Radiator Venting

Wcurtis

Am I wrong?

My thinking is vent the radiators fast which closes vent faster allowing steam to fill radiator faster and heat room faster before t-stat is satisfied.

3-column rads with 7 sections and Hoffman 1a at max.

heard different info about 70 degrees in room on coldest day by design otherwise it shouldnt heat all the way across, mine do and they heat good but again is my thinkin stinkin?

ethicalpaul

Yes, you are wrong

Vent the main fast, and the radiators slowly.

If I were doing it from scratch, it would be like this:

1. Install the slowest vents on ALL radiators (like Gorton or Maid O Mist #4)
2. Live with it a few days and find the room that is the most uncomfortably cold.
3. Increase that radiator's vent by one size
4. Go to step 2 until the house is comfortable

You don't want fast radiator venting in general because then it's much harder to balance your system and it can cause undesirable effects such as the steam races to the vent and closes the vent before the radiator is cleared of air.

Also generally, don't pay attention to radiators being completely filled by steam or hot "all the way across". The important thing is how comfortable is the room. The hot radiator is not the goal, the comfort is the goal.

Wcurtis

I thought the faster the rad's vented and closed once seeing steam the faster the room would heat up

Wcurtis

But wouldnt a hot radiator (vent open more) heat the room better than a partially hot (venting slower)?

ethicalpaul

It takes time to heat up a radiator. If the steam races across the radiator to the vent, and closes it before the radiator is full of steam, then how fast do you think that room will heat up?

Why are you in such a hurry?

The thermostat calls for heat when it's like 1 degree below the setpoint, just how fast do you need that 1 degree back?

KC_Jones

Wcurtis said:

I thought the faster the rad's vented and closed once seeing steam the faster the room would heat up

I guess we need to understand your goal.

Do you want it fast, or comfortable?

Fast will overshoot the thermostat, pretty much guaranteed. So set it for 70, end up at 72, then it will wait to drop to 69 before it fires back up again, lather, rinse, repeat. It most likely would be worse when it's warmer out. Before I got mine under control I'd see 74-75 on a 68 setpoint.

For me the point is comfort. It doesn't take any extra fuel to be comfortable.

Wcurtis

My whole point for this question is because my living room (biggest in the house and also the coolest), so i was looking to heat it better by opening the vents more but sounds like I'm backwards in thinking....hence my question

ethicalpaul

Yes have a look at the ones that are hot or too hot and slow those down

Jamie Hall

One other important bit here -- it doesn't matter how fast the radiator heats up, but how much of it (and by extension, how big it is). The heat released into the room is entirely dependent on that, and how long the radiator stays hot -- not how fast it gets hot.

Steve_175

Is the living room radiator the farthest away from the boiler?
Are all the pipes in the basement insulated?
As others have asked, are the main pipes in the basement well vented?
If the main pipes in the basement fill up quickly then the risers leading to the various radiators will get steam around the same time heating the house more evenly.

dabrakeman

Do you feel your living room might be under radiated? Thus, you are trying to vent it faster than the other rooms? I have a similar issue in one room where I believe the original radiator was removed and replaced with a smaller one to make for more usable space in the kitchen. Best remedy would be a bigger radiator but in the mean time I have kind of taken your approach purposely venting the radiator faster than the others in the house. I have, however, tried to limit the vent rate such that it very rarely closes its vent on a normal cycle. Having it close too early with too fast venting (in addition to potentially not heating the radiator evenly particularly if you have water+steam compatible radiators) promotes getting wet steam to that radiator if your boiler piping is not perfect and can just cause wear and tear on the vent. If you could vent it to just close maybe on 1 degree recovery cycles and slow your other ones down to even the heating in the home while at the same time maximizing your speed to closing main vents I think you will find the best equilibrium for comfort and efficiency in your situation. This will take some trial and error but start with the main first.

Wcurtis

The living room rads are on the longer main and in the biggest room, all mains are insulated and all Rads heat well its just the living room is too cool.

I have slowed all rad vents on this main except the 2 in the living room ( also slowed these down from 6 to 4) per others recommendation but I cannot tell much difference.

All mains appear to vent very well after adding a Hoffman 75 to the Big mouth on the longer main

My next move is to isolate one Rad on this main in an unused bedroom in an attempt to move more energy into the living room rads.

Wcurtis

there is one large rad in the kitchen on a different main that I plan on moving into the living room (the kitchen currently has a metal cover and only one side is exposed for heating) this came with the house so I suppose they felt it was too hot and places the cover over it

SteamingatMohawk

Are you using any Heat Timer Varivalves?

dabrakeman

The balancing process can be fickle and sometimes counter intuitive. For instance, sometimes slowing one rad on a shared main or riser does not necessarily always increase steam to other rads on the same main. For instance I have a bedroom rad that is on the same riser as my sons bedroom radiator. His is usually off and mine has a Ventrite 1a I have on setting 4. When his radiator is turned on I have to turn down my radiator to setting 1 or 2 to have the same output. If I leave it on 4 it heats up way to much. As I say counter intuitive, maybe. I think what happens is that the total venting between the rads on that riser (and likely similal in the case of a main) can affect the draw of steam to that riser or main in total as compared to another main on the system. Just be patient and in my opinion having adjustable vents is helpful.