Plumbing what is the best fix?

[spankomatic]

A friend of mine just bought a new (1960') house. When he takes a shower and someone else in the house takes a shower he gets COLD water. I know this is sometimes common and wondering what the BEST plumbing fix is. He is considering installing a tankless water heater just for that shower. Is there a better way?

Jim

 

[maytagbear]

Tankless is certainly a way to go---

but it can be costly, particularly if a gas line is not close by. I would not even think about an electric tankless, unless there was no gas within miles.

A less expensive option might be a new shower valve (faucet)...a temperature/pressure balancing valve, also known as an anti-scald valve. However, that might mean re-tiling......

Or, if your friend could just change his shower time.

Lawrence/Maytagbear

 

[sikiguya]

I know nothing about plumbing but..........

can't they shower together? ;-)

 

[jasonl]

I'm no plumber but from what I know

If a house has 1/2" piping throughout, you will get that effect when flushing a toilet and turning on another faucet. Most houses are run with 1/2" to cut costs

If you run 3/4" and 1/2" to the fixtures, both can shower.

Showering together is an easy fix.

 

[perc-o-prince]

We had a similar problem because there was a decrease in hot water pressure overall. BTW- this is also why the spin-tube DW didn't fill enough and we had to pour a gallon or so in for each fill. It was a timed fill and the water ran too slowly.

When we replaced the old boiler w/ a new one and it vastly inproved. The water doesn't stay at its full temp, but it doesn't go all cold any longer.

Chuck

 

[cornutt]

A house that age probably has galvanized iron plumbing. By now, that stuff is so clogged up with lime and minerals and corrosion that you probably can't get a straw through it.

 

[circlew]

The pressure balanced valve is an excellent idea. However,if the pipes are clogged or too small, the overall volumn of water will be reduced. I've addressed this issue in my current renovation by having the plumber use 3/4" or larger lines when they serve more than one fixture.

As for galvanized piping, that was obsolete for water supply lines around here by 1950, however it was still being used for drains until somewhat later. My old plumbing system was copper supply with C.I. and galvanized drain lines. Therefore, I doubt a house built in '60 would have galvanized for supply, unless that was local custom, or a rather inexpensive house. The galvanized drains in my house clogged easily, and also developed leaks, as they rusted out.

 

[toggleswitch2]

I agree. The main plumbing arteries needs to be 3/4" of an inch diameter.

The branch to the three (or 4) bathroom fixtures (in one batroom then shoould bee off of a 1/2" branch.

Ditto the kitchen. Only a 1/2" feed to the sinks AND the dishwasher

Also if you connect any washing machines to a faucet with a "y" connector, one may want to be sure there is a check-valve on each by that sink to ensure that the cold doesn't sneak back in to to the hot side.

 

[jasonl]

My brother in law just built a little guest house in back of my MIL's house. He used 3/4" PEX throughout. He was saying that the hot water is almost instant and flushing a toilet or turning on another faucet doesn't effect whoever is taking a shower.

But being the stinker that I am and my house is 1/2" throughout, I wait for Helen to start her shower then I open a hot water faucet somewhere and she gets a blast of cold water.

 

[rp2813]

Our house is over 80 years old and almost all of the galvanized pipe under it is original. Water pressure is lousy because it's 1/2" pipe and some sections are way corroded, like the part that leads to the kitchen faucet.

We have our worst issues with water pressure when the sprinkler system outside is running. That sucks pressure away from everything else, enough so that the upstairs toilet's fill valve won't always kick in when you flush while sprinkers are on. We can sort of get away with running hot water somewhere else while one of the showers is going, but we try not to, and for sure you don't want to shower while the washer or dishwasher is running.

I think galvanized was used for residential construction in this part of the country at least into the 1960's.

 

[brisnat81]

For low cold pressure, we cheated in one house that we lived in. There was PVC from the meter to the Gal at the house, we put a T piece in and ran PVC around to the tap at the back of the house near the hotwater heater. From then on things were much more tolerable. Cold was Gal, Hot was copper.

Those pipe diameters are pretty large, In Australia most new houses have a 3/4 main into the house (Usually PVC) and then internal piping is usually all 1/2" copper including the main runs and for hot and cold. The idea for the small diameter hot water runs, is that you waste less water bleeding the cold out whilst you wait for the hot.

We have a heat exchange hot water heater that is limited to a flow rate of 9L per minute. We can still run two showers at once without any issues?

 

[sudsmaster]

I think part of the solution would be to use 3/4" copper for the hot and cold main runs, and 1/2" for the shorter runs to each fixture. The hot water lines should be well insulated, esp the 3/4" pipes. Granted, it won't keep them hot overnight but it will help to keep them at least warm during regular use later in the day.

There are different types of water pipe insulation. The cheapest looks like it's simple polyethylene foam. The more expensive - and thicker - synthetic rubber (EPDM?) foam is probably more efficient at keeping hot things hot.

 

[spankomatic]

My friend and I thank you all for the very helpful imput. My friend did just learn during the recent kitchen remodel that they do have galvanized plumbing and was pretty glogged up like Cornutt thought. It was also suggested to them that they could have them "blasted" clean. Anyone ever try this? Would a hot water circulation pump help the maintain the hot water presure during showers?
Jim

 

[whirlcool]

In our house the main bathroom is quite a distance away from the hot water tank. It takes about a full 90 seconds for even room temperature water to reach the fixtures.

How does a recirculation pump work?

 

[combo52]

OLD IRON SUPPLY LINES

I have never heard of trying to clean old iron pipes they would probably fall apart. New copper or plastic pipe is the only real fix.

 

[alr2903]

Whirlcool, a recirculation pump keeps the water moving in the loop, all hotels and motels most likely have the system. Our house was built in 1953 our pipes are nearly stopped up with minerals, I discovered this when our water heater was changed out, we also had a dishwasher installed, but no need to fool with the old pipes they simply removed the single flex fit, and added a T, the plumber well advised me to keep in mind that if you start messing with old pipes they can keep crumbling and leaking. Less is more unless you want to spend big bucks. alr2903

 

[sudsmaster]

I would not attempt to "blast clean" old galvanized steel piping. It's clogged because it's rusting from the inside out. Trying to blast the rust away will only weaken the piping further. The only real solution is to replace the clogged piping, preferably with something that doesn't rust, like copper or plastic. In my town, plastic is against code so it would have to be copper.

Another reason to avoid replacing old steel with new steel is that galvanized coatings contain small amounts of lead. The lead makes for a more corrosion resistant coating, but who wants lead in their drinking water? Newer piping may eliminate most if not all of the lead, but then the piping probably will corrode even faster. Copper fastened with lead-free solder is the best way to go.

 

[sudsmaster]

PS-If the galvanized is all clogged up it's probably on its last legs anyway. Better to replace it now, during the remodel, and avoid an expensive piping failure that could cause a fair amount of water damage if it happens in the wrong place.