Single Pipe Steam Heat Radiator Vent ID and Replacement Rec

MikeC_3

As per my previous inquiry, I replaced the non-functioning, undersized main valve on my mother's heating system with a Gorton # 2. Whether the ideal fit or not, it sped up the heating time by about a third and reduced gas consumption per week by about 25%.

The only major issue now is two runs of baseboard heat on the first floor furtherest from the boiler in rooms that were "modernized." They still take around 25 minutes to heat up end to end. One is 8 foot in length, the other is 10. They are off a main run of 1 1/2 inch pipe approximately 18 feet.

Using the formula in the G & P guide to balancing, I calculated that they would require a Gorton C or D. However, upon closer inspection (which admittedly, I should have done first), I now realize that these units are vented in a different manner. From reading up in this forum, it seems like this is the preferable way to vent long runs of baseboard - as a two pipe system, allowing the condensate to flow more freely.

So, how does the current configuration affect vent size, if at all? .

Also, the current vents are 3/4 inch and what I believe to be main line type. I haven't had the chance to remove one to inspect it more closely. Is this scenario possible - could they be main vents? Do they make 3/4 radiator vents (not that I have found)? If not, what would be appropriate?

Thanks!

Steamhead

You're right. That looks like an old Flair vent, but it's 3/4". 3/4" convector vents do exist however, and they vent more slowly than main vents.

Since Hoffman has moved production of air vents to China, with accompanying drastic reductions in venting rates (hey @gerry gill, any way you could test them?) I no longer use or recommend them. But you might try a Vent-Rite #35 or #75 on those baseboards to see how that works.

But that would still leave the problem of differing thermal behavior between those baseboards and the cast-iron radiators in the rest of the house. This can cause uneven heating.

MikeC_3

So, there is no issue with using a main vent on a radiator?

@Steamhead - either of those Vent-Rites would work, but if my calculation is correct (BIG if) , they might be a little on the slow side. Does the method of piping have any effect on vent sizing?

As far as uneven heating, I am not shooting for absolute perfection. Just hoping for less consumption and somewhat even heating so my mother isn't shutting every door in the house. Moving in that direction with everyone's help here!

Any idea of the venting capacity of this heap one at Lowe's? Figure I could spend $16 just to see what happens before splurging.

https://www.lowes.com/pd/Durst-Silver-Hydronic-Baseboard-Heater-Accessory-3-4-in-x-1-2-in-Straight-Quick-Vent-Steam-Compatible-Large-Fixed-Vent-Easy-Installation/3535250

ethicalpaul

Don't buy vents from big box stores