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Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 7:02 pm
by brckwlt
I have a mono-flow system for aa-130 boiler. I was considering changing it so I could have the hot water continuously flowing throughout the radiators. From what I understand this can save a good amount of fuel and you will have a more constant temperature throughout the house. What needs to be done to make my system a continuous circulation system. Are there a lot of expensive parts? Would there be a lot of labor involved for my plumber, since I cannot plum? If anyone currently has a system like this could you post pictures of your setup, and explain how it works.

I was also thinking about using danfoss valves on the radiators or something similar. How hard is it to put on the danfoss type trv valves onto the radiators? is this something a novice could do? explination of how the trv works http://books.google.com/books?id=HAMbdaR3IvYC&pg= ... q=&f=false

It makes the most sense to me to use a combination of the trv and the continuous circulation system in my home. I think it would help me save some money on coal and keep the house a more even temperature.

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 7:15 pm
by coaledsweat
For those unfamiliar with what is described above.

http://www.comfortableheat.net/pdfs/continuous.pdf

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 8:00 pm
by Sting
To replace the radiator valves -- you will need a spud wrench like this
**Broken Link(s) Removed**You will also need two nice two foot pipe wrenches (I tend to file mine nice and sharp for these jobs so they bite) and two pcs of stout pipe 4 feet long that will fit over the wrench handles to give you some "cheating leverage". A square jaw wrench in nice for installing he new valves and prevent pipe wrench marks -- but ...... I have some proprietor pipe dope that looks like baby poo to that makes these connections a bit more fault tolerant but its all about what you can find amd are comfortable with -- We could start or renew the witch hunt regarding pipe thread sealant again and I just don't want to anymore.

The valves should inter change new for old - but the question should really fall to you

Are YOU comfortable twisting the pipe in your house, and - will you accept responsibility if you twist something off or incorrectly and cause a leek?

As to the continuous flow system -- BRAVO :D :D :D You will love it.

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 8:21 pm
by coaledsweat
Sting wrote:To replace the radiator valves -- you will need a spud wrench like this

As to the continuous flow system -- BRAVO :D :D :D You will love it.
Would he need to change the valves to run a continuous flow system?

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 8:29 pm
by Freddy
Hmmm... just why is a continuous system more efficient than a mono flo? Other than...if some rooms are way too hot, then that's wasteful.

If they are balanced right, a mono flo should give nice even heat to each room. The one (only one?) problem with mono flo is that they are a PITA to bleed, and as air collects in the radiators, then heat distribution goes to heck. I certainly agree that a "regular" system is much better than a mono flo, but if the mono flo has valves on each radiator so you can balance each room, and it's kept bled, I dunno....it's a lot of work to convert, and I've never seen a changeover without swear words, broken parts, and bloody knuckles. With just a little bad luck you'll end up removing at least one radiator and taking it to a welding shop to get a broken nipple out. Yes, it's a good change to make, but it's a huge effort.

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 8:37 pm
by coaledsweat
As I understand it, the flow will be continuous at lower temps than the higher temps of a start and stop system. Why would he have to change his existing valves currently on the mono flow system?

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 10:22 pm
by brckwlt
edit

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 10:33 pm
by brckwlt
Sting wrote:
As to the continuous flow system -- BRAVO :D :D :D You will love it.
Is that sarcasm or are you being serious?
Sting wrote:The valves should inter change new for old - but the question should really fall to you

Are YOU comfortable twisting the pipe in your house, and - will you accept responsibility if you twist something off or incorrectly and cause a leek?
Answer is NO! I don't want to mess up a nipple or damage a radiator. don't have money for that. I don't have two foot long pipe wrenches either. I have ones about a foot long. How likely is it that I would mess up or break something, changing out, up to, 17 valves? I sort of thought it would go like this ... take wrench twist of old valves, put on new. done. very simple. Sounds a little harder then I imagined it.
Freddy wrote:Hmmm... just why is a continuous system more efficient than a mono flo? Other than...if some rooms are way too hot, then that's wasteful.
Elimination of boiler over-firing and
draining of boiler temperature during
circulator start up is eliminated. This allows
higher combustion efficiencies.
All existing thermostats, operating
zone valves or circulators will become high
limit controls taking solar gain and foreign
heat sources (body heat, fireplaces, stoves,
appliance heat, etc.) into consideration, thus
eliminating possible temperature override in
certain sections of the building. Therefore,
none of the existing controls should be
removed. It is strictly a matter of adding a
mixing valve, controller and sensors to the
system.
These systems offer the ability to fine
tune a hydronic system to within a fraction of
a degree in room temperature, maintain
boiler temperature for sufficient domestic hot
water supply if desired. Other advantages:
Elimination of thermal shock caused
by surges of cold return water to the boiler
(with the use of a 4 way valve)The return
water is pre-tempered by the mixing valve.
This increases the life expectancy of the
boiler. Peak Performance of thermostatic
radiator valves, installed in the system is
obtained since the optimum flow temperature
for any of these valves lies within the median
range of 90 to 140 degrees Fahrenheit.
Elimination of circulator startups
prolongs the life of the motor, while
decreasing electricity consumption.
Thats what I read, I know little about this concept but it sounds good to me. it sounds a hell of a lot better then how my system works now. No lows and highs just constant heat. my boiler wont go from high water temps before it fires to very low after it gobbles up my miles and miles of cold water sitting in my huge asbestos 2 and a half inch thick covered pipes. It claims better efficiency and I like that. although coal is cheap. it takes an awful lot to heat my house and im not made of money. I burnt a freaking ton in the month of November alone. I would like to cut that down a bit.

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 10:54 pm
by coaledsweat
Those radiator valves won't do a thing to solve the problem he faces with the massive pipes dumping cold water on that boiler every time the pump starts. Running the pump continuously will probably triple its lifespan as an added benefit. If money is tight, just go for the 4 way valve now and make sure it is one you can actuate manually. A quick re plumb right at the boiler and he can be up and running. You will just have to make a trip up and down the stairs when the weather changes (like you are not doing this now :) ). When you save up enough from not running that AA @ WOT, you can spring for the automatic controls. I will call my plumbing supply house in the morning to see what they have on this. Doesn't look too pricey to me. 8-)

http://www.blueridgecompany.com/radiant/hydronic/ ... xing-valve

**Broken Link(s) Removed**

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 11:11 pm
by brckwlt
I like what I see. a few hundred bucks isnt that bad. im so cheap though I wish the valve cost 20 bucks. haha im sure there is more to it then just putting that 4 way valve on isnt there?
coaledsweat wrote:You will just have to make a trip up and down the stairs when the weather changes (like you are not doing this now :) )
yeah like 4 times a day or more :D

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 11:24 pm
by jim d
brck wy don't you wire the circ to run constantly and have the tt turn the fire on & off this should work unless you have your domestic comming of the same boiler

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 11:31 pm
by brckwlt
I do have the domestic hot water coming from the boiler. but why wouldnt it work like that?

whats the TT?

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 11:41 pm
by jim d
the tt is the thermostat do you have a coil or an indirect for your domestic either way you have to increase the temp to get the dhw out and with constant circ unless there are zone valves you will over heat the rest of the house

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 11:49 pm
by brckwlt
Yes it is a coil for the dhw. why do I have to increase the temp to get the hot water out?

why would the house overheat unless there are zone valves. the whole point of this is so that you can have constant water flowing at a desired temperature to the radiators. 100,109, 120,140,160 etc ... whatever heats the house most efficiently.

Maybe there is a lot more to it then meets my eye. but it doesnt seem like a complicated detailed process. flow the water at whatever temp you want then my boiler isnt slammed with cold water on startups. it takes a very very long time when my boiler calls for heat till it pumps hot water throughout my 17 radiators and massive amounts of heat pipes in the basement.

Re: Monoflow Continuous Circulation System

Posted: Sun. Nov. 29, 2009 11:57 pm
by jim d
if your circulating 125* h2o how are you going to get 120* domestic