Antifreeze in pipes?

Balazs

Hi,
We have recently added two baseboard rads and the piping could only be installed in the crawlspace under the house. I have put polyethylene insulation around the pipes everywhere.
We live in north Jersey and winter can get though here. Someone suggested that we should put antifreeze in the pipes.
Is it really necessary? If it is how so I do that?
The only point of entry into the system is the water feed.
Or maybe through the "backdoor" where I let the water out of the system?
thanks,
Balazs

john notte

> Hi, We have recently added two baseboard rads

> and the piping could only be installed in the

> crawlspace under the house. I have put

> polyethylene insulation around the pipes

> everywhere. We live in north Jersey and winter

> can get though here. Someone suggested that we

> should put antifreeze in the pipes. Is it really

> necessary? If it is how so I do that? The only

> point of entry into the system is the water feed.

> Or maybe through the "backdoor" where I let the

> water out of the system? thanks, Balazs



propolyne glycol specially made for hot water and chilled water HVAC systems is sucessfully used in many commercial applications in which freezing may be encounterd (IE: package chiller systems and water systems which incorporate hot water coils subject to air temps below 32 degrees f.)It is also found in residential systems especcially those which use a snow melt loop off tied into the homes central heating plant. There is a rule of thumb as to the amount of glycol in the mixture. This is gauged by the lowest temp in degrees farenheit the mixture will withstand. There are also two protection levels called "freeze protection" and "burst protection". The percentile of glycol required for these two levels of protection are listed by the manufacturer of the product. In large systems a refractometer is used to indicate when the freezing point of the soulution is adequately low to prevent problems. Another way for small systems is to calculate the total system water capacity and the percentile mixture needed, drain the system, add the reqired amount of glycol through a tapping in the boiler and refill with "city water".
The rule of thumb I use in New Jersey is burst protection to -15 (minus fifteen) degrees farenheit.
Most good glycols have anti-corrosion additives as well.

Heres are the downfalls of using glycol:
* You will loose heating and feul effiency with glycol soulutions as compated to straight water due to the solution having a lower specific heat value.

* he total head on the circulator pump will be increased which can effect flow rate.

* At the minimum_you will need to install a backflow preventer. This is not adequte in most cases and in your case the system can in no way be connected to potable (drinking) water, therefore the city water feed must be removed and the boiler system isolated. It then will be filled to a cold fill pressure using hoses and a transfer pump.

A better soulution in your case woud be to install a simple heat tape and leave the glycol alone.

Drew_2

Glycol Heat Loss

John
Do you have a firgures on how much heat loss there is with various solutions of glycol?

Balazs

So I definetly need some solution against freezing or the hot water circulation will keep the pipes warm?

Thanks,
Balazs

Roland_4

Antifreeze

It's a tough choice. Anti-freeze mixture will protect the pipes in case of a power failure,but,I'd be uncomfortable with even the remote possibility of contaminating my drinking water. Heat tape is certainly safer,but,what if the power goes out long enough to cause pipe freeze in the crawl space. Constantly circulating warm water through the piping will keep them from freezing,but,again,what if the power fails? How cold does it get up by you? I have one pipe run through an un-heated garage. The pipes are heavily insulated and seem to have survived more than a few bitter cold days,but,now I'm thinking about the consequences of an extended power failure. Hmmmmm.

Balazs

Weather

According to the link below on average it does not get colder than 15 Farenheit. Record cold could be below 0 Farenheit.
It's good you mentioned the power failure possiblity. I didn't even think of it.
Balazs

http://www.wunderground.com/NORMS/DisplayNORMS.asp?AirportCode=KCDW&SafeCityName=Lincoln_Park&StateCode=NJ&Units=none&IATA=EWR

Douglas Hicks

If you decide to use heat tape, read the directions and install the tape according to the directions. Several years ago, the heat tape on a roof drain set fire to the local high school. That incident got the maintenance department to check the other schools. One more heat tape was found to have problems, and replaced.

Fireguy