can I bypass a baseboard radiator automatically (by thermostat)?

edsut

I just moved to a house that has gas-furnace with hot-water baseboard. The whole house is on one zone with bedrooms at the beginning and living room at the end. The thermostat is in the living room so a "cozy" living room means a "hot" bedroom. I'd like to be able to cool down the first rooms in the circuit. I know I can add zones, but I was wondering if there is a common way to thermostatically disable a radiator (say with a diverter-T and some kind of thermostatically controlled valve)?

hot_rod

fin tube baseboard? Most have adjustable dampers so you could dampen down the overheating rooms.

EdTheHeaterMan

As @hot_rod Bob said You should be able to close the damper on the baseboard. It is #2 in the diagram

Depending on the age and condition of the baseboard hardware, paint and method if original installation, that is sometimes easier said than done. The idea is to block the convection air currents from moving across the heated aluminum fins. F the dampers are not adjustable or missing, you can cover the elements with aluminum foil to accomplish the same thing. Just tare off about 6" inch strips and stuff them unto the top opening of the enclosure the entire length of the element. If it gets too cold then remove a little at a time each day to see if you get enough heat. If it starts to get too hot again, then you can add some back until you get it just right.
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EdTheHeaterMan

Youngplumber said:

Yes a thermostatic radiator valve will do what you need. 

That may not work on a one-loop baseboard system. If you close the valve in the bedroom to stop the water flow there, you stop the water flow to the living room also. Even on a single thermostat multi loop system, if you close the valve in the bedroom then all the rooms on that loop will be without heat.

There is a section that addresses this, that starts on page 20 of:

http://media.blueridgecompany.com/documents/ZoningMadeEasy.pdf

HVACNUT

If you're willing to spend a few bucks, you could split it into 2 zones. Main, and bedrooms. New thermostat in the MBR. You might need some type of bypass to prevent short cycling as well.

EdTheHeaterMan

Youngplumber said:

@EdTheHeaterMan Since he asked about a diverter tee I'm assuming he is not piped in series.

I believe he asked about the diverter tee being ADDED. I don't believe there are diverter tees already there. I believe he was thinking like the illustration at the top of page 21. They are just regular tees in that illustration so when a TRV is closed there is a bypass, and when all the TRVs are open there is less resistance to flow so the majority of heated water flows thru the 3/4" piping.

Look at the bottom of page 21 to see why you don't want to use TRV on Monoflo systems.

EBEBRATT-Ed

@edsut

Go to the store and get a box of tin foil.

Cover a section of the fins in the hot room with tin foil and wrap it around the element. Cover 2-3 feet.

Try that and adjust as necessary

edsut

Wow! Thanks for all the responses! Just to clarify my situation... I have a one-pipe system with all fin-tube baseboard radiators in series. I mentioned the diverter-tee and valve realizing that I would have to install the parallel paths (with the diverter-tee and valve) around the affected radiators. I guess that would make my system look similar to the "modified loop" system shown above.
At my expense, I'll be honest and tell you that I didn't even think about adjusting the damper (yes, I'm a moron); so I'll certainly give that a try first. So two more questions...

1. Does closing the damper just "waste" the heat or will that actually put more heat in the living room?
2. If the damper adjustment doesn't do it, is the diverter-tee/thermostatic-valve plan the next step?

Thanks again!

EdTheHeaterMan

The room that is too hot is wasting heat. Letting heat stay in the pipe to recirculate to another room will save heat

Yes the "Bypass" (not diverter tee. Which means something else in Hydronics.) with a TRV will solve the problem if done properly.
Look at the Zoning Made Easy explanation around page 20 and 21.

EdTheHeaterMan

@Youngplumber
Reverse return is rarely used on baseboard loop systems. Baseboards (the copper tube alum fin type) are usually a single pipe, as the OP stated his is.

Let me say in residential applications Reverse Return is rarely used. Mostly parallel return is found on old gravity systems from back in the day.

When I think of one zone this is what I think of if the house needs more than 40,000 BTU

edsut

Ok, I adjusted the dampers. I'll know in a day or two if that's the cure...
I can't thank you all enough!

bburd

If the dampers don’t do it… Try the foil trick. It costs almost nothing and usually works.

edsut

@bburd, yes I will do that...

edsut

Just wanted to give you guys an update...
The bedrooms are significantly cooler and it seems the living room is a bit warmer.
My problem was solved and I didn't need a tool!
Kudos to all, thanks very much!