help of a friend I added an electric water tank, which is not connected to power for additional storage. This only partially solved the lack of hot water problem, replacing the HX solved the problem.
Now for my questions:
For season shutdown should I turn off the baseboard circulation pumps?
We are planning to go to wood this year, the original owners used wood for about 10 years but it has not run on wood for 10-15 years. What do I need to know/do? My main question is those mysterious Aquastats, how do I adjust them?
Can I set the unit up to automatically fallback to oil if the fire goes out?
It seems like I should be planning to add a heat storage tank, the only place I could put this is in a crawl space(its actually about 5' tall with a dirt floor, but it is 30' away from the Tarm, is this too far? How much better is the efficiency with a storage tank? Is there a real world number I could expect, like if you were burning 10 cords of wood now you will burn 8?
I'd like to add solar hot water eventually, can this be plumbed into the system?
Sorry for so many questions, but oil prices have fried my brain!
Many thanks!

 

[Eric Johnson]

Hey, welcome to the Boiler Room, sandiapaul.

I'm sure your Tarm is not a gasifier, but you will still probably benefit from adding storage at some point. The official line on storage is something like "up to 40 percent more efficient." But that could be anywhere from 0 to 40, depending on a lot of different factors. 30 feet away is fine. And yes, you can incorporate solar hot water into a hydronic heating system.

My guess is that the aquastats are all set up to work with the boiler as a combination wood/oil unit. I bet that when you get everything up and running, they'll do what they're supposed to do when the time comes. An aquastat is basically just a switch. They either make an electrical connection or break an electrical connection when the temp rises to the setpoint. Typically, if you have two on your system, one is set up to start the pump when the temp reaches a certain point (say, 140 degrees), while the other one (on an oil or gas system) cuts power to the burner when the temp hits, say 200 degrees. It's a safety feature. I wouldn't fool around with them until you know what you're doing, and maybe not even then. As I said, I bet they're configured to work with your setup as it's set up.

How about a model number on that old Tarm? We have people around here who know Tarms inside and out, and they can give you some specific pointers on your particular boiler and setup. About all I know is that Tarm always made damn fine boilers, and their combination units are about as good as you're going to get with a combi. That said, 20+ year-old technology isn't as efficient nor as clean-burning as the newer stuff. However, a well-designed system (piping, aquastats, storage tank, heat exchangers, etc.) will work with either, so you can drop a gasifier in there after a few years with all the money you're going to save on your heating bills.

 

[sandiapaul]

Hi and thanks for the welcome!
My Tarm is a 502.
I misspoke when I said aquastat, I meant to say "Automix" units. I understand the basic theory of operation but they have always been problematic.

Anyone with thoughts on if I should have my circulation pumps for baseboard turned on or off for the summer?

Thanks!