Is your new copper fin tube baseboard always cold, and no matter how much air bleeding you do and how many service techs you call, it won’t heat up? Here’s why your new section of copper fin tube baseboard stays cold, along with a simple solution to fix this problem.
Why is my baseboard cold?
Adding a new addition to an existing home that uses hydronic heating would require extending the original supply and return pipes. That extension can have some consequences. Hydronic pipes designed for supplying and returning heated water to a nearby cast-iron radiator from a boiler may not work effectively when extended to supply a new, lengthy copper fin-tube baseboard zone. One significant telltale sign is that the baseboard will not heat up, regardless of the air purging efforts made.
When faced with this problem, it appears to be an air problem, but it’s not. The problem is when those original 1″ or 3/4″ radiator pipes which were intended to supply and return heated water for nearby cast iron radiators later become extended. They typically will have a no-flow situation because the boiler’s system circulator can’t overcome the pressure drop (friction loss) in the pipes and fittings of the new added baseboard. The water loss causes reduced flow to the new zone, resulting in less or no heat.
How does it get fixed?
We now know that the boiler’s circulator cannot exceed the system pressure drop for the new baseboard pipes and fittings. The solution for this problem is to designate the baseboard as its own zone by adding a zone circulator to the supply pipe feeding the new baseboard. By doing this, the zone circulator will be able to maintain the necessary pressure and overcome the system’s friction loss through the new baseboard zone. Therefore allowing the copper baseboard to be evenly heated and circulate back to the boiler.
To control this new circulator a zone relay with a room thermostat in the new addition will make this all work. By also doing this the system will run more efficient by circulating the residual stand by heated water after the main call of heat. Although the new zone can turn on the boiler also, it’s not necessary to do so unless there is a totally separate complete zone, for example an apartment unit with three or five rooms.
Here’s the video showing the problem and solution.
Do you have this problem?
Have you added more baseboard heaters and can’t get them to heat up? Or would you like to add more heating and have it done right the first time? Schedule a call with Vince.
