Replies

1. 
   rjw | Jan 07, 2003 09:53pm | #1

   Off the top of my head:

   Time how long to fill a 1 quart container at that faucet.  Time how long it takes for the hot water to get there.

   Say 15 seconds for 1 quart; then 1 min for 1 gallon.

   Say it takes 2 minutes for the water to get hot - thus, 2 gallons are "wasted."

   Then, ah, lets see.  Cost to heat 2 gals.  Ah.  Er.

   Never mind {G}

   _______________________

   "I may have said the same thing before... But my explanation, I am sure, will always be different."  Oscar Wilde

1. 
   riverr1 | Jan 07, 2003 10:38pm | #2

   Bob,

   I follow you on that, and it makes sense, but if someone has broken this down to water and btu costs, it sure would help! 8-)

   I think the water here is insignifacant as a cost issue. The issue here really is the energy cost and loss, and good social citizenship. I'm confident my parents are not alone in this boat, and if savings could be estimated in total, I sure the outcome would be significant.

   Don

2. 
   geob21 | Jan 08, 2003 01:58am | #3

   Why do you need to heat hot water?

3. 
   nigelUsa | Jan 08, 2003 03:03am | #4

   Its more down to getting hot water now! I often use the laundry tub to washup because its within 7' of the water heater. kitchen sink is about 50' of pipe and takes a while to get hot water. Its like power windows, don't need them but sure is nice!!

   Water heater should be nearest the most used sink if possible.

1. 
   JohnSprung | Jan 08, 2003 03:19am | #5

   Near the point of greatest use is a good idea.  Mine's on the ground floor, next to the laundry, under the master bath, and 10 ft. from the main kitchen sink.  The ground floor is a good idea for two reasons.  WH's leak sometimes, so downstairs you don't get water running along a floor joist and dripping down in another room.  WH's are heavy, and in earthquake country it's best to keep heavy things down low.

   -- J.S.

4. 
   cybersportSS | Jan 08, 2003 03:19am | #6

   I build custom homes 10,000 sq ft typical.  We put in a recirculting line so you can get instant hot water throughout the house.  There are a couple of different ways to achieve this but for the most part it should be done in the roughing stage of the game.

   Alex

   "free advice is worth what you pay for it"

1. 
   HammerHarry | Jan 08, 2003 07:20am | #7

   And remember, if you are calculating heat "lost", you will have to consider how many degree days of heating you require in your climate, and the cost of heat, because the "lost" heat is lost to your house, and therefore is heat you do not need to supply in another way; or, depending on your location, it would be extra heat you need to remove with an air conditioner.  And you'll have to add in the extra heat generated by trying to put a number to this.

   I think you'll find the biggest cost is the Frustration factor.

5. 
   TLRice | Jan 08, 2003 04:33pm | #8

   Don,

   Several considerations in where to locate a water heater:

   -location of the fuel supply

   -access to an exterior wall or chase, chimney or flue stack to vent

   -location of a floor drain or sump

   -plumbing layout of the CW supply

   -location of points of use

   -response time (in some non-residential applications, response time is Code limited)

   I relocated mine to a central portion of the house to address the last two issues and since I was in the process of rerouting plumbing lines and gas lines, the other issues were not important to me. I had to core a hole through a concrete wall to run the vent and I added a sump in floor near the new location. Were I not in the process of reconfiguring a lot of these things anyways, I would not have done it. Insulating the pipes, although highly recommended, will not help in the response time. A recirc line/pump makes for great response, but will waste more energy. The energy savings in moving the DWH to a more central location will be insignificant.

1. 
   UncleDunc | Jan 08, 2003 10:21pm | #9

   Thanks for the list of factors, Tim. I can use that.

   You say "Insulating the pipes ... will not help in the response time." If you measure response time by waiting till the water in the pipes is cold despite the insulation, that's true, but it's easy for me to imagine a time window during which the hot water in the old, uninsulated pipes would have cooled off too much to be usable as hot water but the hot water in insulated pipes would still be warm enough to be usable. Someone who frequently needs hot water in that time interval would perceive a dramatic improvement in response time.

   I like the recirculating loop idea myself, but there's no doubt that it is more expensive and complex than just insulating.

1. 
   riverr1 | Jan 08, 2003 10:39pm | #10

   Thanks to all for your opinions, thoughts and considerations. I'm guessing that no amount of debate will sway my fathers choice. Funny thing is, if he had thought of this, if might have gotten done. He's a competitive man.

   Don

1. 
   Dant45 | Jan 10, 2003 08:37pm | #13

   Well, competative or not, he owns the house.  DanT

1. 
   riverr1 | Jan 10, 2003 08:54pm | #15

   Dan,

   Excellent point! ;-0

   Don

2. 
   TLRice | Jan 10, 2003 04:26pm | #11

   For intermittent, but frequent use, insulation is a big plus, and if the pipes run in a semi-conditioned space like a basement or open crawl, it is very much recommended. I insulate all pipes, cold and hot for several reasons, thermal, noise, and condensation.

   The recirc loop is not really all that expensive. A competent plumber can install a recirc loop that works on gravity, though most invole a small (hydronic small zone circulator will do) pump. If you have a tankless, you can't use a recirc loop. I once saw a system, that mounts, say under a sink in the most remote bath, has a small pump and an adjustable timer and can be set up with push button or an occupancy sensor. When you are going to need hot water, you push the button. It recircs from the hot supply to the cold supply for a minute or two, pre-warms the hot supply line without any water wasted. Cost about $250.

1. 
   GregGibson | Jan 10, 2003 07:36pm | #12

   I've always wondered if someone, somewhere might be working on a water heating system that works on microwaves.  Picture running a network or coil of PVC pipe through a microwave oven.  The oven would run whenever the water flow was activated.  Who knows, it might be viable.

   The idea comes from my old home, vintage about 1952, which is now one of my rentals.  The water heater is rather distant from the kitchen.  Whenever I needed to wipe down a counter or clean up a kid, I would wet a cloth with cold water and put it in the microwave for about 12 seconds.  The result was a steaming hot cloth.  Try it - surely it saves on that gallon or so of waste water, waiting for the tap to run hot.

   Greg.

1. 
   BillHartmann | Jan 10, 2003 08:53pm | #14

   What you describe is an tankless or on demand water heater. They are available now with resistive heating. Resistive heating would be cheaper and more efficient than the microwave.