Query: Quick hot water at shower with no recirculation pump

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larrymcg

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This is a curiosity, not a problem.

We have been in this house for several months and there is a gas fired hot water heater in the garage. It takes a long time for hot water to get to the bathrooms because there is no recirculation pump. However, hot water appears at the shower head of the master bath in about 10-15 seconds and this bath is about 50-60 feet from the water heater. It takes a long time for hot water to appear at the sinks in the same bathroom.

Also, there is no flash heater.

How can hot water get to one place quickly even though it is far from the heater?

Curiously,
Larry
 

larrymcg

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I think of a small pipe being able to deliver a small flow. Unless the pressure is high. But the pressure wouldn't be higher in one pipe versus another.
 

Reach4

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I think of a small pipe being able to deliver a small flow. Unless the pressure is high. But the pressure wouldn't be higher in one pipe versus another.
http://www.allianceforwaterefficiency.org/WorkArea/DownloadAsset.aspx?id=2312

pix_1.GIF

Suppose your faucet draws 1 GPM of hot water with 50 feet of pipe between the faucet and the WH. You would wait 16 seconds to get hot water with 3/8 PEX vs 75 seconds if piped with 3/4 inch type L copper.
 

Smooky

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Most hand sinks have a flow restrictor or an aerator. It takes longer to flush the pipe of the cold water. The aerator or flow restrictor could be stopped up too and that could increase the time to flush the pipe even more.
 

larrymcg

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We have two baths back to back - the master bath with two sinks and a shower and the guest bath with one sink and a shower. I've found that if I run the master shower to get hot water (which happens quickly), the other sinks and the other shower still take a long time to get hot water. So it's seems clear that the master shower has its own hot water line. Everything else is on a common line.

I think we have this figured out!

-- Larry
 

Jadnashua

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IF done very carefully, in some situations, you can get the water to circulate without a pump. It takes careful planning and running of the pipes, but it can be done, at least in some layouts.
 

hj

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quote; think we have this figured out!

Maybe, but maybe not. Plumbers do NOT waste time and material running a separate hot water line to a shower, UNLESS it is closer to the water heater than to a hot water line going elsewhere.
 
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