Slantfin Multi/Pak Baseboards

Joe V_2

How well do these work?  I have to add radiation to unheated rooms and prefer to use baseboards if possible but there is not much out there for steam baseboard, even on the slantfin site.  Seems like it is possible but they prefer to use hot water.

Steamhead

I've used them for steam

specifically, Vapor which is 2-pipe. As long as the existing radiation is low-mass, such as convectors, the Multi-Pak 80 with the steam-type element having black iron pipe instead of copper will fit in nicely. If this is a one-pipe system, you'll have to run return lines from the Multi-Pak to the wet return (or use a water seal if you have a dry return)  and pitch the element down to the return end, otherwise it will bang. 



If the existing radiation is cast-iron, the Multi-Pak is not such a good choice. It does not hold heat like cast-iron will, so the rooms with the Multi-Pak will go cold much more quickly. In this case, cast-iron baseboard or traditional radiators are the right choice.

Joe V_2

that's good information

Thanks steamhead!  It is a vapor system that runs on 8oz.  I have not considered to lack of mass letting the rooms cool faster.  The rooms are bathrooms and kitchen and they  comfortable with only electric oil fill radiators from Lowe's as a heat source.  I'll have to give it more thought. 

Joe V_2

oops.

sorry, posted twice

Joe V_2

going with the cast iron but

...there isn't much written about baseboards on a 2 pipe vapor system.  There is enough but I'm still curious.  Why does a baseboard need an air vent on the return and not a steam trap?  

Steamhead

On Vapor

you hook up cast-iron or fin-tube baseboard just like a radiator- inlet valve at one end, and pitching down to the return connection (with trap if used). No air vent is needed since the air exits with the water at the return connection.



If this is an Orifice system that doesn't use traps, you orifice the inlet connection in the usual manner. What type of Vapor system is it, BTW?



On a one-pipe system, you use an air vent at the far end of the baseboard, but you need a return line since the water doesn't have enough room to flow back against the steam in the baseboard. In this case the return line only carries water, not air, and a steam trap won't work because it would let steam flow up the return and close the air vent. That's why a water seal or a wet-return connection is the way to go when using baseboard on a one-pipe system.

Joe V_2

But...

In TLAOSH, it says traps wont work. Did I misunderstand it?I have valves on existig rads and it is a Trane system

Steamhead

If you're referring to

the discussion on page 99, that only refers to hooking up baseboard on one-pipe systems, not Vapor systems.



On Vapor, there must always be a way to keep steam from getting into the dry return. The most common way to do this is with a trap. So if the entire Vapor system has radiator traps, you'd use a trap on your baseboard.

Joe V_2

Thank you!

Steamhead, thank you for clarifying for me!  I didn't think it made sense.