Water Heater Coil

Thanks for the advice guys. But after discussing this with Greg I've decided to just let the pump run all season. It doesn't use any electricity to speak of and from what I gather it will last forever.
TGMC as far as the toe kick heaters being run by a thermostat, that isn't a problem because I have installed isolation valves so I can either run them off my coal stove or switch them over with the valve to run off the oil burner. Just a couple of quick turns of a couple of ball valves and they're back onto the oil burner.
Tom

rouxzy wrote: But after discussing this with Greg I've decided to just let the pump run all season. It doesn't use any electricity to speak of and from what I gather it will last forever.
Tom

The starting and stopping is what kills them, it will last a lot longer running continuously.

With the colder temps the Harman Mag is producing a lot of hot water. Relief valves have not blown off yet that I know of. Gonna do what rouxzy did and hook up the one toe-kick heater that is in the kitchen to the coil. Already have the valves on the heater to isolate it just have to install valves on the coil/tempering tank. Seems like it will work great, and get some heat down low on my cold tile floors. Tom how are those heaters working out?
Stay warm, Jimmy

Jimmy,
They are working out better than I thought they would. They put out real good heat, and they also work as a thermostat for my water heater. The water in the heater will never get above 150 so long as I have these things hooked to it. I defineately highly recommend doing it. In fact I'm in the process of putting in some radiant heat in another room and possibly adding another coil in my stove to take care of that. The best part is my wife is 100% sold on coal heat. She even now goes down to the cellar and shakes it and feeds it every 6 hours while I'm at work.
Tom

Well,
After furthering my research on radiant heat I found that the water temps in the piping only need to be 130 - 160. This is pretty close to the range that I am now experiencing so I will be doing it. I have already bought the materials and will be doing it in the next couple of weeks.
Tom

Hooked up the kick-space heater to the coil. Need to get the lower aquastat, there is a 140 deg in there. Had to bypass it, they make a 120 deg aquastat, just trying to find who sells it around here. Right now I have it turn on when the circulator turns on. Was only warm at first, then I turned one of the valves almost closed so the water moves slower in the coil picking up more heat. Seem's to have done the trick. The water comes out of the bottom of the tank then to the circulator, coil, kick-space heater, then back into the top of the tank. The water from the bottom is not hot, especially if someone took a 1/2 hr shower, or did a load of laundry. Wondering if I would be better off reversing the circulator to draw off the top of the tank and putting the water from the coil into the bottom? Any ideas???
Stay warm Jimmy

jimmy
the way you have the pump is fine. It helpes with the heat stratification in the tank, and also helps keep the relief valve from blowing off all the time. If you want more heat at the toespace heater you might try putting the heater before the water tank. then run the pump on a rehostat to slow it down to get more heat. I've never been one for closing off valves, but if you must , close the one going into the pump. it has better results.
good luck

pittston val

Jimmy,
What you want to do is have a tee in the hot water line leaving the tank to the supply line of your heater. The return line will go to another tee to the cold water inlet to the tank. Keep all your valves fully open. With this setup the domestic hot water is priority and you will get no backflow into your cold water supply. The way you have it setup right now you are getting the coolest water out of the tank for your heat. You do not need an aquastat with my setup. The heater will act as a thermostat for the tank so you will not blow the pressure relief valve. I have the circulator pump running at all times. This will not harm the pump, in fact the constant starting and shutting off of the pump will do more damage to it. Plus these pumps use very little power, so you will not be using much electricity to speak of. With my setup with tow toe kick heaters I am heating a bathroom and a kitchen with it. The heaters do shut down when showers are being taken but after a few hours they are back on and pretty run quite a bit. This setup works very very well.
Tom

Tom, the way it is now it is not working out. Just warm air out of the heater. Thinking of turning the circulator around. This will draw the hot water off the top of the tank, then to the heater, then to the coil, then back to the bottom of the tank. Have to drain the tank down to reverse the circulator(Should have put valves on each side of the pump, will do that when I have the tank drained, for future replacment) Thanx
Stay warm, Jimmy

Hi Jimmy, the very hottest water should be the water coming out of the coil in the stove, it should be near boiling. sending it through the toe-space heaters should cool it to maybe 130* or so.

Then it can go into the domestic water tank.

You may not have lots of heat while the domestic tank is cool, just after a lot of hot water use, but given a little time it should get back to ~100* and then the water entering the coil will be warmer and pick up more heat and make the toe-space heater more effective.

How hard are you burning the heater right now?? On a cold night I think you will be getting a lot of heat from the water coil. Just not all the time, 'cause the coil is trying to heat 40 gallons of cool water too.

Greg L

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Greg, I have a snap disc thermostat attached to the pipe at the stove. This turns the circulator on at 120 deg and off at 110 deg. So the water heats up, circulator kicks on and is replaced with cold from the bottom of the tank. Circulator shuts off and the process is repeated. I'm thinking that maybe I should turn the feed down on the Harman Mag thus it will run hotter longer. Right now it runs most of the day in pilot mode. If it runs longer to satisfy the wall thermostat I would get more hot water. (I think ) I thought this would be a no-brainer but so far has not worked out the way I had hoped.
Stay warm, Jimmy

Hi Jimmy, I think the lack of heat for the coil is the issue. Tom has the stove cranking all the time creating a lot of heat in the coil.

Greg

Greg, I think your right, before I reverse the circulator, I lowered the feed rate to give the stove longer burns. It will take awhile to see if this has any impact. Otherwise I'll reverse the circulator and draw the hottest water from the top of the tempering tank. Just wondering if this will cool the tank too much???
Stay warm, Jimmy

Jimmy,
Like Greg said, I run my stove pretty good so I do create alot of hot water. You won't gain anything by switching the pump around. Again as Greg said the hottest water is coming right off the coil and I believe that is where you are picking it up from. I don't know what you are running for toe kick heaters but the fan on mine doesn't come on util the water temps hits 150 then the fan shuts off at about 125. My fans in both heaters run for most of the day if nobody is taking a shower.
Tom

Turned the feed rate down and is burning hotter longer. Stove temp is about 500*. After running all night I can keep my hand on the pipe coming out of the coil. Wondering if I'm losing a lot of the heat on the run to the tank and kick-heater. It's about 25 ft one way, all the pipes are insulated thou. Going to pick up a 120* surface mount aquastat to put back where I removed the 140* on the heater (that one never kicked on) Right now I have the heater turn on when the circulator turns on, that might be cooling it down before it really has a chance to heat up. To be continued.............
Stay warm, Jimmy