Heating large tanks with your gas hot water heater. Save 40% on energy cost!

[Blue Carbon Reefing]

Ok all. I have everything I need to get this done. My main question right now would be is there any reason why I can't or shouldn't use a drain line instead of the return line like DBR did his for the heat exchanger? My main display has 6 X 1" drain lines. 4 are in use all the time and 2 are only used as emergency. Essentially it is a double bean animal drain setup with one set of 3 pipes on each side. My drain pipes go directly over my 2 X 50 Gallon Hot water heaters so I was planning on plumbing in the heat exchanger salt water side to one of the 1 " drain lines and back to my basement sump. This would drain to my first compartment of my sump where I kept my electric heaters anyway before the 1st temperature probe. Is there anything with this setup that sounds like it would pose a problem? Thank you!

 

[DBR_Reef]

Ok all. I have everything I need to get this done. My main question right now would be is there any reason why I can't or shouldn't use a drain line instead of the return line like DBR did his for the heat exchanger? My main display has 6 X 1" drain lines. 4 are in use all the time and 2 are only used as emergency. Essentially it is a double bean animal drain setup with one set of 3 pipes on each side. My drain pipes go directly over my 2 X 50 Gallon Hot water heaters so I was planning on plumbing in the heat exchanger salt water side to one of the 1 " drain lines and back to my basement sump. This would drain to my first compartment of my sump where I kept my electric heaters anyway before the 1st temperature probe. Is there anything with this setup that sounds like it would pose a problem? Thank you!

I always get nervous about putting any restriction on a drain line, but a double bean animal is a pretty forgiving drain, so I would say it is fine. And I’m assuming you are using one of the full siphon drains. My only concern is if the temperature of the water in your sump would reflect the water in the tank- not sure on that one- I use temp probes in the sump ant the tank to make sure they don’t vary.

 

[Blue Carbon Reefing]

I always get nervous about putting any restriction on a drain line, but a double bean animal is a pretty forgiving drain, so I would say it is fine. And I’m assuming you are using one of the full siphon drains. My only concern is if the temperature of the water in your sump would reflect the water in the tank- not sure on that one- I use temp probes in the sump ant the tank to make sure they don’t vary.

That was the plan was to use one of the full siphon lines. My only thought was if the heat exchanger would get dirty quicker because of overflowing food instead of cleaned up water going back to the tank. I am hoping there is enough flow going through it that it isn't going to cause too much maintenance cleaning all the time. Have you taken yours apart yet to clean it? I am definitely going to use ball valves, unions, and shark bite fittings to make sure it is easy to disconnect to clean when ever needed.

 

[Blue Carbon Reefing]

ok all. everything is installed and working very well. I need some plumbing help though because no matter what I do I cannot get the two ends of the heat exchanger that have the hot water from the hot water heater running through to stop dripping. It is dripping about 1 drip every 30 to 60 seconds. I have taken the brass fittings going into off twice and put new teflon tape on them twice wrapping it about 5 to 6 times around each. Is there any tips I can do to get a line like that under pressure to not drip? What do plumbers do? I can take pictures or a video if needed.

Here is a picture of the log from the APEX. It appears the heater is coming on for 7 to 10 minutes and cooling back down for only about 12 to 20 minutes. It is definitely off more longer than on but it makes me see how fast my tank is losing heat. I am going to start to look at insulating certain tanks in the system. The whole system is estimate of 1250 gallons which contains multiple tanks and sumps all connected. I have the pump coming on at 77.0 degrees and going off at 77.5 degrees. I didn't want more than a 1/2 degree swing in temp and also didn't want the pump turning on and off every 5 minutes. On average it appears to be turning off and on every 20 minutes (from on to on cycle). Do you think that is too often?

 

[DBR_Reef]

ok all. everything is installed and working very well. I need some plumbing help though because no matter what I do I cannot get the two ends of the heat exchanger that have the hot water from the hot water heater running through to stop dripping. It is dripping about 1 drip every 30 to 60 seconds. I have taken the brass fittings going into off twice and put new teflon tape on them twice wrapping it about 5 to 6 times around each. Is there any tips I can do to get a line like that under pressure to not drip? What do plumbers do? I can take pictures or a video if needed.

Here is a picture of the log from the APEX. It appears the heater is coming on for 7 to 10 minutes and cooling back down for only about 12 to 20 minutes. It is definitely off more longer than on but it makes me see how fast my tank is losing heat. I am going to start to look at insulating certain tanks in the system. The whole system is estimate of 1250 gallons which contains multiple tanks and sumps all connected. I have the pump coming on at 77.0 degrees and going off at 77.5 degrees. I didn't want more than a 1/2 degree swing in temp and also didn't want the pump turning on and off every 5 minutes. On average it appears to be turning off and on every 20 minutes (from on to on cycle). Do you think that is too often?

Ideally you probably should be using pipe dope to seal the threads- that will probably solve your problem. That being said, I used thread tape because I was taking it on and off and wanted the lubrication without the mess. I last time I put it on to test it it had a drip about as frequent as yours. I meant to take it off and use thread dope, but the weeks passed and other things always took precedence- it eventually sealed itself. But you may not want to procrastinate your drip away.

The time on and off seams perfect to me- not heating too fast and not constantly turning on and off.

 

[Blue Carbon Reefing]

Thanks @DBR_Reef ! Props to you for this video/thread. I have been thinking about doing this for a while and watching your video gave me the confidence that it could be done and still be safe. It has been a cold and brutal winter and my electric bill was getting way out of hand. I am going further insulate the lines and see if that has any additional effect but the lines are pretty short runs. 2 feet out and 2 feet back in.

 

[DBR_Reef]

Thanks @DBR_Reef ! Props to you for this video/thread. I have been thinking about doing this for a while and watching your video gave me the confidence that it could be done and still be safe. It has been a cold and brutal winter and my electric bill was getting way out of hand. I am going further insulate the lines and see if that has any additional effect but the lines are pretty short runs. 2 feet out and 2 feet back in.

looks like you have basically the perfect setup for this, and looks nice and clean. You'll have to let us know how that pump holds up- it looks like one of the chinese brands?

 

[Blue Carbon Reefing]

looks like you have basically the perfect setup for this, and looks nice and clean. You'll have to let us know how that pump holds up- it looks like one of the chinese brands?

Thanks, this is why I chose to use the drain line over the return line. it goes right over the hot water heaters so it was perfect. It is dead silent. I have it on the 1st of 3 settings which is also the lowest. I think it operates at 43 Watts. I opted to go for a new Chinese brand pump as opposed to a used pump Grundfos. I always have hard time buying used equipment in this hobby. I bought an infrared thermometer since I didn't have one. I thought it would help see how much of a drop in the hot water I am getting through the heat exchanger when it is running. so far the water is 120 degrees going in and about 107 going out on average. it seems like it is dropping about 13 degrees and going back to the cold water inlet.

 

[Dubs83]

Quick question

Could I use PEX and push connectors instead of copper to tap into my water heater? For example, tap into hot water supply to the kitchen sink using a copper T. After T, brass ball valve into a push connector then run pex into the fish room and back to the cold water supply line to the water heater. This way, I can keep the heat exchanger in my fish room and not worry about copper being destroyed by salt in the fish room

 

[Blue Carbon Reefing]

Quick question

Could I use PEX and push connectors instead of copper to tap into my water heater? For example, tap into hot water supply to the kitchen sink using a copper T. After T, brass ball valve into a push connector then run pex into the fish room and back to the cold water supply line to the water heater. This way, I can keep the heat exchanger in my fish room and not worry about copper being destroyed by salt in the fish room

You can absolutely use Pex. My house was built new and I did this without any copper only pex. Here is a link to the overview of how I set it up. Let me know if you have any questions.

 

[Dubs83]

You can absolutely use Pex. My house was built new and I did this without any copper only pex. Here is a link to the overview of how I set it up. Let me know if you have any questions.

That’s perfect! Thanks for sharing. Can you show me exactly how you wired the motorized ball valve?

 

[Blue Carbon Reefing]

It honestly is super easy. There two wires to the ball valve. It doesnt matter which is power and which is ground. I tested it both ways and it works both ways so you cant mess that up either way. I could take some pictures if you need some.

 

[Dubs83]

It honestly is super easy. There two wires to the ball valve. It doesnt matter which is power and which is ground. I tested it both ways and it works both ways so you cant mess that up either way. I could take some pictures if you need some.

No, that’s fine. Seems clear enough. Last question, does the pump and ball valve turn on and open at the same time? In other words, are they plugged into the outlet on a controller or do you off set them slightly?

 

[Blue Carbon Reefing]

I have I have them both set up to my Apex. They both come on at the same time. The electronic ball valve opens in a matter of 3 to 5 Seconds. So I have them both set to come on at a certain temperature and set to go off at a certain temperature and I've never had a problem. Right now on my system which is over 1200 gallons the pump will come on and run for about 5 to 6 minutes and it will be off for about 30 minutes in the winter and off for an hour or more in the summer time before coming back on for five to six minutes to heat the tank back up a half a degree.

 

[Pigpen]

You can also do something like this where its all mounted together and can do heating and cooling . this is how we build the ones we sell .

 

[justingraham]

You can also do something like this where its all mounted together and can do heating and cooling . this is how we build the ones we sell .

What do u use for cold water?

 

[Pigpen]

cold tap water if your in an area that has cold tapwater .

 

[justingraham]

How does it work does the water come from the left or right? And what is the center piping for looks like the hot and the cold water meet?

 

[justingraham]

cold tap water if your in an area that has cold tapwater .

Yeah mine isn’t that would be to good to be true

 

[Dubs83]

cold tap water if your in an area that has cold tapwater .

Hmm looks like I’d just need another motorized ball valve and tap off any cold water line for cooling. Where does the cold water line go after passing through the heat exchanger?