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something is not right

Hi all,
I recently had some re pipe work done ,and had a new water heater installled.The hot line from the water heater is 3/4" cpvc
piping that runs a length of 27' at which point it reduces down to existing 1/2" type "L" copper piping that runs 5' in length,and for supplying the following fixtures:,(kitchen faucet swivel type handle hot/cold,tub/shower hot/diverter valve/cold, bathroom faucet hot/cold)TProblem: to get hot water at any one fixture mentioned above it takes a good 30+ seconds.To switch to cold water once good and hot takes litteraly just an instant though. I can reduce the 27' hot side piping in length downn to 19'. Might this help,or eliminate altogether this hot water delivery problem. I have been getting estimates from reduce the 3/4 pipe to 1/2",but more saying the only way to fix this is with a recirculating pump. There are dwellings on the same block here with the same pluumbing layout with a longer hot side pipe run and get hot water in a snap at the opening of the hot side.
So,i ask the pros here? Reduce the run of pipe from 27' to 19'?
change the pipe size? etc.
I have attached 4 picture of present set up if they help
Picture 01: hot water line (bottom) from WH
Picture 08: 3/4 pipe hot side on outside then going uderground and back up on other side of exterior wall going back inside
Picture 06: inside and under kitchen sink
Picture 05: another view under kitchen sink

Thank you to all for your help and advice!!

Re: something is not right

The hotwater lines run outside --- underground --- then back up outside - then enter the living space?
When the hot water is not being used it will cool off ( standing loss ).
Having the pipes run outside and under ground will be heatsinks drawing the heat out the pipes sooner.
The longer the pipe run the more cool water has to be displaced .

Very different setup.

Re: something is not right

I agree with Canuk, I've never seen a hot water pipe come off of a water heater, go outside, underground, then back in again. Then again I've heard a lot of stuff on TOH that I've never heard before. :eek: That's where your losing your hot water.

Re: something is not right

Thank you Canul and Sten for your replys.

I thought this forum is supposed to help not tell someone how bad of a setup they have...laughing all in good fun.. These were my thoughts right away looking this over.

If you look at picture 2 (06) you can see on the exterior block wall,and the unpainted outline of where a run of 1/2" type"L" copper piping was run and also notice how it ran exposed over the back step area and the length of the copper pipe was all foam insulated. I was thinking of running the 3/4" cpvc this way? or the cpvc just under the back step..or go back to copper? If so stay with 3/4 or back to the original 1/2 it was years ago?

Let's see the alternative for that to run the entire hot water line inside would be run it from the WH up through the attic back down into the bathroom,or jack hammmer up the width of the kitchen floor for running pipe lengths to bathroom fixtures. Are you all suggesting that to keep all piping inside.

Thanks again for all the help!

Re: something is not right

I doubt the length of 27 feet or the 3/4 - 1/2 inch are the problem .
We can't see what the limitations are --- but if there is a way of getting the supply lines inside would be more ideal . Is there no way to run the lines from the tank through an inside wall ?

Re: something is not right

Canuk sure that can be done,but for this project no in the wall pipes.Plus a big factor as I have mentioned in my first post is that there are other dwellings on this block (infact the house next door to me) with the same floor plan,plumbing layout etc. that already have the hot water line running partly on the exterior wall and part of the piping running underground.
I would just like to solve this problem with those parameters and factors to work around.From that alone i know there is a solution to this via different pipe routing outside. I have been thinking of running some 3/4 either above the ground at that back step area or just under the back step? Anybodys thoughts on that?

Thanks all again

Re: something is not right

The volume of water in a 3/4" pipe will be more than double the volume of a 1/2" pipe. But, of course, the amount of water that can be delivered by the 3/4" pipe is also greater. Having the kitchen sink and bathroom group on a 1/2" pipe is pushing it. 3/4" is better in terms of total flow, but worse in terms of the time it takes for the cooled water to be flushed out.

An alternate for you to consider is the recirculating systems sold by Taco and Grundfoss that utilize a two-pipe system, and don't require the installation of a third line for recirculation.

Re: something is not right

rdesigns thank you for the reply.At the poinnt were both the hot and cold go to 1/2" pipe to feed the the only bathroom, and kitchen sinks the volume/water flow is wonderful. For the delay in getting hot water at any 3 fixtures (tub/shower is 3rd) I think I will go ahead and cut out 8' of the 3/4" cpvc bringing the 27' of 3/4 cpvc piping down to 19' in length,and connecting a 3/4 or 1/2 pipe ? to the bottom of the insulated vertical pipe lengths already on the exterior block wall. (see attached picture).And either run the pipe to be connected under the concrete back step or above it ?
Suggestions about this?

P.s. For some reason i was able to attach the pic yesterday today it won't. It's the first pic i attached in yesterdays post
_08 only pic of 4 that has a back door in it.

Thank you

Re: something is not right
tech526 wrote:

I think I will go ahead and cut out 8' of the 3/4" cpvc bringing the 27' of 3/4 cpvc piping down to 19' in length,and connecting a 3/4 or 1/2 pipe ?

You may be disappointed with what little change this will make.

Going from 3/4" pipe to 1/2" pipe for just 8 feet will will reduce the amount of cooled water in the line by only about 1/10 gallon, so you might notice hardly any reduction in time for the hot to arrive at the bathroom faucets.

Re: something is not right

rDesigns thank you again,

What about getting rid of the 8'of 3/4 pipe which would still reduce the length to 19' on hot side,but re connect that cut out section with 3/4" cpvc piping instead of 1/2.

This is getting crazy. I mean as I have mentioned before, on this block ,and the house right next to me has their hot water line running from the WH going outside ,and underground and works great...just a turn of the handle and hey I feel hot water,, and they have a very similar plumbing layout (within a foot in length on hot water line)

The question not asked is said to be the dumb one. So I will ask this one. Would a larger capacity WH in anyway effect this situation in a good way?

I need AsK this old house out here...laughing

Bay Area..Ca
Re: something is not right

I dont think a larger water heater would not make a difference.Are the other homes using the same cpvc and copper lengths as your home? Are your pipes insulated the same and is your water heater set to the same temperature as the other homes? Also,did you check the other homes yourself at the same time of day as yours without anybody running any water for several hours to get a true comparison?


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