need more venting!

ChrisJ

I have two radiators that I was not happy with the amount of heat I was getting from them during the winter.  The radiators work, but these two rooms are rooms I want warmer than the rest of the house and instead they are cooler because of the length of piping.



One is in our 2nd floor bathroom and the other in a small 2nd floor bedroom.  Both are 28sqft EDR if I'm remembering right, however they also both have a pretty long pipe from the main.  Each having a feed that is probably around 20 feet long using 1 1/4" for the horizontal takeoff from the main and then 1" up to the radiator.



I have not insulated them yet but plan on it once I get the time to do so.  All of my rad vents are Hoffman 1As.  These two radiators I have the 1As wide open and it just doesn't seem to be enough.  I'm thinking of swapping the 1As for Gorton Cs on these two radiators.  The thing is, would this be a good idea or should I drill and tap for a second vent higher up on each radiator?



I have plenty of main venting and am adding more before the fall.



Thank you for your time.

Boiler Talk

Need more Venting?

Maybe you need a different vent.   Insulation on the pipes will help it heat faster. Maybe you can adjust the other vents down and leave these two at max. Unless they are already set in this manner. 

gerry gill

I don't know if it will help your decision,

but i use more gorton C vents than anything else...and yes, insulate those pipes.

Hap_Hazzard

How are the other radiator vents?

I'd also recommend a Gorton C or even a D if necessary, but also check the sizes of your other vents. Make sure that the radiators nearest the thermostat aren't getting a big head start on these two, because when they heat up they'll shut the system down, and if they're big radiators they'll keep it shut down for a while. The radiators nearest the thermostat should always have the smallest vents.

ChrisJ

the other vents

Gerry,  actually it does help me as it gives me an idea of what other guys use overall.



Though I have to be careful.  All of the vents are Hoffman 1As which I installed new last fall.  As some may remember, when I first fired the system up I had balancing problems.  I had two radiators which refused to heat at all 99% of the time and all of the 1As were wide open.



Over a period of about 2 months I went around slowly adjusting things.  Most of the 1As are set around #3 or #4 depending on the situation and I have two which are venting as slow as I could get the 1As to vent after a lot of tweaking. 

The two radiators I wish to vent faster are two of three which have the 1A wide open which is why I'm thinking a Gorton C or maybe even a D is the ticket? 

My concern is what are the chances I'll end up with spitting?  I remember Dan talking about drilling and adding a second vent up higher to vent the rad fast until steam hits the top vent. 

gerry gill

i havent had the spitting

Problem with a gorton C.. Ive only had that issue with heatimer vents.

Hap_Hazzard

Hoffman 1A

If I remember correctly, Hoffman 1A ranges from .026 to .225 CFM at 2 oz., so it's slower than the Gorton C (.36 CFM) even when it's wide open. It's even a little slower than the Gorton #6. I tried adjustable vents too, thinking they would make balancing easier, but they just don't give you enough range. The Heat-Timer Varivalve has a wider range, but Gerry's experience is typical. They're spitters. They're floatless and there really isn't much to them.



Still, the Gortons are pretty pricey, and I didn't want to buy one and have it turn out to be the wrong size, so I settled on the Maid-o-Mist vents, which are kind of a cheap knock-off, but they come in all the same sizes as the Gorton radiator vents. I figured I'd experiment with them and use them until they failed, then replace them with the Gorton counterparts. Aside from being cheap, they have another advantage for balancing. They have a removable port, and you can swap them out. If you install one and then want to try a different size, you can change out the port instead of the whole valve, which is great when the valve is in a tight location. Also, if you have two slow radiators, and you're not sure if you're going to need a C or a D, you can try one of each, and if you decide the C is too small and you really need two Ds, you can take the C port out to your drill press and run a size 13 drill through it. :-)



So if you're reluctant to plunk down the buckage for a Gorton vent, give the M-o-M a try. I don't recommend drilling and tapping a cast-iron radiator if you're not experienced with this kind of work. Cast iron is higher in carbon than steel, and it contains silicon, which is tough on your drills and taps. It's hard and has unpredictable fracture characteristics. It's a lot harder to work with than malleable cast iron fittings, and if you screw it up, it's harder than hell to weld.

nicholas bonham-carter

Slower rads

Increase your main venting first. Make sure your back-pressure of venting is down to a couple of ounces. Then if needed, put gorton c' s or some larger vent on the slower radiators (even a mini antler with left over vents), to see the effect.--nbc