Coalpail.com Forum

What do you think of the last post on how I have my system setup?

McGiever wrote:Take a look at these three plumbing scenarios, disregard some requirements that would not apply to your situation.

DHW Plumbing.JPG

Option 1 looks to be adaptable to what you have shown.

I have been using Option 2 for some time now.

I had a third hole on top of tank w/ T/P valve, just removed T/P to add a Tee, and then replaced T/P valve into Tee and used other side of Tee to feed Hot out to house.

Bought a second dip tube and inserted it into factory Hot out to house and fed it from circulation pump...other side of circulation pump is simply Tee'd into normal Cold supply line.

Option 2 wouldn't quite work right if your T/P is coming out anywhere but on the top of the tank though.

Don't leave out the heat traps.

Back in my first post I asked "Why the extra tank?" If the reason is for more storage capacity then you might do things differently than if the answer is to save money.

Sting saw the one thing that my brain skipped.... the pump is running. I saw that as "recovery will take a long time". Sting saw it more properly as "it removes stratification'. Also, my brain missed the thought that the pump is running while you use hot water. That negates stratification and you just won't be happy. Most of the time you'll have luke warm water because in the time it takes to use 3 gallons of hot water, 3 gallons of cold has been mixed with all the water. In a normal circumstance, that 3 gallons of cold sits at the bottom of the tank, leaving the rest of the gallons of hot ready to use.

That's the problem with free advice....sometimes it's worth what you paid for it.

I might be inclined to use only the GE and see if it does the job. As I sit here now I'm starting to realize that GE probably spent a zillion dollars on design and asking it to maintain an extra 80 gallons might be out of it's reach.

So... Now that Sting has jolted my brain in the right direction. Let's start over. Why the extra tank?

The extra tank is for increased capacity. I'm not sure 50 gallons can handle what I want to throw at it. 3 showers back to back. My daughter takes a 15 minute shower then the wife showers right after her for 10-12 minutes and then I shower about 40 minutes after my wife. What if I leave the design as is. Cold water from the GE tank goes into the cold water inlet of the storage tank and the the hot water for the storage tank is feed (pumped) into the top of the GE tank. What if I leave it like this and put the circulator on a timer so it stops pumping during our showering times. Since there is a dip tube in the storage tank I don't see why this setup wouldn't work and help to increase capacity??

traderfjp wrote:What if I leave the design as is

You can try it. I guess that's the only way to know if it'll do what you want.

You should do what I did when my daughters came the age they took showers on their own. I taught them that 5 minutes is plenty of time to shower. When they went to take a shower I'd go to the cellar & stand by the water heater. After 4 1/2 or 5 minutes I'd slowly turn the hot water off. In the shower they would think the tank was running out of hot water & they'd hurry up & finish. It only took a few times to "teach them". & ya know...they never questioned how it recovered so quickly if the second daughter took a shower directly after the first. Heh heh heh.

Women have a love afair with hot water. I'm not sure why but they do. If I even thought about what you did I would be toast! Eventually I will put a coil in my stove and steal some heat that way too. I could have bought an 80 gallon HWH that uses a heat pump but the costs were double and it didn't have an excellent 11 year warranty like I have now through Lowes. I think the new design with timer will work.

Would this design work better?

Too late for me to give any advice, I wouldn't buy one to begin with, the area we live in ( North East ) is by no mean a good place to use heat pump to heat water. Nine months out of the year ( especially this year ) we are trying to keep ourselves warm, there hasn't been all that hot weather for the heat pump to steal heat from and supply hot water.

On top of that , it's an insult to this forum, I just came back from watching a coal stoker converted into a hot water maker, at the expense of one hopper per week, do the numbers, you'll realize even while confused by my beer, that a ton of coal should provide hot water for a full year. that's very hard to beat.

But if you like falling into the politics of green, rebates, and all others, by all mean spend that extra money you have so it could rejuvenate the economy by having it circulating around, and hopefully we'll have Reaganomic effects. ( trickle down )

traderfjp wrote: I could have bought an 80 gallon HWH that uses a heat pump but the costs were double and it didn't have an excellent 11 year warranty like I have now through Lowes. I think the new design with timer will work.

Will the warranty do any good if your setup doesn't work?

traderfjp wrote:Would this design work better?

I will go back and lay by my dish after this final attempt so

Let my comment/answer not be misconstrued again

---> NO <---

you still do not grasp the concept of stratification disruption and how it will kill everything you seek to achieve

maybe a little primer from solar systems will help you

http://researchrepository.napier.ac.uk/2507/

I know you said you want more storage, but I really wonder if the heat pump has the recovery capacity to make use of the extra storage tank.

Why not skip the circulator pump entirely? Run cold water from the street or your well into the cold water inlet of your GE tank, and set the GE tank to run in heat-pump-only mode.
Outlet from the GE tank will go into the cold water inlet of your second tank, and the second tank will be conventionally heated (electric or oil or whatever). Outlet of the second tank goes to your faucets.

That way the heat pump tempers the water going into the second tank, raising it from 50 degrees to whatever it is capable of. The second tank assures you have a "normal" quantity of hot water, but whatever energy the heat pump provides will reduce the energy needed by the second tank.

Of course, if the second tank is electric then as Freddy says, What's the point of the second tank, just use the GE in its hybrid mode.

Or maybe put TWO GE systems in series as above, the first in heat-pump-only mode and the second in hybrid mode; or both in heat-pump-only if that provides enough hot water. We have all kinds of ways for you to spend more money!

ok

Ill lift my head out of the dog dish one more time

Never install dual Domestic hot water heaters in Series

Always and only Parallel

REMEMBER:

tanks like this need temperature--- wait for it -- Stratification!

Series install defeats that.

Kind Regards
Sting

Sting wrote:Never install dual Domestic hot water heaters in Series ... Always and only Parallel ... Stratification!

Stratification! Yes, I would agree, IF we were talking about identical water heaters, especially two electric heaters where the top element heats the water at the top, then goes off and the bottom element heats the water at the bottom. However, the GE in heat-pump-only mode apparently ignores stratification because the coils encircle the bottom 2/3 of the tank. My suggestion to hook them up in series was solely so the heat pump would temper the ground water, so it enters the second (standard) tank at perhaps 80 or 100 degrees instead of 50 degrees. Stratification would still work normally in the second tank. And again, it only makes sense if the second tank gets its heat from something other than electric. A drawback of two tanks is, more standby loss due to more surface area.

dual dhw tank rules still apply to dissimilar appliances

Although the installation of two different tanks usually sucks - regardless of the contraption install

traderfjp wrote:The extra tank is for increased capacity. I'm not sure 50 gallons can handle what I want to throw at it. 3 showers back to back. My daughter takes a 15 minute shower then the wife showers right after her for 10-12 minutes and then I shower about 40 minutes after my wife. What if I leave the design as is. Cold water from the GE tank goes into the cold water inlet of the storage tank and the the hot water for the storage tank is feed (pumped) into the top of the GE tank. What if I leave it like this and put the circulator on a timer so it stops pumping during our showering times. Since there is a dip tube in the storage tank I don't see why this setup wouldn't work and help to increase capacity??

You are on the right track here. I would pipe the storage tank in series with the hp water heater, with the storage tank recieving the cold water first. I would then put a circulator off of a tee on the hot water outlet and pipe it to the cold water inlet of the storage tank. There would be a check valve in the line to prevent bypass and a timer that would allow the pump to only run when the family was not using hot water - at night. This is a charging cycle and should not shut off until close to shower time in the morning.

Stratification is what permits the water to be used. You will be able to get 60 to 80 percent of your storage capacity as hot water before the cold water dilutes it to far below a usable temperature. That means 48 to 64 gallons of hot water.

The bad news is if your shower is a water saving device of 2.5 gpm and your family takes 27 minutes of shower, that is 67.5 gallons of hot water. You will be starting your recovery cycle from the bottom. You will get only the hot water that is recovered in the 40 minutes before you take your shower. If you shower head is old style and uses more than 2.5 gpm, your efforts are in vain.

Heating water above 120 deg. F. will increase your effective storage but will decrease efficiency. You will need a mixing valve on the outlet of the water heater also.

Your best be here is to encourage shorter showers or pay the energy bill and install additional heating capacity.

My shower heads are 1.6 gph so that helps to conserve water. I'm not sure why this wouldn't work if I turned the pump off before showering or maybe a rheostat on the pump so the hot water from the storage tank pumps into the GE tank at about the same rate as the water is being consumed. The hot water in the storage tank shoudl push its way into the GE tank at the top while the cold water stays at t he bottom of both tanks. I understand that a powerful pump will stir tings up and dilute the hot water with cold water but if the pump is off or less powerful??