Is there an easy way to heat my electric hot water tank with my boiler coil? I would like to hook up a pump maybe to circulate when the boiler is hot so therefore I will have lots of hot water in the mornings. What controls , piping is needed??
Dhw, heating electric water tank with boiler coil
- Thread starter wantstoburnwood
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Nofossil
Moderator Emeritus
I'm not sure what 'boiler coil' you're referring to, but lots of folks use sidearms to heat their hot water tanks. A search will turn up plenty of threads. You'll need a tempering valve on the hot water tank outlet to prevent scalding.
Nofossil I have a coil in my oil boiler which is hooked up in a series with my econoburn . I get hot water by thermosiphon through the electric hot water heater. I'm thinking of heating dhw like a super stor system.
Nofossil
Moderator Emeritus
wantstoburnwood said:
Thermosiphon is great - does that not meet your needs?
You could simply add a potable water circulator (Laing makes a small stainless model) to circulate water from the bottom of the hot water tank through the oil coil and back to the top of the hot water tank. You would want the mixing valve as mentioned before. Getting 180 degree water out of your sink faucet is unacceptably dangerous, and it can easily happen. I use the Honeywell AM101 for that purpose.
You could control the circulator with a simple aquastat so that it runs any time that the wood boiler outlet is above some reasonable setpoint. To get more efficient operation, disable the circ with another aquastat when the water coming out the bottom of the hot water tank is above a lower temp - say 130 or so.
smokinj
Minister of Fire
No fossil I don't have thermo siphon. My mistake . I have the water pass through the coil in the boiler and then to my hot water heater as I run hot water . If I run too much water when the boiler is down it gets really cool.So I'm hoping to hook a pump up that runs when the boiler is hot and I have 40 gallons of reserve dhw when the boiler is cool.
Anyone know a way to hook the thermostat in the water heater up to circulator for on/ off and keep the thermostat in the water heater operational for summer use . The water heater is 220 volt and the circ. is 120 volt
Gooserider
Mod Emeritus
Option 1. Use a relay - presumably with a DPDT switch to change the thermostat out line from the heating element to the relay coil.
Option 2. Add a second 110V thermostat and use that to switch the circulator.
Gooserider
Option 2. Add a second 110V thermostat and use that to switch the circulator.
Gooserider
Thank you Gooserider for your reply. I hooked up the circ pump to the lower thermostat on water heater so it seems fine. I will hook up a DPDT switch for the same thermostat to give me summer ( water heater on ) and winter (only thermostat on for circ control on for winter operation).
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