Owners of new stoves some other things to consider, If you have FHW heating system.. Read on to my f

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elkimmeg

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For most of us the cold has not arrived yet. Most will try to get the most heat out of their stove effectively shutting down your forced hot water zone or zones.
Have you thought about some sort of freeze protection. Many times hotwater pipes are routed in exterior walls and at times threw overhangs.
If the water is not circulating, all it takes is one sliver of cold draft to freeze your pipes. Since you burner cycles far less, water will be sitting in your pipes with
out movement a lot longer. It is possible these freezing condition existed but circulation never allowed the exposure time to freeze your pipes
In comes that wood stove, it is so effecient heating the zone it is set in, that it the thermostat rarily calls for heat.

There are three know ways to adviod freeze ups,
One would be to install a freeze alarm to warn you ahead of time freeze condition have deen detected.
The second way to prevent freezing pipes it to charge the system with antifreeze
Third, find the temp setting of the thermo that allow enough flow to prevent freezing. This will take time and experimentation and is not as fail safe as the other two
Having auto setback thermostats and wood stove really increases your chances of freeze ups.

Knowing the sounds made by normal burner opperation can also alert you. IF you hear loud banging pipes noises, That is from rapid expansion and contraction,
when hot water bumps into cold water and pipes. hopefully not frozen already.
 
Great topic Elk!! It's definitely that time of year.

I don't have a FWH system, but I did run into problems with my external water spout on my home. I assumed they had installed a frost free valve. Well, first winter the pipe burst. To make it even better, I was away from home. I get a call from my fiance and she's hysterical. Luckily I have a friend who is quite handy, and he went over, shut off the main, cut back the drywall, and replaced the pipe/spout with a frost free valve.

Shesh, what a problem!!!!
 
Good reminder, sometimes we can get a little overzealous with our burning! Here, all heating and water pipes are on internal walls, except for the 2 in the laundry room and the feed and return on attic air handler. Those pipes are covered in foam insulation, with fiberglass over that. I also try to let the house heat circulate once a day or so at the minimum, for exercise. Plus, it doesn't get rippingly cold here like you'll get up in Mass and the rest of the frozen north, the Atlantic Ocean tends to moderate things a bit. When I used to live in West Springfield, Ma... now THOSE were some cold assed mornings. Thank God for the block heater on the Jetta!

-- Mike
 
When we install a new hearth product (regardless of the fuel type) in a home that has Hydronic heat, We offer the customer a free a stat on the zone or zones that have a chance of freezing. Its a simple cliks on that is normally open and then closes on a temp fall below 40 degrees. its mounted on the pipe in the living space inside of the baseboard in an are we feel could be open to problems .Its wired parallel with the thermostat. Pipe gets to around 40 degrees it fires the heat and circulates the water thru the pipes.

Just keeps the pipes from freezing moving water in a heating system cant freeze.

It is also the job of our installation crew to take the time and explain to his customer that in frigid weather this is a major concern

Good stuff here
 
I had anti-freeze put in my system when I finished the upstairs

The guy that plumbed the house (unfinished up) didnt leave enough clearance AND didnt insulate the pipe on the supply pipe for the upstairs.
The heat guy told me I had two options
One tear out the wall at the pipe and insulate.
Two put anti-freeze in the system (his recommendation)

Knowing I would eventually be getting a woodstove I opted for #2

Know I just have to make the heating system more efficient for heating water.
 
There is an idea for someone to invent something.
Some sort of pump in line with the FHW line that does nothing more than move water thru the pipes.
 
babalu87 said:
The heat guy told me I had two options
One tear out the wall at the pipe and insulate.
Two put anti-freeze in the system (his recommendation)

Watch out for this, it's a common misconception. Insulating an unheated pipe, or space, doesn't make it warmer, and can in fact cause it to freeze faster.

Insulation will keep heat out just as well as it will keep heat in.
 
Great topic, Elk.

I have 3 heating zones in the FHW system, only one of which is particularly subject to freezing. Fortunately, its the one zone that is the furthest away from the stove (it's also the zone I was having problems with a few weeks ago, that you guys helped out on), so that zone tends to circulate fairly regularly.

Any tips on how to add the anti-freeze? How do you get the mix into the water supply? would you drain the system and then gravity feed it into the boiler (at the water supply valve) and then refill the system? My guess is most any type of automotive anti-freeze would be OK, since it shouldn't do any damage to the copper pipes, or the circulating pump. How much should be added?
 
TedNH said:
There is an idea for someone to invent something.
Some sort of pump in line with the FHW line that does nothing more than move water thru the pipes.


No need to invent it, We already have it, Its just a matter of installing some relays.

Unfortunately the plumbing and heating guys don't see the need to offer them. And the hearth guys don't understand how to install it or they may not be licenced to work on a heating unit.

I am not one to suggest the anti freeze as what might be a simple repair on a heating unit become real expensive when your service guy has to recover all of the anti freeze and then re-check whats it capable of protecting down to, Decide how much more anti freeze he has to add to the system to give you the proper protection. Then re-inject it into the system and purge out the air. Then properly dispose of the extra that wasnt injected in.

Any system running anti freeze had better have a approved *back flow prevent er* on it or you can be liable for cleaning up the entire water supply pipes in your area.


*** A back flow prev enter is installed on the water supply line of the boiler, If the water pressure from the street drops below 15 PSI ,it opens a vacuum breaker that does not allow the water from the heating system to be sucked back into the street water supply. Now you may say my boiler is in my basement how can it suck the water out. Well it happens all the time. Anybody with a well could have the same problem if there is no check valve on there well and you have a power failure. Even if the antifreeze didn't make it into the street it could still be sucked into your domestic potable water lines.
 
EDIT: fastrac beat me to it, but we're on the same page.

You can add the antifreeze by pouring it into the system from a high point on the system. Most heating system antifreeze should be mixed in at about a 40 percent ratio (40% glycol). Another way is to pump it in with either a specialized hand pump or an electric rig.

Don't use automotive antifreeze. It's toxic and once it goes into your heating system, it presents an environmental hazard if it's ever drained out, especially by someone who either thinks it's water or thinks it's non-toxic heating system antifreeze. A broken pipe could create an environmental problem for you and perhaps even your neighbors.

If you have a domestic hot water coil in your boiler ABSOLUTELY DON'T USE REGULAR GLYCOL. Under certain circumstances, that stuff could get into your drinking water supply and either kill you, or make you wish you were dead.

Hydronic system antifreeze ain't cheap, and it has the potential to cause other problems in your system over time if the ph gets out of whack. And it needs to be replaced periodically. Most p/h professionals advise you to stay away from antifreeze if you can. If not, use the right stuff.

TedNH--All you have to do to continuously circulate water through your system is to bypass the aquastat and the thermostat and just wire the pump directly into the household current. It will run all the time if you do that.
 
Great Topic ! this has been on my list of things to do.

Short of calling a heating system guy in, is there a tool to test for antifreeze? I remember as a kid my dad had something to check the antifreeze in his car - a hygrometer I think? Does something like that work for heating system antifreeze?

Or should I just drain a little out and put it in the freezer overnight? ;)
 
What you want to test for is ph, not necessarily freeze protection. As you mentioned, you can check that yourself with a common household appliance. But to test for ph, probably the best approach would be to take a sample down to a plumbing & heating supply place and ask them to check it out. If they tell you what the ph is, you can double-check it yourself with a garden test-kit. You know, trust but verify. Here's a great plumbing & heating board:

http://forums.invision.net/index.cfm?CFApp=2l.

Very helpful people; most of them appear to be hvac pros.
 
I have to differ a bit with Eric the antifreeze I use it an RV type. Panadol is one brand, it is not all that toxic and made for these situations. The anti check valve is a good idea.
The place I differ is if your boiler is tankless it has a sepatate hotwater coil and should never get mixed into the domestic side. It is completely independant to your heating zones water
There are litmus type test strips, that can tell you the antifreeze concentrations and ph balance of your system. You only need to draw off a few onces to test it.

As for feeding a system, on a previeous post, I detailed how I did it with a submersiable pump resting in a 5 gallon bucket. The final result is I can pump and feed the zone to completely bleed it and just use the shutoffs and be done. I set my system up to be able to completely isolate zones and leave them fully charged. I do not have to drain the entire system to work on any of the plumbing. I am working on a pressurized antifreeze tank, to automatically charge the system in front of the variable feed valve I have a separate feed in for the tanlkless system. And I have no need of the backcheck valve, as the water supply to the variable feed valve is turned off with a ball valve.

About two weeks ago I detailed how I did this in a post answering NYsoapestove reply to colin More info on this can be found in the green room

a circulator bump idea is also a good solution .

People with forced hot air systems: You are not out of the woods here either If you stove shuts down a zone the remote reaches where kitchen sinks have plumbing in the exterior wall in the cabinets also can freeze. Dymanics of heating now has changed isolated remote water pipes are more suceptical to freezing. one might think about leaving vanity and under kitchen sink cabinet doors open.

so how do you know if a freeze situation is about to happen. I would place my hand under the fawcet the most remote from you heater (this is for the nights in a cold snap where it is going to get really cold and wiind also plays into it) and feel thee temps of the water you will sense when it is colder than normal both the hot and cold water. If I suspect it being too cold then I crack the fawcet to create some running water movement. again If I suspect the kitchen sink I will do the same type of hand feeling test. I would rather pay a little more on my water bill than pay thousands in water damage from a frozen pipe. I know some who have aimed a small electric heater at under the sink pipes.


this whole post is to make you aware things have changed and to start checking and monitoring the effects of change. Doing so can adviod thousands $$ in repairs


And I agree with the poster about pipe insulation its a two way street again circulation is the key to make the insulation effective to preventing freezing
 
Id start thinking of charging that system with anti freeze. There is know way to telling in advanced how exposed your system is to freezing. Especially exposed to periods
of long inactivity, as your stove carries the heating load. Once a day may not be enough. Are you planning to get up at 3:45 Am every day the temps drop below 15 degrees to circulate the system? I cannot tell you the nunber of times it needs to ciruclate to be safe. My home I have 30 years of getting to know what is up. Yours there is no history with the effects of the stove.
mine has frozen 4 prior times. Finally I got sick of chasing down freeze ups and installed antifreeze. My next step was ripping out plaster walls and ceilings, to find and re route pipes
Antifreeze was a cost effective solution

solution #1 install a freeze alarm it will tell you when you need to circulate that system some will allow you to remotely to call in and monitor your system even allow you to triger it
others will actually dial your phone to alert you and detected possible freeze up conditions
 
My main point was not to put automotive glycol into a domestic heating system, particularly if you have a domestic water feed and/or a domestic hot water coil in your system.

What's the code on that, elk?

My guess is that it would specify heating system antifreeze only, and that "not all that toxic" is no substitute for "non-toxic" in codeland.

Anton: If you've got a gravity feed hot water system, then I'm guessing you've also got cast iron radiators. That's a dilemma, because if they freeze you've got an expensive mess. They also hold a lot of water, so putting in 40% glycol is going to run into some bucks. I did that once in my old house, and I think it was about $500. Probably worth it for the peace of mind if freezing is a danger. A bad freeze up would cost you thousands.
 
Agree common auto antifreeze will ruin you coil and is not to be used in your heating system RV type can
 
Not all systems will take the anti freeze. Years ago weil mclean had a boiler with rubbers between the push nipples. The rubbers sweeled from the antifreeze and all of the boilers got leaks.
 
I thought the beauty of push nipples is that they are a metal-to-metal compression fit, and thus not subject to the kinds of problems you get with gaskets.

Hey, learn something new every day. My old gas boiler is a Weil-McLean. Glad I decided not to glycol it up.
 
Eric Johnson said:
I thought the beauty of push nipples is that they are a metal-to-metal compression fit, and thus not subject to the kinds of problems you get with gaskets.

Hey, learn something new every day. My old gas boiler is a Weil-McLean. Glad I decided not to glycol it up.

Not all of them have the rubbers, If you have the old manual to it,they all have a parts break down showing the sections. If it shows the rubbers your out of luck.
 
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