Is hot water heater hooked up properly?
WE just had installed a Carrier GT-PX geothermal unit and had it hooked up to our hot water heater (HWH). Just found out, that this is the first unit our contractor has installed in a residence versus his commerical installations. Found problems with his installation and are questioning whether the HWH is hooked up properly. For starters, the contrator did not turn on the hot water generator system until we questioned him as he didn't know the unit came with it turned off. My husband just got his hands on the manual and found the contrator had hooked up the lines backwards from the geothermal unit to our HWH! The contrator came out and routed them properly. So my question is, how can we tell if the unit is acutally heating up our water in the HWH? My husband is an electrician and can access the unit. So what are the signs that will tell us that the geothermal unit is actually heating our water in the HWH which sits just beside the unit. Thanks for any help you can give me.
turn your water heater off,,see if you still get hot water after a day or so
How many water heaters
do you have? It sounds as if you only have one.
Having just one tank is not a effective method of using the desuperheater. The tanks elements and the desuperheater are competing to make hot water. You need two electric water heaters piped as shown in the drawing. As shown, the first tank becomes a "buffer" tank for the desuperheater. Whenever the Geo is running the desuperheater can produce hot water for you. All day, or night, the buffer tank is being recharged by the desuperheater.
Think of it this way...After your family takes their morning showers and leaves for the day, the electric elements are trying to heat the tank up. If the Geo kicks in it is also trying to heat the tank up. In effect they are fighting one another. With twin tanks, the buffer's water temp gets drawn down as it feeds the main tank. The elements energize in the main tank and the cooler buffer sits there until the stat calls for heating or cooling from the Geo.
the installation manual will show you the installation of a single water heater with a desuperheater installation.
how to tell if it is working? with the unit running, take the temp of the water line going into the carrier unit and the temp of the water leaving. if it is running, you will have a temp rise.
also, your electrician hubby can get his clamp on amp meter out and see if the desuperheater is pulling any amps.
the desuperheater will only run if the compressor is a) running and b) has a hot enough discharge refrigerant line.
we have found that in early summer when the loop field is cold, the desuperheater will not generate hot water b/c the compressor's discharge line is not hot enough.
i would not say that the water heater and the desuperheater are "fighting each other." your water heater produces a minimum water temp and your desuperheater will take that water temp and increase it as much as it can. that said, a 2 tank system is much better since your first tank doesn't have a set minimum water temp to deal with - it will do all the work.
A single tank system with a tankless heater as a booster would be even better than a two tank system. I would love to do this but I am single and cannot justify the cost. My system only warms my water in the summer but in the winter, holy crap. I usually have my water heater off for two or three months. I recently installed a remote control for my water heater to maximumize the off time.
You never said if you water heater is gas or electric.
Manuals are a wonderful thing provided they are read. Here is a way to tell if you are getting hot water.
The unit must be running with the DSH pump on.
Carefully (high voltage here) disconnect the pump (should be a fuse)
With unit still running put your hand on the DSH water OUT line.
Wait about 1 - 2 minutes and reconnect the pump.
You should be able to feel the temperature difference.
If there is a switch for the DSH I suggest you use that instead.
Again manuals are a wonderful thing.
If sized properly a single tank is just fine. You simply disconnect the lower element and leave the upper one attached. The upper element will only fire when you are about to run out of heat generated by the desuper heater. This is how open loop domestic hot water solar systems are done.
Originally Posted by Bergy
One quick way of seeing if your desuperheater is working is gripping the pipe where the water goes into the geo and then gripping the pipe where the water comes out. The out should be warmer than the in by a few degrees if the HWG is working.