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No Hot Water, New Water Heater?

My house is very old, it still the old house with blocks on the bottom. I just replace a new heater last winter, but I still do not have any hot water in my shower. I went through the whole winter showering in cold water. This year, well, its way to cold to continue through another winter like this. There is hot water in the kitchen sink, but will take up to 10-15 min before it gets hot. The sink in the restroom will not even warm up. What would be the problem? I have replace the hot water gasket in the shower but with no luck. The water heater is at max. Is it the pipes?? If there is water, can it have no hot water though?? Can someone help?? Thanks.

Re: No Hot Water, New Water Heater?

It might be a problem with the cold water in system. The cold water comes into the tank and runs down a plastic tube to the bottom of the tank. The hot water rises and comes out the top of the tank. It this plastic tube brakes or comes off or was not installed or maybe removed by the place were you bought the tank the symptoms you describe may happen.

There was a recall of some of these tubes that were deemed not suitable for this use but I think the recall as expired.

I hope this info helps,


A. Spruce
Re: No Hot Water, New Water Heater?

Look at the lines coming off the tank, one should be marked Hot, the other Cold. Put your hand on the pipes to see if they are indeed as they are marked.

If the hot side is cold and the cold side is hot, then the two lines are reversed, meaning the cold inlet is attached to the hot side.

If the hot side is hot and the cold side is cold, then it is likely a pipe blockage issue between the tank and the point of use.

You say that your house is "very old", which means it probably has steel pipe. Steel and water = corrosion, which means the inside of the pipes are likely clogged with rust. To add insult to injury, when the tank was replaced last year, disturbing the pipes would have knocked rust particulates loose, which have likely completely blocked the pipes. Sounds like it's time for a repipe.

The jury is fairly well split between PEX and copper. Copper is much more expensive, but IMHO, well worth the time and effort to put in. PEX is plastic, with all the known issues that plastic has when it comes to migration of it's chemical elements into the water supply and the health risks involve. You can probably guess which side of the jury I'm on. ;)

Re: No Hot Water, New Water Heater?

Who installed the water heater? If the person who installed it is not qualified, then get a licensed plumber to check it, check the pipes in your house and everything else.

Let us know what you found.

Re: No Hot Water, New Water Heater?

I'm on the other side of Spruce's jury... more or less. PVC, CPVC, and polybutylene plastics do leach chemicals into the water. PEX (cross-linked polyethylene) is many times more stable and the leaching is nearly nil (same material as plastic milk jugs and the lining of paper milk cartons). Copper is good except that it will react with some water to create harmful copper compounds. PEX hasn't been shown to be reactive and the pipe will not burst when frozen. My preference is PEX, though it requires special, expensive tools a homeowner isn't likely to have. With the tools, PEX is easier to work with than copper.

Steel is not good for water pipes, for all the reasons Spruce mentioned. Plus, the difficulty of working with steel often results in a high incidence of bad words.

Do not join copper pipes directly to steel pipes. Use a dielectric union; this fitting has a plastic washer that electrically insulates the two types of metal. When the two metals are in contact in water, one or the other will be eaten away (through a process called galvanic corrosion) depending on whether the water is acidic or alkaline.

Re: No Hot Water, New Water Heater?

My first thoughts are like A. Spruce- a pipe reversal gives very similar symptoms and can easily happen if both hot and cold piping is the same material and not marked or easily identified. Seems to be most common in new apartments plumbed with CPVC and both sides coming from the floor or ceiling together. Probably the WH install crew wasn't the rough-in crew so didn't know which was which. With PEX colors make the determination easy.

Around here, the water pH is usually benign so copper makes a good choice and is preferred by many old-timers, but PEX is rapidly taking over for a number of reasons and as far as I can tell is the way to go these days- cheaper, faster, easier to run, less prone to freeze damage, and no torches to carelessly scorch the drywall (or worse). DIY'ers will do well with just a "Pocket Crimper" on PEX, Pro's will use purpose made crimpers with one tool for each size line. In most remodels I just go with whatever is already there except for galvanized which is always replaced with something better.


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