I put a heating coil in the heat exchanger of my old boiler a while back connected to my electric hot water tank. Gravity feed worked but not well enough.
I ran across this little 12v hot water pump for about $20 on ebay. It's submersible too. It arrived today and I hooked it up. I'm using a 12v DC 1 amp power pack from an old set of computer speakers to power it. The pump maxes out at 0.5 amp. I'm using a Honeywell temp switch to turn it on and off but as it turns out it never cools down enough to shut off. I guess it'll shut off when the fire goes out.
The setup is kind of temporary but now that I know how well it works, I'll make it permanent.
After tweaking the flow with the shutoff valve, I got water temp over 130 degrees F into the water heater with a flue temp of 350F. As the tank heats up I expect I'll get even higher temperature.
133.5F in this pic.
Here is a pic of how I connected it to the boiler.
Electric hot water tank connections,
I ran across this little 12v hot water pump for about $20 on ebay. It's submersible too. It arrived today and I hooked it up. I'm using a 12v DC 1 amp power pack from an old set of computer speakers to power it. The pump maxes out at 0.5 amp. I'm using a Honeywell temp switch to turn it on and off but as it turns out it never cools down enough to shut off. I guess it'll shut off when the fire goes out.
The setup is kind of temporary but now that I know how well it works, I'll make it permanent.
After tweaking the flow with the shutoff valve, I got water temp over 130 degrees F into the water heater with a flue temp of 350F. As the tank heats up I expect I'll get even higher temperature.
133.5F in this pic.
Here is a pic of how I connected it to the boiler.
Electric hot water tank connections,
