Hot Water Circulation ?

[Charles Hans]

I have been trying to gather information on the Auto circ 2 system made by the Laing company, made for circulating hot water to distant faucets, like the ones most distance from the water heater, say on the second floor bathrooms. They make some valid points about saving water and I am wondering if anyone here has insatlled this system and how it works for you. I don't want to blow $200.00 on something that does not work as advertised. If you have not heard of it here is a link to their website.
www.autocirc.com (http://www.autocirc.com/)

[Bill Webber]

Hi Charles,

I have no experience with the unit... but that is no reason to prevent tossing out some random thoughts! :)

When I was a youngster, my dad had 'tourist cabins' in New Hampshire. There was a circular pipe than ran hot water to all the cabins and the pipe returned to the water heater. A 'circulator pump' was turned on in the morning to make certain the pipe was filled with hot water. This has nothing to do with what you are tring to do.. just goes to 'I understand your problem..

The circulation system you point to will certainly work. One draw back of the system is that if you get up in the middle of the night and want a cool drink, you will be getting warm-to-hot water out of your cold water faucet until you run it for awhile.

If the problem mentioned above is acceptable, and the bathrooms you are trying to speed hot water to is above the water heater, I would simply connect the hot water line to the cold water line (at the remote bathroom end) and see if the convection circulation alone would produce satisfactory results. I'm betting it would. Seems like such a good idea, I may try it myself. Tell me how it works out! :)

YMMV...:D

[Norman Hitt]

Although more expensive initially, if you have natural gas in your house, a tankless water heater in the outlying area will give nearly INSTANT hot water, AND will save both water, and energy, (just another thought).

[Randy Meijer]

Since I see'em being highlighted for installments of "This Old House", so I assume that they work. But you may want to consider the economics. I did some "rough" calculations for my G/F's house and if my assumptions were anywhere near correct the payback based solely on reduced water usage was about 20 years. And that was for putting a pump in the kitchen. She also has a bathroom on the far side of the house from the water heater and it would need a separate recirculator for that room as well. Since she lives alone, hers is an extreme case. As you add more people to the mix, the payback time decreases. Another thing to consider is that I did the math based on it being a DIY project. If you are going to have to pay a plumber and an electrician to do the installation, payback time goes way up!! :mad:

Forgetting about the economics, many folks think it is worth the expense just to avoid the inconvenience and discomfort of waiting for warm water....especially if you live in Duluth, MN. It's not such a big problem in Texas. :D

[Karl Laustrup]

Charles, I'm with Norman on this one. I think a tankless water heater for your remote locations would be much more economical in the long run.

That's why I'm installing a tankless unit in our new home. It will power the bathrooms and laundry. I would be using another for the kitchen, but I had just had to purchase a new 40 gallon tank heater in October, so I decided to re-use it to power the kitchen. If you didn't see the plans for our house the kitchen and baths are on opposite ends of the house. About 60+ feet between. That would be a lot of water down the drain waiting for hot water.

My runs are only going to be about 10' in the kitchen and the longest run for the tankless unit will be about 15-20'. Not quite instant, but shouldn't be but about a gallon or so down the drain before the hot water gets there.

Karl

[Jim Becker]

I'm going to do the tankless in our planned...err, soon to be planned...home addition. I don't want to schlep hot water that far and the present system is just fine for the existing fixtures.

[Hal Flynt]

I have a tankless and won't go back. (I probably would install 2 smaller units, one under the kitchen and one under the baths).

Now, back in the 60's my uncle was in the plumbing supply business and had instant hot water in the upstairs faucets (as well as throughout his house). He showed me a 1/4" flexible copper line that attached to the hot watter supply line in the faucet with the longest run from the water heater and it ran down to the cold water supply side of the water heater. Convection kept water flowing in a constant loop. This increased cost of heating was at least partially offset by not having to run the faucet until the water got hot. No pumps were involved. He did it while building, so in a retrofit, it could prove to be more costly than acouple of vales and a length of 1/4" copper tubing.

[Bill Lewis]

I too have been looking at using a recirc pump for our house. There is another company that makes one that also has a manual or a motion detector (PIR) switch that activates the pump. Then the pump cuts off thermostatically.

This is the one that was shown on one of the TOH shows that Randy mentioned. It is made by the TYCO company. Sorry I can't seem to find the web site address right now. I got the inital info from the TOH site.

If I were to do one, and i probably will, it would be strickly for convienence and comfort, not expecting any real payback. I just hate waiting on the water.

[Bill Lewis]

Hah, found it on the TOH site!

www.tyco-hvac.com (http://www.tyco-hvac.com)
D'Mand Systems from Taco Inc.
1160 Cranston Street
Cranston, RI 02920
tel. 401-942-8000
fax 401-942-2360

[Charles Hans]

I am looking more for the convienence than the payback factor, I would need to install a point of use heater in each of the three upstairs bathrooms, if I understand correctly. Right now we have to run water for about a minute to get hot water to a lavatory sink upstairs, this gets a little tiresome and I am just trying to find out what is available. I am familiar with the convection systems and that would not be possible in old construction without going to great length to accomplish it. The lower floor bathroom,and kitchen are no problem, due to the location of the water heater in the basement

[Bill Lewis]

Charles,

Both units that we have collectively posted are virtually identical in function and operation. I suspect that they will both work quite well as advertised.

What Bill Webber suggested, is really the passive equivalent of this pumping system. Basically just looping the hot and cold supplies together, but letting physics (convection) do the work vs. a pump.

I like the idea of putting a motion sensor on the pump so it activates when it is needed as opposed to always maintaining the temperature in the hot water line, though this too has its advatages.

My situation requires that I have a second, or remotely mounted PIR, so that the pump is triggered in the kitchen, and not just the bathroom where it is located. I just haven't gotten around going any further with it.

Some side notes and anecdotes and thoughts on recirculation systems.
1. They've been around for years especially in commercial applications like hotels. Mostly three line systems, a hot, a cold, and a hot return, or some variation of this.
2. My neighbor the plumber went a little crazy and plumbed his house with 3/4" three line system throughout his house. You shoulda' seen the plumbing in that place.
3. When they remodeled the bathrooms in my building at work and "upgraded" the faucets to ones with low flow, and hand sensing we now have no hot water in the bathrooms. They need a recirc pump!
4. The furthest bathrrom in my house takes well over a minute to get hot water to it.
5. This is still a less expensive option campared to a tankless heater and easier to retrofit.

[Charles Hans]

Bill, your thoughts are similar to mine, I think that going tankless would cost me a lot more to install even by doing it myself, I would have to run electrical supply to locations of the units and that is tough in finished construction. I hust finished running some recessed can lights in the ceiling of the kitchen, and it wasn't a lot of fun not being able to appraoch it from above. anything is possible I guess, it's just a matter of how much trouble you are willing to go to.
Thanks for your input. One of my concerns was the reliability of the pump that they supply.I think I will go for it.
Thanks

[Don Wurscher]

I have had a Grundfos Confort Series Instant Hot Water System installed in my house for 4 years now, and am very pleased with it.

It has a circulation pump (with timer) mounted on top of the hot water heater (hot side) and a temperature sensitive valve which mounts under the sink/tub etc. The system uses the cold water line as the hot water tank return.

The only draw back is that it takes awhile to get really cold water out of a faucet that has not been used for awhile.

The unit with 2 valves cost me $243.00, 4 years ago.

DLW