instant hot water

[Ashful]

Three of our sinks are on a long run from the boiler room, and thus take a very long time to get hot water. All three are in a tight grouping, near one another at the end of this line, making me think that a small water heater placed near the point of use would be a good solution to the problem. We are talking about 50 feet of 1/2" line, so less than 1 gallon of stored cold water in the line, between appliances and the boiler. I'm wondering if there are some small 2 - 3 gallon water heaters that I could hang from a joist in the end of the basement near the point of use of these three sinks, and feed from a single 230 volt line, similar to the "Instant Hot" type products you might normally see mounted under a single sink.

I know that new construction would have a return and circulator, for situations like this, but this ain't new construction.

 

[Ashful]

Doh... should've asked Google.

https://www.homedepot.com/p/Rheem-P...18371?MERCH=REC-_-pipsem-_-NA-_-204318371-_-N

 

[WinterinWI]

If the feed lines are exposed in the basement, it would be pretty easy to make it recirculating. I'd think that would be cheaper in the long run but could be wrong, you'd have to run the numbers. Electric water heaters cost a fair amount of $ to run, but so do electric motors. Could get away with a fairly small motor for this though. Would be interesting to see how the 2 options compare.

 

[Ashful]

Would need some guidance on setting up the recirc system. Water heaters I know, but never lived in a house with recirc. Yes, all lines are exposed in basement ceiling.

 

[bholler]

What I did in my old house was the smallest electric tank heater available under the kitchen which was a long run. I feed it with hot water from the boiler so it really didn't cost much at all to run and it was much cheaper to buy and hook up than an on demand electric.

 

[Highbeam]

I own the white plastic cube 5 or 7 gallon version also sold at Home Depot for the shop sink. It’s been flawless but I feed it non chlorinated, naturally soft, iron/manganese/sulfur, free well water at 40-60 psi. It makes no noise, has an easy to adjust thermostat, and uses 120 volt power from a switch. Takes about 30 minutes to rise from 60-120 degrees with 1500 watts.

It just sits in a shelf and is fed with two little braided stainless 1/2” flex lines.

In your application you will start sucking hot water but refilling the water heater with a slug of cold water. The bigger this tank, the less likely you will notice it get cooler before hot water begins feeding from the main hot tank.

 

[festerw]

Something like this might be worth investigating. Never used one myself but the price is right.

https://www.amazon.com/dp/B000E78XHG/?tag=hearthamazon-20

 

[Ashful]

What I did in my old house was the smallest electric tank heater available under the kitchen which was a long run. I feed it with hot water from the boiler so it really didn't cost much at all to run and it was much cheaper to buy and hook up than an on demand electric.

This is exactly what I was intending to do, but in the basement crawl space directly under this sink. Crawl space temperature likely averages 65F +/- 10F all year, and it would be fed from my existing hot water line.

I am also running softened, non-chlorinated well water, and had figured on a 6 gallon can to absorb the < 1 gallon “slug” of cold water in the line.

 

[EatenByLimestone]

I'd just wash my hands with cold water. This project seems like a lot of work for minimal benefit.

There's still 2.5 months of weather warm enough to sail in.

 

[Ashful]

I'd just wash my hands with cold water. This project seems like a lot of work for minimal benefit.

There's still 2.5 months of weather warm enough to sail in.

Actually, I have to move 7 full suits of sails just to get at the lines where I’ll be installing this tank, but that will also enable me to run a new dedicated circuit for the espresso machine. Currently, I have to power down the pour-over machine to power up the espresso machine, since they’re both very big draws on the same circuit.

... and it’s not about washing hands! It’s about having hot water to rinse the portafilter between shots, or rinse the coffee carafe after a pot of coffee has been poured into my work thermos!

Sailing has been a bust since early July, but we’re just coming into what I consider my second season, fall sailing! Around here, we have good wind and spring and fall, mid-summer is light air.

 

[EatenByLimestone]

Oh, so its coffee related. Completely justified! Of course, if you're going to move the sails, you should check them. You know you just stuffed them in the sail bag last time you used them. Best way to check them is to spread them out fully, like with a halyard. While you've gone to the trouble to run it up...

 

[Ashful]

Got a big event tomorrow, which is causing me to miss a beautiful race day, with a forecast for a nice stead 10 mph wind. T’would be a perfect day to get one of the kids out on the race course, so don’t rub it in!

I might get a boat out on Sunday, as I’ve already completed the mowing for this week. We only have maybe 8 weekends of weather suitable for the kids, in our wet boats. I can go another month past that, but leaving the kids with the wife on a Saturday never wins me any points.

 

[semipro]

Something like this might be worth investigating. Never used one myself but the price is right.

https://www.amazon.com/dp/B000E78XHG/?tag=hearthamazon-20

This works. We've installed and used one.

 

[begreen]

We've had a recirc system for many years supplying the upstairs bathroom in our old house. Works great. I put the return line plumbing in for it when we remodeled that bathroom in 2003. Has a tiny Grundfos timer pump that gets the job done.

 

[EatenByLimestone]

Had a rainbow reflecting off the lake today.

 

[Ashful]

Had a rainbow reflecting off the lake today.

But there’s something wrong with that picture: you’re on land! [emoji14]

Going to try to take one kid sailing tomorrow. Wind forecast is only 6-7 mph, which is lame, but maybe I can get the kid to take the tiller. Today would have been fantastic, but had a volunteering commitment.

 

[EatenByLimestone]

There wasn't much wind, lol.



It's supposed to be down to 38 tonight! Warm days are numbered!

 

[mellow]

38! Glad I am not in NY. Its almost 90 here today, plenty of pool heating days left

 

[fbelec]

if you run a 2nd water pipe with a small taco pump or equiv. the pump will be control by a strap on aquastat so when the return water reaches temp the pump shuts down. the little taco pump only draws 70 watts. verses 1500 watts when the small water heater is running. then insulate the pipes. done.

 

[begreen]

if you run a 2nd water pipe with a small taco pump or equiv. the pump will be control by a strap on aquastat so when the return water reaches temp the pump shuts down. the little taco pump only draws 70 watts. verses 1500 watts when the small water heater is running. then insulate the pipes. done.

That's what we have, but by Grundfos. Uses under 10w and just runs occasionally during the day and not at all from midnight to 7am.

 

[Highbeam]

if you run a 2nd water pipe with a small taco pump or equiv. the pump will be control by a strap on aquastat so when the return water reaches temp the pump shuts down. the little taco pump only draws 70 watts. verses 1500 watts when the small water heater is running. then insulate the pipes. done.

So that 1500 watts to the secondary heater is to reheat the water that cooled after being heated once by the main water heater. I propose that there will be at least as much heat loss from the insulated pipes that you are keeping hot all the time with a circ pump as the secondary tank burns to maintain the secondary tank hot. After all, if there was no heat loss then you wouldn't have a need for a circ pump or a secondary water heater. So with a circ pump your main water heater will fire more often plus you will pay for the circ pump power.

If your main water heater is much more efficient than the secondary water heater then maybe the additional energy loss of hot pipes and circ pump is worth it.

 

[Ashful]

I've been debating the same in my head, highbeam and fbelec, but have come to conclusion it likely doesn't matter. The spread in the numbers is likely very small, assuming either is done properly.

More importantly, I've realized my original description of that line was not accurate. The three sinks and one dishwasher that are tapped off that run are not all down at the end of it, as I had suspected. The line takes a more circuitous route which places the three appliances at a substantial distance from one another along the line, despite them being located very close to each other in our floor plan.

So, this particular layout easily favors the circulator option, and I will be installing that sometime this winter. First I need to get about 20 sails moved out of the way, I had hung them from the rafters in that area of my crawl space when we moved in, and they're now blocking my route! This may be a Christmas/New Years project, as there are a few other items I'll likely roll in with it.

BTW, the manifold festerw posted is a very cool idea, it used your cold water line as the recirc line. If you don't mind having a lot of warm water stored in the cold water supply line, it's not a bad way to go. If I didn't have plumbing experience, or it were a location difficult to run a recirc line, I'd give this more consideration.

 

[fbelec]

i would also think about how long the tank will last vs a pump. pump is cheaper easy to replace and when it goes there is no flood

 

[billb3]

I'd just wash my hands with cold water. This project seems like a lot of work for minimal benefit.

There's still 2.5 months of weather warm enough to sail in.

Wasting quite a bit of water to get hot water is no biggee when you're on a well like me , but if you have city water and also have to pay for sewer that adds up pretty quick. I'm considering moving my in the basement water tank closer to the kitchen sink and bathroom for this same reason.

 

[Ashful]

For me, it’s not the wasted water. It’s the wasted time, which may add up to maybe six hours per year! I don’t want to spend 60 hours waiting on hot water, over the next ten years of my life.