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

OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
Do you know anyone who has used the fish street coil and is confident it's actually fully titanium? I'm nervous it of the quality and if it will leech unwanted metals.

I don't know of anyone using it, but I would be willing to give it a shot if it were me. I use a immersion titanium chiller, and this is basically the same thing. obviously the junctions are brass, so care would have to be taken to keep them out of contact with tank water. I also think that generally fish street does it's best to provide decent products- I would think they would have removed it if they had gotten complaints.
 

justingraham

5000 Club Member
View Badges
Joined
Jul 13, 2016
Messages
5,348
Reaction score
6,709
Rating - 0%
0   0   0
Would this work?
image.jpg


I’m trying to heat and cool with only one pump
 
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
Would this work?
image.jpg


I’m trying to heat and cool with only one pump
I don't think "between" is a valid apex code.
I would code the temp controller using 2 virtual outlets
Then I could control the pump using those virtual outlets as well.

I can help you code it, but I'm not sure I understand your physical setup.
By "to sink" do you mean that you are dumping water to your drain, or is this where you hare getting your hot and cold water from?

If you are dumping water to a drain, that would be a terrible setup, as it would cost a fortune and would be very inefficient. If that's just your source that would be fine
 

justingraham

5000 Club Member
View Badges
Joined
Jul 13, 2016
Messages
5,348
Reaction score
6,709
Rating - 0%
0   0   0
I don't think "between" is a valid apex code.
I would code the temp controller using 2 virtual outlets
Then I could control the pump using those virtual outlets as well.

I can help you code it, but I'm not sure I understand your physical setup.
By "to sink" do you mean that you are dumping water to your drain, or is this where you hare getting your hot and cold water from?

If you are dumping water to a drain, that would be a terrible setup, as it would cost a fortune and would be very inefficient. If that's just your source that would be fine
Id be getting the water from a sink
And putting it back into the main supply water line to the house

And the between isn’t an option on apex it is just a quick way for me to write it down and any help would be appreciated
 
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
Id be getting the water from a sink
And putting it back into the main supply water line to the house

And the between isn’t an option on apex it is just a quick way for me to write it down and any help would be appreciated

So this is about how I would set it up:

Virtual_outlet_heat:
Fallback OFF
If Tmpx11 < 78 Then ON
If Tmpx11 > 79 Then OFF

Virtual_outlet_cool:
Fallback OFF
If Tmpx11 > 80 Then ON
If Tmpx11 < 79 Then OFF

Temperature_controller
If Virtual_outlet_heat = on then on
If Virtual_outlet_cool = on then on

circulation_pump
If Virtual_outlet_heat = on then on
If Virtual_outlet_cool = on then on

but perhaps if you have the ability you should run 2 secondary temperature controllers for heating and cooling to control the ball valves- this would give you a better backup.
 

justingraham

5000 Club Member
View Badges
Joined
Jul 13, 2016
Messages
5,348
Reaction score
6,709
Rating - 0%
0   0   0
So this is about how I would set it up:

Virtual_outlet_heat:
Fallback OFF
If Tmpx11 < 78 Then ON
If Tmpx11 > 79 Then OFF

Virtual_outlet_cool:
Fallback OFF
If Tmpx11 > 80 Then ON
If Tmpx11 < 79 Then OFF

Temperature_controller
If Virtual_outlet_heat = on then on
If Virtual_outlet_cool = on then on

circulation_pump
If Virtual_outlet_heat = on then on
If Virtual_outlet_cool = on then on

but perhaps if you have the ability you should run 2 secondary temperature controllers for heating and cooling to control the ball valves- this would give you a better backup.
The one inkbird I saw has the ability to control hot and cold

But the diagram I have of how I want it to work is fine?
 

ZoWhat

7500 Club Member
View Badges
Joined
Feb 23, 2014
Messages
9,897
Reaction score
17,531
Location
Cincinnati Ohio
Rating - 0%
0   0   0
I could probably save myself $1,000 a year driving no more than 45mph on the highway.... but theres this thing called Quality of Life that we all have to pay the piper for.

If im.going to this much trouble to save money....I'd much rather spend $8,000 for solar on my roof and cutdown my electricity bill bigtime. Friend of mine did that. Owns a Tesla and sometimes puts so much AC back in the grid he get a check some months from the Electric Company


.
 
Last edited:
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
The one inkbird I saw has the ability to control hot and cold

But the diagram I have of how I want it to work is fine?

Yeah, diagram looks fine.
I figured you were using a heating and cooling controller, which would probably be fine- I think it probably provides the same amount of redundancy. so I guess ignore my previous statement about 2 secondary temp controllers
 
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
There is no return from "well the system failed me" .... 110degree water is impossible to come back from. No thanks Bill Nye the Science Guy

Basically every very large (>2000g) system runs a system very similar to this or a heat pump system. They tend to be very reliable, as they require (usually) 2 dedicated electronic temperature controllers to fail, versus the mechanical thermostats that have a set cycle life that you find in electric heaters. You do loose the ability of using multiple undersized heaters as a fail safe, but it is a trade off well worth making.
 
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
How can you tell if it’s titanium and nothing else?
They are made for purposes very similar to ours (usually raising talapia or something similar), so they should work perfectly- you could ask what grade titanium is used, but I'm not sure what use it would be, if they would even know, or if they would be truthful. I would just go for it.
 

Deep dive coral

Well-Known Member
View Badges
Joined
May 30, 2019
Messages
708
Reaction score
1,082
Location
Long Island
Rating - 0%
0   0   0
I'm sorry I'm not follow the drawing. I am trying to figure out a way to do this as well with cold water recirculation for chilling and hot water for heating. I have a tankless system so that is where im getting a bit confused. I can add a zone to my boiler. That is the easy side I believe. The cooling side is where I'm not getting.
 
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
I'm sorry I'm not follow the drawing. I am trying to figure out a way to do this as well with cold water recirculation for chilling and hot water for heating. I have a tankless system so that is where im getting a bit confused. I can add a zone to my boiler. That is the easy side I believe. The cooling side is where I'm not getting.
The cooling is probably not going to be very effective unless you have a chiller for your house- some businesses do, but I have never seen a house with one. However, to do it as the last person who posted a drawing is doing, you would take the cold water from somewhere in your house from a cold water line (probably as far from the house supply line as possible, but possibly before most of your heavy draw lines- like water heaters and bathrooms), and return it at the cold input to the house (probably as close to the house supply line as possible). At that point you have basically turned your cold water line into a radiator, and as long as your house is below 78 degrees you will get some cooling. As an added benefit whenever you use cold water, you get to "pull" some of that cold out. If set up carefully you could basically pre-heat the cold water going into your hot water heater with your tank, thus benefiting both.

BUT, I am not sure how much cooling would actually be achieved. We can do some basic calculations.
the temperature of two mixed fluids is
t = (m1 c1 t1 + m2 c2 t2 + ... + mn cn tn) / (m1 c1 + m2 c2 + ... + mn cn)
where
t = final temperature (oC, oF)
m= the mas of fluids
c = specific heat of substances (kJ/kgoC, Btu/lboF)
t1= temperatures of substances (oC, oF)

We can ignore the specific heat, since we dealing with basically water for both liquids (I know one is salt water, but we are doing an approximation). And for the same reason we can use volume instead of mass. We are also not mixing, so we have to assume that the heat exchanger is 100% efficient, which it is not, so these are best case numbers. But with those assumptions, we can say:
temp of tank final = (temp of tank initial x volume of tank + temp of cold tap x volume of water used)/(volume of tank+ volume of water used)

assuming your cold tap is 50 degrees F, you are taking a shower (which is ~20g), you have a 200g tank, the tank is at 80 degrees F, and we plug those numbers in,

We get a final tank temperature of 77.3 degrees Fahrenheit- but that is best case- you wont get that - which is why to me a cooling circuit that relies on your cold water tap is not worth it. Unless you keep a cool house and have copper water lines and are using the whole line as a radiator, I don't think it is worth it.

If you want cooling I would run a cooling loop past your whole house ac duct. or run a heat pump for your tank (which is more efficient than heating the water with gas. or you can just use a chiller.
 
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
What size chiller you tr think is needed for a 600g or so system. In NY. I was ry thinking of doing g a DIY window unit.
The titanium heat exchanger would work with a window unit- I would just get the largest they have, as there is not much price difference.
In terms of chiller sizing, if you are going with aquarium specific ones I have no idea- It depends heavily on how conditioned the space is that the tank is in.

Ideally I would have gone with something like this https://www.hayward-pool.com/shop/en/pools/heatpro-120k-heat-cool-ahri-hp31204t
But the $3000 dollar price tag on the heating and cooling heat pump units is a bit much for me. Also I don't really need 120,000 BTUs, which compared to the 4000ish BTUs of a aquarium chiller is a bit much. I think a minisplit could be modified to work for far less, but it would take some research/DIY
 

Deep dive coral

Well-Known Member
View Badges
Joined
May 30, 2019
Messages
708
Reaction score
1,082
Location
Long Island
Rating - 0%
0   0   0
The titanium heat exchanger would work with a window unit- I would just get the largest they have, as there is not much price difference.
In terms of chiller sizing, if you are going with aquarium specific ones I have no idea- It depends heavily on how conditioned the space is that the tank is in.

Ideally I would have gone with something like this https://www.hayward-pool.com/shop/en/pools/heatpro-120k-heat-cool-ahri-hp31204t
But the $3000 dollar price tag on the heating and cooling heat pump units is a bit much for me. Also I don't really need 120,000 BTUs, which compared to the 4000ish BTUs of a aquarium chiller is a bit much. I think a minisplit could be modified to work for far less, but it would take some research/DIY
I have a 1/3 hp chiller sitting in my garage and another 1/4 hp as well. If I decided to go the titanium exchanger route and spit between a window unit and the boiler how would that actually work?. The boiler is sending hot water and the AC unit is sending freon. I'm far from a heat and AC guy that's why im asking. I'm wondering if I'm better off using a heat exchanger for heat and then a titanium coil for chilling? Any thoughts.
 

justingraham

5000 Club Member
View Badges
Joined
Jul 13, 2016
Messages
5,348
Reaction score
6,709
Rating - 0%
0   0   0
So your saying it’s not worth it to chill my tank with cold water?
Right now I use two computer fans to keep my tank u set 80 degrees I figured cold water is a lot less noisy
 
OP
OP
DBR_Reef

DBR_Reef

Active Member
View Badges
Joined
Apr 4, 2016
Messages
373
Reaction score
303
Location
Rochester, NY
Rating - 0%
0   0   0
So your saying it’s not worth it to chill my tank with cold water?
Right now I use two computer fans to keep my tank u set 80 degrees I figured cold water is a lot less noisy
Depends on how it is set up- if it is set up to use your houses plumbing as a radiator then sure, it will probably work, as long as you keep your house below 75 degrees.
If you're trying to rely on the cold water usage, then probably not, unless you use a lot of water.
 
Back
Top