Announcement Announcement Module
Collapse
No announcement yet.
Hot water recurculating system Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts

  • Hot water recurculating system

    I am having problems with my gas hot water system. It has a re-circulating system on it. The problem I am having is that if the hot water heater sits for a long period of time without being used the water comes out only warm. If it is used regularly it stays hot. It has only caused a problem in the morning when the first shower is taken. Any suggestions on what might be causing it? The tank is only 4 years old. Since we have only been living in the house for about 2 years I can only assume that the re-circulating system attached to the tank is as old as the house, 12 years. None of the plumbers I have contacted locally can tell me what is wrong, only that I need to replace the tank. I don't want to replace the tank if it is not the problem. Any info would be helpful.

  • #2
    I had a similar problem on an older gas tank (8 years) and it was the dip tube. On the cold water side there is a tube that transports the incoming cold water down to the bottom of the tank where it can be heated and not mix as readily with the existing hot water at the top of the tank. My tube was badly coroded and allowed the cold water to enter at the top of the tank

    Comment


    • #3
      Originally posted by Cris:
      I am having problems with my gas hot water system. It has a re-circulating system on it. The problem I am having is that if the hot water heater sits for a long period of time without being used the water comes out only warm. If it is used regularly it stays hot. It has only caused a problem in the morning when the first shower is taken. Any suggestions on what might be causing it? The tank is only 4 years old. Since we have only been living in the house for about 2 years I can only assume that the re-circulating system attached to the tank is as old as the house, 12 years. None of the plumbers I have contacted locally can tell me what is wrong, only that I need to replace the tank. I don't want to replace the tank if it is not the problem. Any info would be helpful.
      I would say you may have one of two problems:

      1) You're water heater is not producing hot enough water. Check the tempreture coming out with a thermometer at the drain. If this is the case it may simply be that your temp. setting is wrong. Adjust it higher. It may also be that your water heater has problems, at which case I would call a competant service plumber (which I am not). He may be able to perform warrenty work as necessary.

      2) You have circulation problems. Your pump may not be functioning, your aqua-stat (the sensor that tells the pumb to circulate) may be bad, or you may have an electric problem between the aqua-stat and the controls.

      If you don't have a clue, I would suggest a competant plumber who is familiar with these systems.

      the dog
      the dog

      Comment


      • #4
        cris,

        When you say you have a recirculating system do you mean you have a circulation pump that keeps hot water circulating through your lines at all times? Thats what a circulating system does. Its common in apartment buildings, hotels, very large custom homes ect ect.. A circulation system in an average home is very uncommon but not unheard of.

        Does the water eventually get hot and stay hot without temperature fluctuations when you leave it run for a while? If so its probably not the dip tube.

        If you have a circulation system, first check to be sure the pump is working. If it is working be sure all the valves to it are on. If the pump is not working look to see if it has a switch in the wire leading to it or if it is just plugged into an outlet. Check to be sure the switch is on or that the pump is plugged in. If you are good so far we need to be sure there is power to the switch or the plug. Check your breaker box for a thrown breaker. If there is not a thrown breaker you will need to use a voltage tester at this point. Please reply how you are doing before we go farther.

        Note: You may have a thermostadt control attached to the return line which turns the pump on and off when it detects that the return water is hot. To determine if your thermostadt is working there are two things you can do. One requires a voltage tester, the other simply by passing the thermostadt control to see if your pump turns on.

        Also let us know if your circulation system actually has a pump. If not i just wasted twenty minutes of my life typing the above paragraphs . Some older construction practices used a gravity circulation system that simply relied on the gradual cooling of the hot water in the lines upstairs to draw fresh hot water up out of the tank in the basement. It was a crude but somewhat effective system.
        Work hard, Play hard, Sleep easy.

        Comment


        • #5
          Cris,

          I think everyone already covered everything but I wanted to mention, you need to be using a fast acting thermometer when you are testing the temperature.

          The back of your hand is great for a guess but if you want to know what your system is doing you need to know what your system is doing.

          If your water is warm at first and then gets hot after it's run for a minute it is likely a bad circulating pump or a poorly designed circulating system. A poorly designed circulating system is one that has long uncirculated branches.

          Mark
          "Somewhere a Village is Missing Twelve Idiots!" - Casey Anthony

          I never lost a cent on the jobs I didn't get!

          Comment


          • #6
            CRIS, JUST TO MAKE IT CLEAR TO EVERYONE, DOES THE HOUSE HAVE WHEELS, OR AN OUTBOARD?
            THE REGULARS WILL UNDERSTAND.
            I LIKE TO PUT SINGLE FAMILY HOMES ON A TIMER AND NOT AN AQUASTAT. LIKE TO SHUT IF OFF AT NIGHT AND SOMETIMES DURING THE DAY WHEN EVERYONE IS OUT. ALSO CHECK FOR A STUCK, FROZEN CHECK VALVE. YOU CAN FEEL THE RETURN LINE ON BOTH SIDES OF THE PUMP FOR WARMTH. ALSO MOST PUMPS WILL HUM WHEN RUNNING. IF IT'S A GRUNDFOS, VERY POPULAR, THERE IS A SILVER COLOR SCREW THE SIZE OF A QUARTER ON THE REAR END YOU CAN REMOVE TO SEE IF THE SHAFT IS ACTUALLY SPINNING. ON A BELL AND GOSSET, ANOTHER COMMON PUMP, THE MOTOR IS CONNECTED TO THE PUMP VIA A SPRING COUPLER. IF THIS PUMP IS SHOT. TOSS IT AND GO WITH THE GRUNDFOS. MUCH LESS EXPENSIVE AND PRETTY MUCH TROUBLE FREE. MAKE SURE WITH ANY PUMP, YOU SHUT THEM OFF WHEN THE WATER IS OFF TO THE HOUSE FOR REPAIRS. ALSO A TIMER IS VERY IMPORTANT FOR THE LONGEVITY OF YOUR PLUMBING SYSTEM. COPPER WILL WEAR OUT IF NOT PROPERLY REAMED, SIZED, INSTALLED AND PROPER PUMP SELECTION. PIN HOLES WILL DEVELOP AND WILL BE A NEVER ENDING BATTLE.
            HOPE THIS SHED A LITTLE LIGHT ON SOME OTHER ISSUES.
            RICK.

            Comment


            • #7
              Thanks for all the information. The system I have is a pump, not sure what name brand. The water is hot on both sides of the pump. Right now we have it set to the "on" position, not using the timer. The pump runs for a short time then shuts off until the water temp falls below a set temp and then kicks on again. Even after the water heater sits and the water cools down, when you turn on the water it is warm, so I am sure the pump is working properly. Even if I let the water run for a long time it does not get hot. The temp stays the same, warm. We have managed to live with the problem by setting the dish washer on delay and running it in the middle of the night. Another way is to get up earlier and turn on the hot water long enough for the heater to kick on and heat the tank again. This takes a while and I hate getting up earlier than I have too. The problem has been livable but a pain in the ***. If it is the dip tube does the hole tank need to be replaced? Another question I have, is it necessary to drain a hot water tank every 3 months to remove the silt? The man we bought the house from said he was told to do that when the tank was installed. I've never done it in any other house we have lived in. We are hooked up to city water so it is not extremely hard water.
              Cris

              Comment


              • #8
                The sediment that builds up in the bottom of the tank acts like insulation between the burner and the water so the more sediment you have the less heat transfer you have.

                The fact that you can get hot water is an indication that the sediment is not your problem. You may have a bad dip tub which can be replaced without removing the tank depending on the repair tube you us.

                You may have a bad thermostat on your water heater. You should not have warm water in your tank from the water sitting over night. As the water in your tank cools the thermostat should turn the burner back on and maintain whatever temp is set..

                Mark
                "Somewhere a Village is Missing Twelve Idiots!" - Casey Anthony

                I never lost a cent on the jobs I didn't get!

                Comment


                • #9
                  YOU MIGHT HAVE A NEWER PUMP WITH A BUILT IN TIMER AND THERMOSTAT.IS THE PUMP RED IN COLOR? IS THE TIMER PART OF THE PUMP ASSY?
                  1 TRICK ABOUT TESTING FOR A BAD DIP TUBE IS TYPICALLY THE WATER WILL BE HOT TO START AND COOL OFF QUICK. WITH A PUMP RUNNING IT SHOULD BE HOT FOR A LONGER TIME ASSUMING THAT THE PUMP IS CONNECTED TO THE BOTTOM AT THE HOSE BIBB DRAIN. A SIMPLE TEST IS TO CHECK THE WATER TEMP. WITH A GOOD THERMOMETER AT THE BOTTOM DRAIN AND THEN AT THE OUTLET OF A 2 HANDLE FAUCET, ONLY ON THE HOT SIDE. MAKE SURE THAT THE HEATER HAS COME UP TO TEMPERATURE FIRST. YOUR READINGS SHOLUD BE VERY CLOSE. IF THE READING ON THE SINK FAUCET IS LOW THEN THE DIP TUBE IS PROBABLY BAD. GENERALLY A DIP TUBE WILL DISINGRATE AND LEAVE WHITE CHAULKY DEPOSITS IN YOUR FAUCET AEREATORS. THIS WAS A COUNTRYWIDE ISSUE IN THE MID 90'S. THE CLASS ACTION LAWSUIT HAS RUN OUT OF MONEY AND I DOUBT THA TOO MANY OF THOSE HEATERS ARE STILL IN OPERATION. IF NONE OF THESE SIGNS LEAD TO A DIP TUBE ISSUE, THEN A MISCALIBRATED THERMOSTAT IS MOST LIKLEY THE CAUSE. I'VE INSTALLED MANY NEW HEATERS WHERE THE THERMOSTAT IS AT FAULT. MOST THERMOSTATS ON RESIDENTIAL HEATERS ARE CALIBRATED TO 10 DEGREES PER NOTCH. WITH A MAX. TEMP OF 160. THE HEAVY NOTCH IS TYPICALLY 125. FACTORY CONSERVATION IS AT 120. YOU CAN TEST TO SEE IF THIS IS TRUE. ALSO THE THERMOSTAT HAS A PRESET ZONE WITHIN THE RANGE OF TEMPERATURE. HE HEATER WILL COME UP TO TEMP, BUT WON'T RESTART UNTIL 5 DEGREES HAS DROPPED.
                  HOPE THIS HAS HELPED AND NOT CONFUSED YOU.
                  RICK.

                  Comment


                  • #10
                    Cris,

                    Your post seems to indicate that your water is hot, but cools after running other fixtures. It sounds like you may be exceeding the flow rate and heating ability of your heater.
                    If this is the case, you may consider (and I would highly advise a competent plumber's advice before you invest money) the following:

                    1) If your water demand is too low, a larger water service, if not a repipe.

                    2) A larger heater.

                    3) Checking out the installation of your hot water piping. If it is not installed correctly, you will not have an efficient system.

                    Please, for your own sake, get the opinion of a plumber before you waste money.
                    the dog

                    Comment


                    • #11
                      Cris,

                      One thing for certain, the problems you are having are not going to be solved by replacing a tank. A tank is a tank is a tank. The controls and accessories contain your problem.

                      When you said the water pipe was hot on both sides of the pump did you just check right at the pump or did you feel farther back away from the pump on the return side? Do you have any flow regulators or baffles in the return line or lines?

                      After re-reading your post and then your informative reply I agree with Rick that the heaters thermostadt is a likely culprit.

                      Plumdog has a point about using a plumber familiar with your system. Check on your tank and there might be a sticker with the name and number of the company that installed your tank or ciculation system. If possible ask the general contractor who built the home for the name of the Plumbing subcontractor he used when the home was built. They should be able to solve your problem if you haven't ironed it out by now..
                      Work hard, Play hard, Sleep easy.

                      Comment


                      • #12
                        Thanks for the quick responses and information. Luckily the homeowners who owned our house before us kept meticulous records so tracking down the original installer of the system is possible. That will probably be the best person to contact. The 2 plumbers I had come out could not tell me why I needed to replace the tank just that I needed to. That was not an acceptable answer when the problem may not have been in the tank. I appriciate all the help. I'll keep y'all posted on what we find out.

                        Comment

                        Working...
                        X