Hot water heater and recirculator pump

[Davej]

Looks like Home Depot has GE and Lowes has Whirlpool. Both offer 6, 9,

12 year models. I was thinking of getting the 9 year (40 gallon) to be one step above the cheapest. Since I am switching over from electric to gas I wonder how I might estimate the monthly reduction I should see on my electric bill?

I also bought one of these some time back and it has been sitting in the cardboard box;

Since I will be relocating the water heater this may be the right time to try to install the circulator scheme. This implies a loop, so I'm thinking of running a smaller pipe back to the pump from the farthest point (kitchen). The main run is 3/4". I guess the return to the pump could be 1/2" or even smaller?

[trader4]

Impossible to say. Among the big unknowns is how much hot water you use. It's going to be different for a family on one versus one with 5 kids. Unless you have a seperate meter for the water heater or some way of knowing how much electricity it used, you don't have a place to start. The savings, if any, will come from the fact that nat gas is usually a cheaper source of energy that electric.

1/2" should be fine. It doesn't have to move a lot of water quickly. I would not go below 1/2". If you're using copper, that is the smallest copper std size typically available, unless you go with tubing instead of pipe, which I would not do.

Many of these pumps just return the hot water via the cold water line. That saves a pipe run, especially convenient for old work where you don't have access. Downside to that is that it puts that tepid hot water into the cold line where the sink or any other location on that run will pull it. Not so good if you want a drink of water and get a glass of stanky, tepid water from the water heater. So, I like the idea of the seperate return line. You could also consider putting it on a timer so that it doesn't recirculate all night when rarely used. Also, insulate all pipes as you will have a heating loop, losing energy.

[Evan]

This doesn't sound like a project for you to be working on at all, aside from the fact that you thought copper water supply lines are available in sizes less than 1/2" which aren't, its a different type of copper tubing in smaller sizes which aren't for use in main supply piping runs but for single device connection...

Second you seem to think that you need some sort of circulator pump but you don't, not if you don't need one now... Just pay to have the gas lines extended to where your present hot water tank is located rather than fussing around with installing water lines and a pump and back- flow preventers in the right spots so you aren't circulating "nasty hot water" from inside your hot water tank into your cold water piping -- not to mention that such schemes generally cost more in fuel than running water for a second to get hot water out of the tap as it is constantly heating some of the cold water it is drawing in out of the loop of pipe...

You really can't estimate anything about the reduction on your electric bill, you can guess what it might be by looking at the energy useage info on the hot water heater and divide the annual kWh usage by 12... Without knowing how much hot water you are presently using you can't really figure out what any savings will be by switching from electric to gas as there is a pretty steep investment cost which has to be paid for and any ROI will be a while in coming...

~~ Evan

[N8N]

I never considered that an option, because isn't heated water technically not considered potable? I often draw a glass of water from, say, the bathroom sink if I already have a glass and don't feel like walking all the way back to the kitchen.

nate

[HeyBub]

Correct on the potability. There are bacteria that grow in the water heater that you can't BUY on the open market. Some of them ( Legionella pneumophila, the "Legionnaires Disease" culprit), can kill you.

Never consume water from the water heater. Don't use it to wash off food.

[clare]

Not out of the ordinary to see 3/8" soft copper tube used for return, and the circ pump on a timer.

[clare]

>

Same situation here. Sewage based on water - and it costs more to get rid of it than it does to get it.

[trader4]

I didn't see any indication of anyone going off half-cocked. except Evan, as usual. He's jumping to the conclusion that the guy is relocating the water heater location to be able to use gas. Reading the post again, there is absolutely no connection betweent the two that I see.

All I see is that the poster wants to replace an electric water heater with a gas one and that he wants to install a circulation pump because hot water is not currently getting somewhere it's needed fast enough. And for that he gets jumped on?

[HeyBub]

>>

Cities get very clever about raising money. My city recently imposed a fee on the amount of non-porous property we have. That is, house, driveway, garage, and the like. It's supposedly dedicated to drainage improvements. In my case, the fee is included on the water bill and is substantially larger than the water and sewage charges combined.

[Robert Neville]

That sounds great. We have a recirc pump on a timer, but I'd like to change that to an on-demand system as you described. Any links to the relay?

[Stormin Mormon]

I've never heard this. I consume hot water now and again. Do you have a credible web site perhaps? If there's truth to this, I'd like to know.

Christopher A. Young Learn more about Jesus

.

Correct on the potability. There are bacteria that grow in the water heater that you can't BUY on the open market. Some of them ( Legionella pneumophila, the "Legionnaires Disease" culprit), can kill you.

Never consume water from the water heater. Don't use it to wash off food.

[clare]

Unless the temperature of the heater is set at a "sensible", not "safe" 160 degrees+ F.

[clare]

>>>

You in Waterloo Region too?

[Steve Barker]

if the water heater is in the basement, you won't even need the pump. Just bring a return line from the farthest point back to the drain fitting ( 't' and all that), and gravity will do the rest. A non sprung (flapper) type check valve in the final vertical line prevents the half cooled water from coming back when you open the faucet.

[HeyBub]

Er, no. I'm in Houston. The city used Google Earth maps and some clever software to calculate the amount of non-porous property at my home.

They offered exemptions for certain conditions. One was a ditch. If you were served by a drainage ditch instead of storm sewers, you got exempted. In my case there is a drainage ditch - more like a canal - behind my house. I protested the original computation, claiming 1/2 of the property drainage for my land went to the ditch, not the street storm sewer.

Denied.

[trader4]

Seems 140F is more sensible. Safe from legionnaires and safer from scalding....

Maintain domestic water heaters at 60=B0C (140=B0F) and water delivered at the faucet at a minimum of 50=B0C (122=B0F). Where these temperatures cannot be maintained, control LDB growth with a safe and effective alternative method. Also see What to consider in the system design.

[Steve Barker]

all these years i've been making hot chocolate with the tap water.... hmmmmmmmmm.. it's a wonder i'm not dead.... LMMFAO!!!

[clare]

140 is NOT safe from Legienella, according to several studies. !60F IS.