adding a radiator

wombosi

I have a studio in the attic in which I'd like to install a radiator. I have them ready to go in the basement left over from the POs.
Right now there are two zones, upstairs and downstairs.

Seems in theory would be pretty easy to pop in a new one. The question is, how do I find out of my boiler can handle the extra BTUs?

Would you install this last radiator at the end of the upstairs zone, or put it on a whole new zone?

What about tacking it on to zone 2, but install a shutoff valve (assuming the room will not get a lot of use)?

Thanks.

tk03

I would add it as a separate zone. That is the easiest way to control the temperature up there and then you can turn it up or down as needed.
The amount of radiation on a boilers within reason does not matter. The boiler just needs to meet the heat loss. If it worked OK before it should still be OK. If all the home or any zone is cast iron radiation, verify there is some boiler protection. See link.
http://www.comfort-calc.net/Bypass_P...laination.html

Scuba_Dave

The problem with adding it to another zone is it will only get heat when the other zone does. So if you go up there & its cold you will need to turn up the other zone. One area may be too warm, the other too cold
In order to find out if your boiler will handle it you need to do a heat loss calc. But a rough idea would be how long does your current setup run to heat the existing space? My system is over sized & can handle more. Is the additional space huge? Does it stay partially warm right now? Is it insulated?

wombosi

thanks scuba dave. you're becoming the "old faithful," man.

not sure how to quantify "how long" boiler takes to heat existing space. right now that attic studio is noticably freezing compared to the second floor, even with the stairwell door open.

like the rest of house, there is no insulation anywhere. i plan on renting a blown-in fiberglass machine and hitting the cieling above that studio, and the floor in the unfinished space (and possible the wall between the two spaces), at least.

downstairs heat zone has a much bigger pipe than the upstairs, i think 1" pipe downstairs zone, 3/4" upstairs. down here, my t-stat generally goes from 50-60 in about 75 minutes on a sub 32 degree day.

running a new zone would be much more work, lots more pipe, drilling through two ceilings, etc...

EDIT: the attic studio is pretty small, about 10'X10'. Would probably only need one 6-8' radiator.

Scuba_Dave

Insulation would definitely help
10x10 is pretty small, so that shouldn't effect to any extreme
Your heating system should be a decent size due to the lack of insulation. My house had R7 & poor windows. As I have added more insulation & new windows the heating bills have been cut in 1/2

You will need to decide if the added cost of running a new zone is worth it. If you insulate everything up there that may very well solve the heating problem, then maybe a radiator on a valve would suffice

My 2nd floor ~700 sq ft has one radiator, drywall is not up, insulation not fully installed (R30 & R38 ceiling, R15-R19 walls) & it stays about 50 up there right now (40 when really cold out). I'm not planning on adding a radiator. We have forced HW right now, and the door to 2nd floor stays closed. The new bath will have electric radiant floor heat. And oif course it's "only" for sleeping

biggles

try catching the temperature of the last pipe out of the 2nd floor run before it heads back down to the boiler.if it is up in the 100F-120F range to make a 68F on the space cutting in right there to bring the return up into the attic might do it.if the temperatures are less going up there you might consider more rads...definitly wrap that attic up to hold what heat you can get.