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[CountryBoyJohn]

One other thing I thought of and Mr. Hondaracer hit on it. After you changed your setup how long did you let the water run. If your tank isn't up to temp, open the hot side of a tub and let it run. After a minute, the downstream side of your domestic side should be hot just like Honda says. It will take upwards of 5-10 minutes for your tank to come up to temp as well as the tub water. After it is up to temp, you should have hot water readily available.

[Roger2561]

Read what hondaracer2004 and CountryBoyJohn have to offer.  I had to do the same thing.  I was very disappointed when I installed mine but I talked to one of the guys I work with and he told me to run the hot water in a sink or tub or shower, etc... for about a minute.  You may have to do this a few times.  Every 5 minutes I turned on a faucet and to see how it was doing.  After a few cycles of turning on the water for about a minute and then waiting a few minutes I had and continue to have plenty of hot water.  Don't give up.  You'll get it.  Roger

[kommandokenny]

to run the hot water in a sink or tub or shower, etc... for about a minute.  You may have to do this a few times.  Every 5 minutes I turned on a faucet and to see how it was doing.  After a few cycles of turning on the water for about a minute and then waiting a few minutes I had and continue to have plenty of hot water.  Don't give up.  You'll get it.  Roger

Ya I got that part of it and I even put the electrics on it to boost the water temp up.
I then played around with the facets, opening and closing .
As soon as you turn on a facet the xplate goes cold.
It never did that with the old plumb through the bottom of the tank.

Anyway took a shower just now after priming DW into the exchanger all day.
It was ok ,,,,,had the mixing valve shut and the shower faucet on full hot.
LO PRESSURE, but it was warm enough.
[Not acceptable]
The way I see it, the small 10 plate exchanger just can't keep up.
For this to work, for now, I would have to leave the kitchen facet on a trickle 24/7 to slowly draw water continuously into the plate exchanger.
I don't know about pump speed GPM etc.
Your saying the faster the stove water goes, the better??
I'll post the pump model etc.
Sure heats the house fantastic!!!!

Thanks
kk
 

[cando attitude]

Absolutely agree with Slim.  You have two options:

1.)  Install a small circulation pump on the hot water tank so it pumps the water through the HX

2.)  Change the HX to a true sidearm style, which is built to better facilitate convective heat transfer, i.e. longer/taller design so that it starts to pulls cold water from the bottom and dumps hot water out the top (much like a tall chimney drafts)

Cando

[hondaracer2oo4]

No water pressure? Your hx is plugged. That is why no exchange is happening.

[CountryBoyJohn]

Absolutely! If you are running full hot and don't have pressure, your exchange is clogged!

[slimjim]

I would also agree that the exchanger is plugging up, while you are at it I would change it out with a 20-30 plate and install purge ports and valves on all ports so it can be cleaned without removal next time!

[kommandokenny]

No water pressure? Your hx is plugged. That is why no exchange is happening.

Oh sorry, I had pressure to the shower last night, but with no cold water mixed in, it was poor.[1/2 pressure]
The way it was plumbed before, water came in slowly from the bottom [semi warm] to the exchanger.
The exchanger stayed hot when opening a facet.
Now,, with it coming directly through the exchanger from the well at 40psi the exchanger goes cold when you turn on a facet.
I'm thinking it was originally plumbed through the bottom of the tank to the exchanger to compensate for the poor flow?

The exchanger is not plugged, I did not explain things right.

Like you say, water will take the least restrictive path back to the Owb.
That would be the larger 1 inch return to the OWB and not pressurize the HWT circuit??
Going to post pictures

Thanks keep the ideas coming We're getting close ,,maybe,,??

Cheers

[kommandokenny]

Ok. Probably should've asked this first, but what is your pump setup? We need the model, size, and head loss. You may not have enough flow through your stove side of the exchanger.

Hang in there. We can get this figured out.

Country Boy ,This got me thinking about the flow to the exchanger.
Cold water coming from the well directly into the exchanger at 40 psi.
Hot water from the owb via the "T" JOINT may not be under enough pressure to heat the cold water.
The 3/4 " HWT circuit is an offshute from the main 1 INCH line.

Is the setup sposed to be in series, ie ,1 inch pex going in to the HWT then out,, and  directly to the fan forced furnace and back to the OWB.
A complete circle???




kk

[kommandokenny]

Absolutely agree with Slim.  You have two options:

1.)  Install a small circulation pump on the hot water tank so it pumps the water through the HX

2.)  Change the HX to a true sidearm style, which is built to better facilitate convective heat transfer, i.e. longer/taller design so that it starts to pulls cold water from the bottom and dumps hot water out the top (much like a tall chimney drafts)

Cando

Agee with that.
I think I got cheaped with the installation.
No drain setup on the lines either.
It kinda 1/2 works.
Should of been a complete series circuit with a proper side arm x
 

[kommandokenny]

One other thing my temp setting on the OWB is 160 /170 f
Would cranking it up 10 degrees do much??

I know I mentioned this earlier in one of my posts

[hondaracer2oo4]

Yeap, that is another big problem. Flat plates have a lot of resistance. Water isn't going to flow through it well because of the fact that it needs to make a 90 degree turn then go through a high resistance device. But if you have low flow on the owb side of the hx you should have hot water entering the hx from the owb and cold leaving because of how much heat was exchanged fr the low flow. Your hot water pressure and your cold water pressure in your house should be equal. If they are at all noticeably different then you have a plugged up hx on the domestic side.  It is likely that it is plugged up on the owb side too because it also is not exchanging any heat over to the domestic. I would remove it from the system and flush it per flat plate exchanger flushing procedures.

[kommandokenny]

It's not plugged, it's new.
The heat is exchanged, but poor recovery time .
ie can't keep up. Be it size, or flow from OWB
I have seen how this is supposed to be plumbed with a side arm exchanger in a circle.
I think it has to be started over and a side arm xcanger incorporated in a loop???

KK

[kommandokenny]

Yeap, that is another big problem. Flat plates have a lot of resistance. Water isn't going to flow through it well because of the fact that it needs to make a 90 degree turn then go through a high resistance device. But if you have low flow on the owb side of the hx you should have hot water entering the hx from the owb and cold leaving because of how much heat was exchanged fr the low flow. Your hot water pressure and your cold water pressure in your house should be equal. If they are at all noticeably different then you have a plugged up hx on the domestic side.  It is likely that it is plugged up on the owb side too because it also is not exchanging any heat over to the domestic. I would remove it from the system and flush it per flat plate exchanger flushing procedures.

It's still not plugged.

The OWB Hot into exchanger is  hotter than return = heat loss,/ transfer
The Domestic in,,, turns the exchanger from hot to cold = heat transfer.
I could be missing something of course

kk

[hondaracer2oo4]

Alright let me explain. There are a multiple methods and piping set ups to heat your domestic hot water. The two methods are a flat plate heat exchanger or a side arm heat exchanger. Lets talk about the Flat plate first.

Flat plate. 4 Ports on the flat plate. 1 in from boiler and 1 out to boiler. 1 in from domestic and 1 out to domestic.

Flat plate exchange. Water enters flat plate from boiler, travels back and forth between plates with domestic water on the other side of the plate. Number of plates = number of passes through the exchanger. Water on the domestic side passes through the plates in the opposite direction exchanging the heat into the domestic water. Obviously the more plates in the exchanger the longer the boiler water is able to exchange heat thus more btus can be exchanged to the domestic side. If you were to turn on the water at a faucet with a 10 plate you should be able to bring 50 degree well water up to atleast 100 degrees by the time it gets through to the other side of the exchanger. Any more water flowing then this would likely be over the capacity of the exchanger leading to cooler water leaving the exchanger on the domestic side.

Flat plate plumbing options. You can either pre heat your water before it enters the tank(what you have plumbed now) or you can heat it after it leaves the tank like an On Demand water heater.

Pre Heating water- You will heat domestic water as it enters your tank when a faucet or shower etc calls for water in the home. The water that has been sitting in the tank will hopefully still be above your 100 degrees that you want. This all depends on how much you call for water in the house. Many people utilize this plumbing method and it works just fine.
Post heating your water- You put the exchanger after your water leaves the water heater. This is a 'on demand' style plumbing set up. You would likely need a 30 plate exchanger to ensure that whenever a call for heat occurs that you will be able to meet the btu demands.

Side arm- Water is piped in on the domestic side from the bottom drain, through the side arm and then back into the tank through the over pressurization bung. Water on the boiler side travels through the side arm creating a 'thermosiphon' where the cold water at the bottom of the tank naturally wants to rise towards the warm water in the exchanger creating a natural flow of water exchanging cooler water at the bottom of the tank. S
Sidearms tank a while to recover water temp inside the water heater since there is no flow from the domestic causing the water exchange.

So in conclusion you have your domestic side piped correctly for a flat plate pre heater. This set up works perfect once you fill your water heater full of hot water and replenish if with hot water everytime your house calls for water. If you have any significant drop in water pressure on your hot water domestic side this means that you likely have a plugged up exchanger. I have no idea how hard your water is at your home, it could plug up the small passages in your flat plate in months if the water is hard enough. If you flow a faucet in your home and go and feel the the domestic water leaving the hx headed to the bottom of the water tank and it is only luke warm that means that you are not exchanging the heat. This could be because your are plugged up or you are flowing water to fast through the hx(heat exchanger does not have enough plates)  on the domestic side.

Lastly I don't think you should have the T plumbed in the way you do for the hx from the OWB. You should be feeding the flat plate inline with your indoor furnace water to air hx. You also shouldn't reduce the size down to 3/4, this just creates even more friction loss in the system.