Saving big bucks on hot water!

[geekinc]

I am using an ApplianceLinc to control the pump on our hot water recirculation system.

 

Before the automation, it was on a timer, and naive me had the timer running in the mornings and evenings during off-peak hours to save on the electric bill. The problem was during the cold months(cold for us in AZ, at least...) I would hear the hot water heater working frequently when the pump was on and that was wasting gas like crazy.

 

Our first winter bill was almost 4 times the normal gas bill!

 

Now I have my ApplianceLinc controlled by the ISY thru my ELK keypads through out the house and the water is pumped only on demand. Our bill the last couple of months has been normal, and dropping like a rock since I haven't turned the heat on since early Feb.

[jhoulihan]

I'm planning on triggering my recirculation pump with motion sensors in the bathrooms.

 

I had another idea to convert to an istant hot water system joined with a small 20 gal hot water heater and recirculation pump so there would be no delay in hot water to faucets.

 

Anyone know if this would work?

[aLf]

Do any of you guys have a recirculating system that works well as add-on? I just put in a Navien On-Demand HWH and albeit better on gas, you have to wait quite a while for hot water. I was thinking that a recirc system would be nice. Any ideas?

 

aLf

[tome]

Do any of you guys have a recirculating system that works well as add-on? I just put in a Navien On-Demand HWH and albeit better on gas, you have to wait quite a while for hot water. I was thinking that a recirc system would be nice. Any ideas?

 

aLf

 

Seems like demand hot water and recirc are mutually exclusive. If you have a whole house demand water heater then it defeats the purpose to put a recirc system in place and make it work when there is no demand.

 

Usually, people put small on-demand systems close to water source so it cuts down (a little) on the wait. Demand systems don't make water instantly. Quick, but not instant...

 

Tome

[aLf]

Tome: I understand your point, however, Navien has a built in recirc pump. Actually two. The first options recirc through a Mickey Mouse internal tank which is about two quarts (how far is that going to go)? The second is a port on the bottom of the unit which is the "return" from an outside recirc system. It then pumps water at a scheduled time to keep hot water at the faucets. With their program I think a guy could keep the cost down. I was just wondering about an inexpensive add-on type recirc that could be retrofitted now. There are no return pipes at the faucets now. One could do some sort of add-on in the basement just below, say the shower. I have seen many after market systems, but am hesitant to cut pipe until I hear from someone that it actually works. Until then I'll waste water letting it warm up. These tankless heaters are excellent in every way except for the fact that it takes twice to three times as long to get warm water at a faucet. Thanks again, I'll be happy to listen to anyones thoughts.

 

 

aLf

[Illusion]

Yep

 

http://www.gothotwater.com/

 

Have had it and used it for about 14 years now every day. Works great as a retrofit. I have a manual button on the kitchen faucet (the furthest fixture in the house). I also have a contact closure module there that is activated via the ISY

 

IF:

 

I have my bathroom floor heater on

And

I turn on the light in the shower

 

This preheats the pipes when I am going to get in the shower.

 

P.S. With the quick install kit, you do not even need to cut pipe!!

[aLf]

Illusion:

 

I'd love to talk with you about this. Maybe PM me and I'll call n my $. This looks GREAT.

 

aLf

[tome]

FWIW, my brother-in-law installs the Nibco Just Right Valve in homes (both new and old) and swears by them (not at them ).

 

http://www.nibco.com/cms.do?id=2&pId=345

http://www.nibco.com/assets/JRInstall.pdf

 

I don't have personal experience with it myself but he says it works and is easy to install. It is made for a traditional hot water tank system, however.

[aLf]

tome:

 

Thank you! This too looks like it should have an opportunity. Great Stuff! I'm amazed at all the info... But then Michel and his team do nothing but attract knowledgable folks on every subject. My ISY has given me so much good info on so many things. Thanks again.

 

aLf

[Zick]

I'm planning on triggering my recirculation pump with motion sensors in the bathrooms.

 

I had another idea to convert to an istant hot water system joined with a small 20 gal hot water heater and recirculation pump so there would be no delay in hot water to faucets.

 

Anyone know if this would work?

 

Thanks geekinc & jhoulihan for the ideas!

We just built a new house and couldn't quite figure out why our gas bill was also very high.

We never had a recirculator before but now we do and I also had it setup on a timer running during the times we were home. But I noticed the water heater kicking on constantly compared to our older (less efficient) one we used to have.

 

So I put in an 2473 Outletlinc with the circulator plugged into it and put a 2420 motion sensor in the rooms we mainly use hot water (master bath & kitchen) so the only time it will turn on is when we're in those rooms.

This should cut the time the circulator runs by almost 75%.

 

[rswilkes]

Going along with triggering the recirc pump is there a way to monitor the on / off cycles of a gas hot water heater. I could determine the gas usage before and after that way.

[IndyMike]

Hi rswilkes,

 

The easiest method I can think of to detect the on/off of a water heater would be to detect when the exhaust fan is activated (assuming you have on).

 

If your exhaust fan is 24V (mine isn't) there is a IOlinc kit for switching on low voltage inputs: IOlinc Low Voltage Kit.

 

If you have a 120V fan things become a bit more involved. If you have access to the motor power leads (mine are exposed with spade lugs) you could "slip" a current transformer over the lead to sense the ON state. Since this is a current output, you would need to size a resistive load to produce a voltage in the "sense" range of the IOLinc. This will depend on the current transformer you select (current ratio from the input to the output) and the current consumption of the fan motor.

 

The most reasonably priced current transformers that I've see recently are available at Brultech. Their range is overkill (40 Amps) but the price is right:Micro40 CT

 

As a caution, I do not have a lot of experience using the IOlincs in a sense mode. By the documentation this should work - I don't have direct experience and therefor defer to others "skilled in the art".

[Brian H]

The CT-800 mentioned in these tutorials. Outputs a closure with current. You would not have to mess with voltages on the I/OLincs sense terminals as there would be a closure. Note the sensor Input actually has a DC voltage on it internally. Sensor input maybe a poor choice of description as it is more like a closure input.

Examples show a furnace and a few other things. I would think around one of the fans 120 volt power wires would work fine.

 

http://www.cocoontech.com/portal/articl ... nt-sensors

[IndyMike]

Brian,

Very Nice! I hadn't seen this item.

 

My 120V blower motor is rated at 2.2 A. Seems like quite a bit of power for a blower (likely a peak rating).

 

Since the CT-800 switches at 1A, rswilkes will need to ensure that his motor draws at least 1 amp continuous.

 

Thanks Brian - I have some uses for this,

 

IM

[WayneW]

Since the CT-800 switches at 1A, rswilkes will need to ensure that his motor draws at least 1 amp continuous.

If the current is not sufficient to trip the sensor, you can often increase the number of loops of wire passing through the sensor to "magnify" the load.

[IndyMike]

If the current is not sufficient to trip the sensor, you can often increase the number of loops of wire passing through the sensor to "magnify" the load.

 

Good point Wayne,

 

Obviously I'm a bit too fixated on my particular water heater configuration. The exposed lead length to the fan motor won't allow multiple loops through the CT. Simple matter of splicing an extension lead to allow the multiple loops.

[paulw]

We have a Laing recirc pump in the kitchen which is a very long run to the water heater. The Laing will cycle on and off based on water temp at the sink.

 

Use a button on a keylinc to turn it on (appliance linc at the pump), the isy turns it off in 20 minutes. Yes, there is no instant hot water when you walk into the kitchen, but in a couple of minutes it is hot. Works for us.

[Morris Hansen]

To monitor my 2 furnaces and 2 water heaters ( all natural gas) I built a simple 1wire network and put a sensor near each flue. When ever the burners turn on, the flue temp rises very quickly and then when they turn off, you can watch the temp decline.

 

After monitoring my water heaters, I found one of them was cycling 6-7 times a day. It was over 14 years old so just replaced it.

 

If anyone is interested in the graphs of data, I can pull some reports tomorrow and post.