We had our carport turned into a room for our handicapped son and the plumber came out to plumb the bathroom. Now where we always had plenty hot water downstairs and upstairs the water downstairs only gets lukewarm and when someone is taking a shower upstairs cold water runs through all the faucets downstairs when you turn them on. Before we were able to take hot showers upstairs and downstairs at the same time. No one knows the answer and the plumber says it hooked it up right. We don't have the new room faucets hooked up yet so we don't know if we will even have hot water in it or not. Please, Please someone help us.

Did your plumber put in new shower / shower valve in this new addition ?

All I know is that he ran the plumbing for the shower, sink and toilet. Another man put the shower in but he hasn't got the faucet on yet.

Is that new shower finished and fully functional ?

The shower is just installed without being functional as of now because they don't have the shower sprayer installed or the turn on knob.

What kind / brand of shower faucet was installed in that new shower ? Delta ?

Yes, it is a Delta

Delta faucets come with temporary cartridge. That cartridge is nothing else but a plug to prevent dirt from entering interior of the body of the faucet. Therefore, and as a result, Cold water is allowed to enter Hot water side and to flow throughout your house. Since Cold water has more pressure than Hot water, you are getting luke-warm, or cold, water throughout the house.

Temporary cartridge is designed to stay there during construction to prevent damage to the fully functional cartridge. This cartridge is installed after shower walls and floor are tiled and sealed.

Some less experienced plumbers are not aware this detail.

To correct your present problem:

1. Close water to the whole house
2. Remove temporary cartridge (plug)
3. Locate real cartridge ( should be inside the paper faucet box )
4. Insert new cartridge and trim. Leave handle in Close Position
5. Open water service to the house

This will solve your problem. If you are reasonably handy, you could do it yourself in few minutes. Only tools you need is medium size channel locks and screwdriver.

Or call back the original plumber and ask him to correct his installation.

Let me know how you did. Milo

Thank you we will certainly get this checked out and I will let you know. Thank you so much.

I finally got ahold of the contractor that put the delta faucet in our shower and when I told him what you said he knew immediately that you had the answer and he was really impressed he said you was right on top of it and he wondered why the rest of them wasn't. He came out today and put the other one in but the water still isn't heating and he said the mixer or whatever it is called doesn't want to go in right so he has called a plumber to come out this afternoon but they are sure you are right so thanks a million and may God Bless You.

Milo I was going to rate but it will not let me You must spread some Reputation around before giving it to Milo Dolezal again.

Excellent troubleshot Milo you are a live saver, Thanks.

Best Regards,
John