Type of hydronic system

[Robert Jones]

Can anyone tell by the attached picture what kind of radiant heating system was used, ie; closed etc...?

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[Chad Fabry]

I don't understand the question.

[Robert Jones]

I hate it when the response starts like that, it means I am about to be humbled;) I read where there are basically three types of hydronic systems; closed, indirect and open direct. I just didn't know if it was pssible to tell by the photo what type was installed in this home.

http://www.radiantec.com/systems-sources/systems.php

[hausdok]

Hi Robert,

I think I was the very first person to view your post. I didn't respond because there's really not a whole lot anyone can tell from the picture.

ONE TEAM - ONE FIGHT!!!

Mike

[Chad Fabry]

I hate it when the response starts like that, it means I am about to be humbled;) I read where there are basically three types of hydronic systems; closed, indirect and open direct. I just didn't know if it was pssible to tell by the photo what type was installed in this home.

http://www.radiantec.com/systems-sources/systems.php

Isn't all the tubing in the photo disconnected?

Closed means the heating unit or heat exchanger directly heats the water in the closed heating loop, and the water is always in the system- like a conventional hydronic system using the floors as radiators .

In an indirect system, there is a separate closed or open loop which picks up heat from the source and delivers it to the load via heat exchanger. My system is an indirect system.

And, open loops are filled with potable water @ line pressure- think of them as long hot water plumbing.

So, if all the plumbing originates and terminates at the heat source, it's closed.

If the heat source supplies a heat exchanger at least that loop is indirect- maybe the entire load is indirectly heated.

If the domestic water is directly or indirectly heated and it is also used as the heat exchange medium in the heating system, then at least that loop is an open loop.

[kurt]

I couldn't tell anything from the pic either. My guess is it's an indirect system; that water heater looks like it's got secondary connections.

[Marc]

Isn't all the tubing in the photo disconnected?

Closed means the heating unit or heat exchanger directly heats the water in the closed heating loop, and the water is always in the system- like a conventional hydronic system using the floors as radiators .

In an indirect system, there is a separate closed or open loop which picks up heat from the source and delivers it to the load via heat exchanger. My system is an indirect system.

And, open loops are filled with potable water @ line pressure- think of them as long hot water plumbing.

So, if all the plumbing originates and terminates at the heat source, it's closed.

If the heat source supplies a heat exchanger at least that loop is indirect- maybe the entire load is indirectly heated.

If the domestic water is directly or indirectly heated and it is also used as the heat exchange medium in the heating system, then at least that loop is an open loop.

Chad, I offer an explanation with a different play on words. Pls tell me if I've the correct idea or not. I've never seen a radiant system so I'm in the learning phase.

Open/Closed refers to whether or not the water in the hydronic system is open to the water in the fresh water plumbing system serving the house.

Direct/Indirect refers to whether or not there is a water-to-water heat exchanger between the hot water supply and the radiant loops. Indirect implies the presence of an exchanger.

Marc

[David Meiland]

Not enough info from the photos. One term we use here is primary vs. primary/secondary, the latter being a system where the boiler heats a primary loop which then feeds different water temps as needed to radiators, tubing in floors, etc. Robert, were there rads in the house, tubing in floors, or what?

[kurt]

It's been so long since the Watts seminars, I'm getting fuzzy on terms.

The nice systems here use primary and secondary loops, with the primary being either direct or indirect.

It's like anywhere else; local vernacular can confuse things.

[hausdok]

Hi,

Well, to expound on what I said earlier; the photo doesn't tell us anything because I believe that the system that had been there was removed and the water heater you see in the photo is what's been used to replace the wall-hung unit that was on the far wall. If that unit were still there and the photo was larger, I'd be able to tell whether the water heater was heating the water in the system directly or whether the heating loop was closed and heated by some kind of exchanger external to the water heater. Since all you have is the remnants of the tubing without the water heater, manifolds or controls, it's like looking at a pro-stock racer with the interior and dash stripped out and wondering, without talking to the owner, whether the original car had A/C or not.

ONE TEAM - ONE FIGHT!!!

Mike

[Robert Jones]

Thanks guys. I knew the pic wasn't going to do much justice with regards to my question. The homeowner(also the builder), took the device that attached to the water heater. The hydronic heat is in floor, not radiator type. I went ahead and attached a pic of the water heater.

[Chad Fabry]

Isn't all the tubing in the photo disconnected?

Closed means the heating unit or heat exchanger directly heats the water in the closed heating loop, and the water is always in the system- like a conventional hydronic system using the floors as radiators .

In an indirect system, there is a separate closed or open loop which picks up heat from the source and delivers it to the load via heat exchanger. My system is an indirect system.

And, open loops are filled with potable water @ line pressure- think of them as long hot water plumbing.

So, if all the plumbing originates and terminates at the heat source, it's closed.

If the heat source supplies a heat exchanger at least that loop is indirect- maybe the entire load is indirectly heated.

If the domestic water is directly or indirectly heated and it is also used as the heat exchange medium in the heating system, then at least that loop is an open loop.

Chad, I offer an explanation with a different play on words. Pls tell me if I've the correct idea or not. I've never seen a radiant system so I'm in the learning phase.

Open/Closed refers to whether or not the water in the hydronic system is open to the water in the fresh water plumbing system serving the house.

Direct/Indirect refers to whether or not there is a water-to-water heat exchanger between the hot water supply and the radiant loops. Indirect implies the presence of an exchanger.

Marc

I hate it when other people are more concise than me.

[hausdok]

Hi Rob,

What's the manufacturing date on the water heater? Are you sure he didn't simply strip out a tankless dual-purpose wall-hung water heater along with the circulators and manifold array and then cobble in a new tank-type water heater? I still don't see how that water heater is connected to the floor heat. Are there pictures from another angle?

ONE TEAM - ONE FIGHT!!!

Mike

[Jim Katen]

Originally posted by Chad Fabry

I hate it when other people others are more concise than me I.

[hausdok]

Ah,

Now that you've posted the second coil and I've looked more closely at the first I think I see what's been done. It used to be a system that used a tankless water heater. He removed that tankless water heater and hooked up the system directly to a new tank type water heater (Now I see the minifold array on the left wall).

My guess is that the sytem that had been used had a tankless water heater that utilized a closed loop system with a plate exchanger. When he stripped out the tankless, he took the plate exchanger with him. However, instead of hooking up the water heater to the potable water on one circuit, and the heating loop portion of the system to the in-tank coil on the other circuit, he's plumbed them all off the potable water side of the tank.

Is that a whole lot of disconnected tubing protruding from the floor and walls? If so, that means that those disconnected portions are no longer in use and only part of the in-floor is actually heating the home. Is the floor heat even hooked up?

The way the tank is configured, the temperature of the water leaving that tank is controlled using the tempering valve at the top of the tank. The point of that is one can crank the temperature of the tank way up, in order to have water temps that will allow the floor heating system to actually work, while still maintaining domestic hot water at a safe 120?F or less. If he's hooked the hydronic heating system directly to the potable water side of the tank and isn't controlling the temps of the two systems separately, the only way the floor heat will function properly is by cranking the water temperature way up on the tank and cranking the tempering valve all the way over to the hot side so that temps reaching the hydronic system are where they need to be. That works fine for the floor heat, but he'll end up with scalding hot water at the fixtures and be running the risk of third degree burns. Then, if the hydronic system is hooked up, there's the issue of constant circulation through that system. They aren't supposed to be plumbed so that they constantly circulate because then you run into issues with pipe scour.

That floor system needs to be configured to circulate through those two nipples on the side of the tank and the pipes coming off the top of the tank need to be connected to only the DHW circuit so that DHW temp can be kept at 120 or less by the tempering valve.

Contact Northwest Mechanical and talk to Buzz and send him some photos.

ONE TEAM - ONE FIGHT!!!

Mike

[Chad Fabry]

Originally posted by Chad Fabry

I hate it when other people others are more concise than me I.

You're funny, kind of a dick, but funny.

[Robert Jones]

Thanks Mike,

No there is no heat in the home as the only source was the in floor radiant type. I was just curious as to what was removed(type of system). Those are pex tubes coming out of the floor, the home was a basement type.

[John Kogel]

Thanks Mike,

No there is no heat in the home as the only source was the in floor radiant type. I was just curious as to what was removed(type of system). Those are pex tubes coming out of the floor, the home was a basement type.

It looks like someone pulled a little gas boiler off the wall and sold it. Now why would somebody do that? []

I would say it looks to have been a closed system. My guess is that the tank heater is for domestic HW, still working? and the pex pipes were a separate system. But there are the copper pipes coming down from the ceiling, so who knows?

It can still be a closed system and, what I often see here, anyway, have a line with a check valve and a pressure control off the main supply line. So that could be a makeup water supply line there. And there's that T on the WH, so who knows?