Hot Water Question

[Arks]

Arks, in our case the pump is tiny, you don't need to move a lot of water to keep it warm and son-in-law and I wrapped the pipes to retain heat. A side benefit is that it keeps a bit of water moving so pipes don't freeze in winter. Our hot water tank is only 60 gallons for everything so not a lot of water being stored/heated but a large burner like the tankless type to kick in when needed.

By coincidence, the latest project on This Old House included installation of a hot water circulating pump. They said as the hot water circulates 24/7, it cools down on the return trip to the hot water heater, so the water heater has to come and off a lot more often, as hot water continuously leaves and new colder water comes in. This does lead to higher fuel costs and more wear and tear on the water heater.

To get around this, they simply put a lamp timer on the pump, so it only comes on to circulate the hot water around the time they need hot water quickly, for daytime hand washing and for bath time. No need to circulate it all night when people are sleeping.

 

[JimBoone]

To get around this, they simply put a lamp timer on the pump, so it only comes on to circulate the hot water around the time they need hot water quickly, for daytime hand washing and for bath time. No need to circulate it all night when people are sleeping.

Even simpler, the Watts pump I use has a timer built into the pump, at different times I've used it both ways in different seasons of the year.

In stock form it uses a thermostatic valve under the sink at the far end of the line. That valve feeds the hot back into the cold line, but only enough until the hot side is warm and then the valve closes, not really a steady flow of water. With the same thought if a person used a 3-pipe system you would only need a small return pipe and you could throttle down the rate of return with a valve, the object being to keep it warm.

https://www.amazon.com/Watts-500800...&hvlocphy=&hvtargid=pla-4583863979503191&th=1

 

[Arks]

Even simpler, the Watts pump I use has a timer built into the pump, at different times I've used it both ways in different seasons of the year.

In stock form it uses a thermostatic valve under the sink at the far end of the line. That valve feeds the hot back into the cold line, but only enough until the hot side is warm and then the valve closes, not really a steady flow of water.

Brilliant. I've ordered one!

 

[Arks]

...it uses a thermostatic valve under the sink at the far end of the line. That valve feeds the hot back into the cold line...

I got mine installed today. Pump with timer at the water heater and thermostatic valve under the sink at the far end of the line. Works great. Water comes warm out of the hot tap in less than 2 seconds of opening the tap, and gets warmer quickly, up to hot.

Only problem I see is that, since the hot water is fed back into the cold water line, the cold water is warm when I turn it on, so I have to run the water a while to get cold water. No big deal. Great device and fairly easy do it yourself installation, though I HATE working under sinks, laying on my back, can't see, trying to get wrenches into tight spaces. Horrible. I can't believe some plumber hasn't invented a system where you assemble everything out on the countertop then just snap it into place!

 

[JimBoone]

I HATE working under sinks, laying on my back, can't see, trying to get wrenches into tight spaces. Horrible. I can't believe some plumber hasn't invented a system where you assemble everything out on the countertop then just snap it into place!

If it was too easy, we wouldn't need plumbers, but some just nap on the job.

 

[Anon Inn]

Not pipes - it did.

Our tankless heaters are mounted under a roofed porch. One year a cold snap did freeze and burst one of the Takagi heaters. Since then I tent them with vented reflectix and plug a small heater underneath when temps dip into the 20s. We don't get below freezing temps often here.

 

[Arks]

We don't get below freezing temps often here.

Lucky you! When I woke up here in north Arkansas this morning we had snow on the ground and it was -2F/-19C outside! This is the price of living south of central Canada!
It's fun to sip coffee, eat homemade Christmas cookies, nap, etc. I don't really mind the cold, within reason. Two below is NOT within reason! I'm not as tough as Gillum.

 

[gillumhouse]

Lucky you! When I woke up here in north Arkansas this morning we had snow on the ground and it was -2F/-19C outside! This is the price of living south of central Canada!
It's fun to sip coffee, eat homemade Christmas cookies, nap, etc. I don't really mind the cold, within reason. Two below is NOT within reason! I'm not as tough as Gillum.

It was -2 here, going up to +8, back down to -2 over Christmas Eve/Christmas and climbed into the teens yesterday. It is now a balmy +45. My usual save the waterlines routine when temps go single digits is to set my alarm to the time of lowest predicted temp, get up, start washing machine, go back to bed. Washing machines give the Italian Salute when the power is off. Had already opened the doors under the sink & jacked the gas heater in the kitchen - now I closed the kitchen door to keep the heat in there. Once the power came back, the space heater in my bathroom was cranked & that door closed (all faucets were already on fast drip - oy the water bill this month!) and turned on heat in the upstairs bathrooms. Started the washer - that load had a few extra cycles over the next few days. No pipes froze. My entire city had no power for that 8-hours. (Sunday I had a call from a man in the town north of us asking how much I would charge for them to come take a shower - their pipes had burst. Offered the room but they just needed showers - had heat. N/C just come. It seems I am known as the "port in the storm".)

 

[Arks]

My usual save the waterlines routine...

Around here, the routine is to leave vulnerable water taps open a little, so there's a trickle of water running slowly but constantly to keep the lines from freezing, because the city water lines never freeze, buried too deep.

In a small town near here last week so many people left water running all night that they drained the town water tank and the system lost pressure, so they're all under a boil order now! I'm thinking those people don't know the definition of the word trickle!

 

[gillumhouse]

WV frostline is 32 inches. Our waterlines are buried 48 inches deep. We put our faucets on a medium to fast drip. We do not want to pay the water bill for more than that.

 

[SDnewbie]

Am contemplating a Sensei 11.1 GPM Commericial 199,000 BTU Propane/Natural Gas Indoor/Outdoor Tankless Water Heater for our 5 bedroom B&B. Have a 40 gallon in the basement for the kitchen and 1 shower. And comments/suggestions??

 

[gillumhouse]

I cannot comment because I have a 30 gallon gas water heater. I do not know what kind it is, but my brother showed me his tankless, on demand water heater he installed in his house in Florida when I was there last week. He says he never runs out of water. His is mounted on the wall in the laundry room. You will not be at the mercy of the electric grid!

 

[SDnewbie]

So how many people do you regularly serve with the 30 gallon water heater? We are looking at 20 max so am I overthinking this? Don't want to spend the $1,500 if I can get by with less...

 

[gillumhouse]

I have 3 rooms so up to 6 guests plus me. I wash clothes in cold water. The water heater is gas. One bathroom has, in addition to the 48-inch shower stall, a claw-foot tub in the ensuite bathroom. A LARGE claw-foot tub. I do not remember ever running out of hot water.

 

[SDnewbie]

Thanks for this. Will make sure I don't overbuy!