Crazy Idea for the Radian Heat !

Walter_3

Hey guys. I have a radian heat Idea. I want to ask all of you experts what you think about the following.
I'm going to build a one story building with basement in Canada. Heat Loss Calculation shows for the basement around 40,000 BTU. 5 loops 250' each, 1/2 pex. The first floor around 45,000 BTU with 3 zones, each one is two loops 250' each. I'll use a regular gas boiler and indirect water heater. I have an idea ! What if I will use the same heat exchanger to heat domestic water and radian heating? I'm going to try to connect the heating line into the heat exchanger's line between the boiler and water heater. Is this going to work? I understand that I have to keep the water in the water heater around 160F to prevent the condensations in the boiler return. After the boiler heats the water heater and pomp and the solenoid valve shuts down, the heating can use the same heat exchanger from the water heater using the water heater like a buffer. Now I have a couple of stupid questions.



1. Is the heat exchanger powerful enough for use in such system? (total load 85,000 BTU)
2. If the boiler begins working, the temperature before mixing valves will quickly increase up to 185F. Will the mixing valves hold selected (say 110F) temperature for the radiant heat without a huge jump in temperature?

3. For the basement I'll use one zone with one pump. 1st floor will have 3 zones controlled trough the zone valves loaded onto one pump. If two zone valves will be deactivated (turned off by the thermostats), and one zone will be left to work how will it effect the pump? Is the flow into this zone increase badly for the pump? What might happen? Noise? Overloaded pump?

This system is good for the following reasons (if it works)
We are saving.

1. avoid using additional heat exchanger.
2. avoid using additional pump for this heat exchanger. All such system (four zones and water heater) only 3 pumps will be used.
3. Because boiler is controlled by the integrated thermostat inside the water heater, we don't' need any additional controllers or relays or thermostats.
4. Domestic water will also be separated from the heating system.5. We save over 1000 bucks.

Please use as much constructive criticism to help me as possible. THANKS!

HAPPY NEW YEAR!!!

<img border="0" src="http://www27.brinkster.com/benchcrew/walter/boiler.JPG" width="576" height="432">

Walter_3

Crazy Idea for the Radian Heat !

Hey guys. I have a radian heat Idea. I want to ask all of you experts what you think about the following.
I'm going to build a one story building with basement in Canada. Heat Loss Calculation shows for the basement around 40,000 BTU. 5 loops 250' each, 1/2 pex. The first floor around 45,000 BTU with 3 zones, each one is two loops 250' each. I'll use a regular gas boiler and indirect water heater. I have an idea ! What if I will use the same heat exchanger to heat domestic water and radian heating? I'm going to try to connect the heating line into the heat exchanger's line between the boiler and water heater. Is this going to work? I understand that I have to keep the water in the water heater around 160F to prevent the condensations in the boiler return. After the boiler heats the water heater and pomp and the solenoid valve shuts down, the heating can use the same heat exchanger from the water heater using the water heater like a buffer. Now I have a couple of stupid questions.



1. Is the heat exchanger powerful enough for use in such system? (total load 85,000 BTU)
2. If the boiler begins working, the temperature before mixing valves will quickly increase up to 185F. Will the mixing valves hold selected (say 110F) temperature for the radiant heat without a huge jump in temperature?

3. For the basement I'll use one zone with one pump. 1st floor will have 3 zones controlled trough the zone valves loaded onto one pump. If two zone valves will be deactivated (turned off by the thermostats), and one zone will be left to work how will it effect the pump? Is the flow into this zone increase badly for the pump? What might happen? Noise? Overloaded pump?

This system is good for the following reasons (if it works)
We are saving.

1. avoid using additional heat exchanger.
2. avoid using additional pump for this heat exchanger. All such system (four zones and water heater) only 3 pumps will be used.
3. Because boiler is controlled by the integrated thermostat inside the water heater, we don't' need any additional controllers or relays or thermostats.
4. Domestic water will also be separated from the heating system.5. We save over 1000 bucks.

Please use as much constructive criticism to help me as possible. THANKS!

HAPPY NEW YEAR!!!

Walter_3

Crazy Idea for the Radian Heat !

Hey guys. I have a radian heat Idea. I want to ask all of you experts what you think about the following.
I'm going to build a one story building with basement in Canada. Heat Loss Calculation shows for the basement around 40,000 BTU. 5 loops 250' each, 1/2 pex. The first floor around 45,000 BTU with 3 zones, each one is two loops 250' each. I'll use a regular gas boiler and indirect water heater. I have an idea ! What if I will use the same heat exchanger to heat domestic water and radian heating? I'm going to try to connect the heating line into the heat exchanger's line between the boiler and water heater. Is this going to work? I understand that I have to keep the water in the water heater around 160F to prevent the condensations in the boiler return. After the boiler heats the water heater and pomp and the solenoid valve shuts down, the heating can use the same heat exchanger from the water heater using the water heater like a buffer. Now I have a couple of stupid questions.



1. Is the heat exchanger powerful enough for use in such system? (total load 85,000 BTU)
2. If the boiler begins working, the temperature before mixing valves will quickly increase up to 185F. Will the mixing valves hold selected (say 110F) temperature for the radiant heat without a huge jump in temperature?

3. For the basement I'll use one zone with one pump. 1st floor will have 3 zones controlled trough the zone valves loaded onto one pump. If two zone valves will be deactivated (turned off by the thermostats), and one zone will be left to work how will it effect the pump? Is the flow into this zone increase badly for the pump? What might happen? Noise? Overloaded pump?

This system is good for the following reasons (if it works)
We are saving.

1. avoid using additional heat exchanger.
2. avoid using additional pump for this heat exchanger. All such system (four zones and water heater) only 3 pumps will be used.
3. Because boiler is controlled by the integrated thermostat inside the water heater, we don't' need any additional controllers or relays or thermostats.
4. Domestic water will also be separated from the heating system.5. We save over 1000 bucks.

Please use as much constructive criticism to help me as possible. THANKS!

HAPPY NEW YEAR!!!

Canuck

Is the system design/heat loss done correctly?

As I see it - you don't have enough tubing down to begin with. 40 MBH basement on 1250' of 1/2" pex = 32 BtuH/sq ft. 45 MBH main floor on 1500' of 1/2" pex = 30 BtuH/sq ft. Perhaps I'm missing something, but I would think that you're 'delta T' is too great in this scenario.
You mention about a second heat exchanger - why? The only one required is in the DHW tank.
Your manifold piping arrangement could work - (not my preference however), but you need to rethink your boiler to DHW tank configuration. Why not make it easy on yourself and go with a primary/secondary piping configuration?

hr

Consider this approch

It would be better to use a reverse indirect where the tank capacity acts as your buffer. Works better than the indirect coil, I feel.

In this example the indirect is the primary loop. Input from the boiler as a secondary, and the radiant, and other loads are considered secondary loops. It's generally better to store BTU's in a nicely insulated tank, as opposed to a boiler with minimal insulation ans possibly a flue through the roof

Or a seperate insulated tank as a buffer, maybe a 40 or 50 gallon electric water heater.

Paste this link to your browser to open.

http://www.pmmag.com/CDA/ArticleInformation/features/BNP__Features__Item/0,2379,78589,00.html

hot rod

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leo g_66

in my opinion

no! i think that the stacking effect within the tank would likely produce little amounts of heat for your idea. also, what happens when you run your heat, reduce the temp of the HWT, then your teenage daughter wants a shower??? LOL!!! WATCH-OUT!!!
like most things, i would venture that this idea has occured to numerous people, and has been rejected, because it just won't be as efficient as a good outdoor reset system, let alone as comfortable.

where in canada are you?, i am in vancouver.

leo g

Kal Row

ziggi's artical might fall short

in a house with some teenage girls
you might need to add an open loop domestic hot water
holding tank to the setup or you will run out
hot water - otherwise - insulated holding tanks
are the most efficient things you can do, think
about it, the sun is 900 watts per square foot,
how do you store that? well super-solar houses do it with
septic tank sized underground holding tanks and after
a good sunny day, they can go for three cloudy days!!!

Kal Row

ziggi's artical might fall short

in a house with some teenage girls
you might need to add an open loop domestic hot water
holding tank to the setup or you will run out
hot water - otherwise - an insulated holding tank
is one of the most efficient things you can do, think
about it, the sun is 900 watts per square foot, even a 50%
colector is getting 450W per sq ft,how do you store that? well, super-solar houses do it with septic tank sized underground holding tanks and after a good sunny day, they can go for three cloudy days!!! imagin what it would be if you could store it in a pressurized holding tank at 270 degrees, we havent even scratched solar energy yet!!!

Walter_3

Crazy Idea for Radian Heat.

Hi guys. Thanks for your inputs. However, none of you have tried answering my questions. I know there are other ways (i'm sure better ways) to do it. But I need answers for my specific questions. I live in Brampton and the house will be in Caledon. I just moved here, and i've herd winters are rather cold. So I'm trying to make it nice and comfy in there, with a minimum amount of expence. Pumps are expensive and each one consumes about 80 bucks of electricity yearly I would think. Consider the expence to run it as well as to set it up.
Thanks !
Ps. No i dont' have any teenage girls. Not that I wanna ran out of hot water either

Mark Wolff

Answers

> Hey guys. I have a radian heat Idea. I want to

> ask all of you experts what you think about the

> following. I'm going to build a one story

> building with basement in Canada. Heat Loss

> Calculation shows for the basement around 40,000

> BTU. 5 loops 250' each, 1/2 pex. The first floor

> around 45,000 BTU with 3 zones, each one is two

> loops 250' each. I'll use a regular gas boiler

> and indirect water heater. I have an idea ! What

> if I will use the same heat exchanger to heat

> domestic water and radian heating? I'm going to

> try to connect the heating line into the heat

> exchanger's line between the boiler and water

> heater. Is this going to work? I understand that

> I have to keep the water in the water heater

> around 160F to prevent the condensations in the

> boiler return. After the boiler heats the water

> heater and pomp and the solenoid valve shuts

> down, the heating can use the same heat exchanger

> from the water heater using the water heater like

> a buffer. Now I have a couple of stupid

> questions.

>

> 1. Is the heat exchanger

> powerful enough for use in such system? (total

> load 85,000 BTU) 2. If the boiler begins

> working, the temperature before mixing valves

> will quickly increase up to 185F. Will the mixing

> valves hold selected (say 110F) temperature for

> the radiant heat without a huge jump in

> temperature?

>

> 3. For the basement I'll use one

> zone with one pump. 1st floor will have 3 zones

> controlled trough the zone valves loaded onto one

> pump. If two zone valves will be deactivated

> (turned off by the thermostats), and one zone

> will be left to work how will it effect the pump?

> Is the flow into this zone increase badly for the

> pump? What might happen? Noise? Overloaded pump?

> This system is good for the following reasons (if

> it works) We are saving.

>

> 1. avoid using

> additional heat exchanger. 2. avoid using

> additional pump for this heat exchanger. All such

> system (four zones and water heater) only 3 pumps

> will be used. 3. Because boiler is controlled

> by the integrated thermostat inside the water

> heater, we don't' need any additional controllers

> or relays or thermostats. 4. Domestic water

> will also be separated from the heating system.5.

> We save over 1000 bucks.

>

> Please use as much

> constructive criticism to help me as possible.

> THANKS!

>

> HAPPY NEW YEAR!!!

Mark Wolff

Answers

Whatif I will use the same heat exchanger to heat domestic water and radian heating? I'm going to try to connect the heating line into the heat exchanger's line between the boiler and water heater. Is this going to work?

In theory yes. Several complications are listed below.


the heating can use the same heat exchanger from the water heater using the water heater like a buffer.

First Complication: Now you need a bronze circ pump (read 2-3 times as expensive-there goes the money saved on another cast iron pump). Additionally, Wirsbo and several other tubing manufacturers do not allow heat pipes and dom. water pipes to mix due to taste problems encountered during pipe testing. Make sure the pipe you use for your in-floor is compatable as a dom. water AND in-floor heat pipe.


Is the heat exchanger powerful enough for use in such system?


Depends on the heat exchanger. Remember their btu transfer ratings are based on laboratory temperatures (read 200* plus depending on manufacturer and model) so have the heat exchanger manufacturer pick a suitable exchanger based on your supply temperature and btu transfer required, and pay close attention to their flow rates required to meet that transfer rate.



Will the mixing valves hold selected (say 110F) temperature for the radiant heat without a huge jump in temperature?


Second Complication: No. Mixing valves fluctuate in temperature due to their slow opening/closing. Variable speed injection is much more controlled and therefore more desirable in THIS installation.


For the basement I'll use one zone with one pump. 1st floor will have 3 zones controlled trough the zone valves loaded onto one pump. If two zone valves will be deactivated (turned off by the thermostats), and one zone will be left to work how will it effect the pump? Is the flow into this zone increase badly for the pump? What might happen? Noise? Overloaded pump?


It is actually a common occurance. It will increase the velocity of water in the zone that is open. If the pump is installed in the correct location, and your piping is sized correctly, you should not experience any noticeable noise issues. As long as the pump is not deadheading (running with no zones open and no bypass for water to circulate through) you should be ok. If you plan on living in this house for a long time, you might consider upgrading to type L or type K copper for the main mechanical piping to increase the longevity of your piping system, mainly near the boiler and the pumps.


5. We save over 1000 bucks.


In all honesty, this is probably the only real reason you are considering this design. That and a non-conformist, I'm smarter than everyone else, self-made man misconception. Unfortunately as you stated earlier (if it works!) is the big ?. If you really want to toy with it and find out next winter (the first time the full heat load will be called for) go ahead, but make sure you have the number to a competent heating professional (Find a professional section of this website is a good place to start) near your phone, and lots of extra money to pay them to take apart your "idea", and install a "system".

chuck shaw

A wise man once said

the laws of physics and economics cant mix. In other words, try to do a system on the cheep, and you get what you pay for. And $80 a year to run a circulator, come on, that is about 22 cents a day. Most of us would not even bend over to pick that amount of money up. Just do it right.

Chuck Shaw

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leo g_67

egg-xact-a-tactly

chuck! well said.

leo g