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joe001
02-09-2011, 01:08 PM
This spring I intend to replace my current natural gas fired boiler (hot water system), and I want to try to educate myself about products and options before I start getting bids.

I have a small 1.5 story Cape Cod-style home with a finished basement. The basement was finished a few years ago, and the single large radiator was replaced with multiple copper fin baseboards that are on a newly created zone (new copper piped loop). The entire first floor is cast iron radiators, and the top floor is a mix of cast iron radiators and cast iron baseboards.

Question 1&2: I would like to have more control over the temp in individual rooms, or at least the middle and top floors. Does it make sense to place thermostatic radiator valves on every radiator on the middle and top floors? I have plaster walls and ceilings and assume I would need to do some exploratory work inside them if I wanted to do separate zone valves for each floor. Is that correct?

Question 3: When the heating company added the basement zone, they installed 2 zone valves. There is a single circulator pump activated by a surface mounted aqua stat. Please excuse my ignorance, but is that the correct way to do it? There are times when the aqua stat keeps the pump on, but both zones are closed, so the water being pumped has nowhere to go. Recently I noticed the pump is making noise. When I manually open either zone valve, the noise goes away. Is there a controller that ensures that if the pump is on, at least one zone is open?
Thanks.

dirtsprintfan
02-09-2011, 08:54 PM
That is not the way to properly use a zone valve. The end switch should turn the pump on. No need for a aquastat other than a secondary limit. Also try not to mix rads and copper baseboard on the same zone. They won't work right together. High volume rad and no water vol. in the cop. baseboard. Enjoy the new boiler.

joe001
02-10-2011, 11:04 AM
Thanks.
The basement zone is all copper fin baseboard, so no mixing iron rads and copper baseboard.

Any thoughts on the thermostatic radiator valves on every rad vs. trying to zone the main and 2nd levels? Will the walls need to be opened to map the piping in order to zone the house by level? Can TRVs be used instead of zones?

acwizard
02-10-2011, 11:12 AM
There are numerous ways to address your situation , send some pictures of what is there now, more concerned how it is piped. Cast iron has more mass than the copper so it retains heat longer, this is why you do not want to mix them on the same zones.

dirtsprintfan
02-10-2011, 09:39 PM
Zoning the first and second floors will probably be a lot cheaper by just putting TRV and the rads you have. The piping is usual all buried in the floors , so it will be difficult to separate each zone.

Have that contractor come out and wire that basement zone the right way. So the zone valve controls that pump and not just running wild.