[an error occurred while processing this directive]
Posted by Heatpro on December 18, 2005 at 12:04:14:
In Reply to: Raypack Boiler cycling Too Often posted by BILL on December 18, 2005 at 09:55:12:
There are a series of posts between Dave and myself addresing the same problem you have with a copper-tube, low-mass boiler.
Basically it is a matter of not much water volume inside a boiler that is easily and quickly heated when there is no place for the heat to go. Dave is adding a tank to give the mass that would have been built into a larger cast-iron or steel boiler that would contain much more water.
The more oversized a boiler for the heat estimate of the house, the shorter the cycles. That is like getting a HumVee to run down to the corner store for potato chips. My boiler has one cycle when the temperature gets below 20F outside; (it is called ON) because the boiler is sized for the heat during the coldest time of year and no more. Short-cycling won't hurt the machine as long it is not making sizzling and banging noises; but it does wear controls faster and lose efficiency.
This happens so often, that I wrote a web page to explain the situation rather than rewrite it several times a year. It is a result of ignorance - not planning to make a problem.
http://64.226.150.132/hydronic/des/start.htm
http://64.226.150.132/hydronic/des/nobang.htm