Well I've screwed myself-need a heating design person

[hupte]

The large grey PVC is a drain line from the bathroom heading out. All this is in the basement.

ok i hope its plumbing pvc. not electrical conduit pvc. cause the plumbing pvc glue used with plumbing pvc, or electrical conduit glue is not designed to be used in plumbing. it will likely fail. but if you have rubber boots on both ends and its still holding. hey, more power to ya.

 

[Kevin in Ohio]

ok i hope its plumbing pvc. not electrical conduit pvc. cause the plumbing pvc glue used with plumbing pvc, or electrical conduit glue is not designed to be used in plumbing. it will likely fail. but if you have rubber boots on both ends and its still holding. hey, more power to ya.

Well, It's schedule 80 PVC and it has been in service for over 30 years. Schedule 80 is stronger/thicker than your typical white, schedule 40 stuff. I'm more worried about the cast iron.

 

[brenndatomu]

ok i hope its plumbing pvc. not electrical conduit pvc. cause the plumbing pvc glue used with plumbing pvc, or electrical conduit glue is not designed to be used in plumbing. it will likely fail. but if you have rubber boots on both ends and its still holding. hey, more power to ya.

I have never seen PVC glue broken up into PVC plumbing or PVC electrical categories. ABS, CPVC, PVC, yes, but not PVC vs PVC. Most people that work on the stuff often use the universal cleaners and glues anyways...oh, and those rubber boots..Ferncos, in the right application and installed correctly, are awesome!

 

[hupte]

here is an image of a completely wrong install . this is the kind of thing i was referring to. clearly different than a drain line. this is a pressurized line. I think this install was done by unclemoustache!!! lmho!!!!

 

[kljahnz]

why would you want the hot water to stay on top of the tank? isn't it gonna stay there anyways? heat rises right? Also why would you want to reduce mixing? usually you want the water to flow to avoid the potential of corrosion and mineral deposits, also to keep the water at a more consistent temp.

Stratification.. if your emitters like 140 temps, having your tanks mixed at 130 top to bottem won't do much good. Infloor emitters can go down to , say, 100. But if it's -10 outside and your storage is at 105, you'll be trying to catch up for quite awhile. Hope that helps.

 

[Homelitenut]

Ok I'm going to sound stupid and I probably shouldn't be posting in this thread but we have a very simple owb it's just a fire box with a water jacket with a pump that runs all the time drawing from the top of the water jacket running to a heat exchanger on the intake of our regular central heating and air system then the water just circulates back to the bottom of the water jacket. The blower on the furnace is operated by a separate thermostat and and relay. On the firebox there's a small blower on the door that blows air in the firebox when the water temp gets to 155* and kicks off at 160* so the water temp stays pretty constant. We fill it with wood once in the morning and once in the evening. It's a earth wood stove rancher 360.

 

[Guswhit]

Your schematic looks pretty good. I would try to isolate each piece and lay it out like Kevin stated. take the pieces you have and see if you can lay it outView attachment 406306

The issue I see is the electrical control valves and a good heating guy who has experience installing boilers should be able to help you. Here is a diagram of a 2 tank storage system. This does not use a heat exchanger. I would recommend the heat exchanger. Putting color to your diagram might help you understand the flow, etc. Hope this helps.

In this picture, isn't the thermoplastic valve/pump/mixer essentially doing the same as a plate heat exchanger, but slower? I mean it is taking cold water and mixing it back out of the bottom of the tank to the boiler a little at a time right? I think I read somewhere that they use this method to prevent shocking the boiler(gas boiler though) with too cold water. I have bought a couple books and I'll keep going. Don't have to have it all finished till about November, hope I make it.

 

[Guswhit]

Ok I'm going to sound stupid and I probably shouldn't be posting in this thread but we have a very simple owb it's just a fire box with a water jacket with a pump that runs all the time drawing from the top of the water jacket running to a heat exchanger on the intake of our regular central heating and air system then the water just circulates back to the bottom of the water jacket. The blower on the furnace is operated by a separate thermostat and and relay. On the firebox there's a small blower on the door that blows air in the firebox when the water temp gets to 155* and kicks off at 160* so the water temp stays pretty constant. We fill it with wood once in the morning and once in the evening. It's a earth wood stove rancher 360.

So what is the question or statement you are trying to make?

 

[kljahnz]

@Guswhit
my phone won't let me open your proposed blue print....
can you add it as a pic or something else? I'd sure like to view it.

 

[hupte]

In this picture, isn't the thermoplastic valve/pump/mixer essentially doing the same as a plate heat exchanger, but slower? I mean it is taking cold water and mixing it back out of the bottom of the tank to the boiler a little at a time right? I think I read somewhere that they use this method to prevent shocking the boiler(gas boiler though) with too cold water. I have bought a couple books and I'll keep going. Don't have to have it all finished till about November, hope I make it.

well, not exactly. the plate exchanger is basically to protect your tanks from overheating, it also isolates the systems (boiler system and house system) it also gives you more options for temperature regulation, regulating the tank temps vs the inconsistent boiler temps. among other reasons.
the cold water mixing valve, in your application is basically so you don't over heat your floors, also (fringe benefit) makes it more consistent temp throughout the floor heat. also makes the pipes contract and expand less as the heat turns off and on. this helps maintain the longevity of the system and you dont have to listen to the pex lines creeking as they expand, depending on the application.

in the diagram that outback rider posted the 3 way mixing valve is to prevent the tanks from overheating.

now a 4 way mixing valve is designed to prevent boiler shock AND prevent overheating your floors. based on your diagram, you don't have a 4 way. and you don't need one with your p&m.

 

[hupte]

Stratification.. if your emitters like 140 temps, having your tanks mixed at 130 top to bottem won't do much good. Infloor emitters can go down to , say, 100. But if it's -10 outside and your storage is at 105, you'll be trying to catch up for quite awhile. Hope that helps.

first off i really like your avatar!!! lol.

i understand what your saying, after another look at the op's diagram, it appears that the system is designed exactly as your saying. i would think that would kind of defeat the purpose of 500g of storage. on the one hand the heat would last longer after the owb cools off. but on the other hand the recovery would be shorter. the cooler (relatively speaking) water in the bottom of the tank would act as yet another buffer to keep consistent temps. since when the hottest water starts to cool you still have all the cooler water in the bottom of the tank to rely on. so i can see the point.

 

[Homelitenut]

So what is the question or statement you are trying to make?

I was just stating what we have and use that's all

 

[AIM]

I just have what is likely a dumb question. Isn't the boiler an open air non pressurized system. If so why the expansion tank and pressure relief valve?

 

[Guswhit]

@Guswhit
my phone won't let me open your proposed blue print....
can you add it as a pic or something else? I'd sure like to view it.

 

[Guswhit]

I just have what is likely a dumb question. Isn't the boiler an open air non pressurized system. If so why the expansion tank and pressure relief valve?

I believe that the twin tanks will be pressurized to around 12 psi if what I have read and paid attention to are correct. Just received "Pumping away" book in the mail so still reading up.

 

[hupte]

one thing i forgot to mention is when your building be really carefull not to install the in floor heat too close to any toilets. the floor heat can make the wax ring melt resulting in sewer gasses escaping into the house.

 

[NSMaple1]

I believe that the twin tanks will be pressurized to around 12 psi if what I have read and paid attention to are correct. Just received "Pumping away" book in the mail so still reading up.

Yes, everything to the right of the FPHX is pressurized. You will need a fair sized expansion tank for 1000 gallons.

Re. the boiler, I might consider moving the pump to the return side down low, since it's not pressurized (I don't think?). And, since it is open, I'm not sure how you will make sure the water level stays good so the HX circuit won't airlock, if it is above the boiler like that. Just not sure about the boiler side there, I think the boiler side is open but it's not drawn with an opening if I said that right.

 

[Guswhit]

Yes, everything to the right of the FPHX is pressurized. You will need a fair sized expansion tank for 1000 gallons.

Re. the boiler, I might consider moving the pump to the return side down low, since it's not pressurized (I don't think?). And, since it is open, I'm not sure how you will make sure the water level stays good so the HX circuit won't airlock, if it is above the boiler like that. Just not sure about the boiler side there, I think the boiler side is open but it's not drawn with an opening if I said that right.

Picture/drawing is not showing correct elevations, only placements. The OWB will be in an almost level line to the area where the exchanger will be placed. OWB is marked as to which ports are to be used for inlets and outlets by the manufacturer. Boiler side is open.

one thing i forgot to mention is when your building be really carefull not to install the in floor heat too close to any toilets. the floor heat can make the wax ring melt resulting in sewer gasses escaping into the house.

Definitely will skip the area around the wax ring in the basement floor. I had already heard of some horror stories.

 

[kljahnz]

you show two modine water to air heat exchangers, are they in two seperate buildings? maybe that was already covered and I missed it. How long are those runs?

 

[Guswhit]

you show two modine water to air heat exchangers, are they in two seperate buildings? maybe that was already covered and I missed it. How long are those runs?

One will go to the house furnace, maybe 20' at the most from the placement of the tanks and the other will be in the upper garage area directly above the tanks, again no more than 20', I haven't decided the exact placement of that one yet.