Dunham steam traps

Tommi68

I am getting several end of line steam traps replaced. They are similar vintage but varieties of Burnham Type30, Type30-2 and Type30-3. Should I be concerned if my contractor uses the same Meppco model to replace all of them?  

Steamhead

Are they all the same pipe size?

EBEBRATT-Ed

Those are not Burnham traps they are Dunham traps.

There is a variation in the amount of condensate between different manufacturers of steam traps.

For instance a 3/4" Hoffman will do 390lb/hr

3/4" Sarco 279lb/hr

3/4" Watson McDaniel 340lb/hr

But traps are supposed to be selected with a "safety factor"

But in your case I am assuming this is residential or an apartment building then any F & T trap will probably be within the capacity you need if he sticks with the same pipe size of the original traps.

Tommi68

Yes, all 3/4” piping, and yes Dunham. 

I can’t find a cross reference between the different Dunham traps and their capacity. Anyone know where to find it?

ted_p

Here are the specs for the old Dunham 30 series F&T traps from page 10 of the Dunham General Products Bulletin of Low-Pressure Steam Heating Appliances, which you can find here:

Dunham General Products Bulletin of Low-Pressure Steam Heating Appliances

I don't think you'll go wrong with Mepco traps; when C. A. Dunham ceased operations, Mepco took over the manufacture of all the Dunham steam traps, so in that regard Dunham = Mepco (compare the above with the attached Mepco 30 brochure). That said, unless I'm mistaken, the smallest 30 series trap they currently make is the 30-7, which is an 1-1/2" trap, so your contractor should substitute the Mepco 44-2 (3/4") H-pattern trap instead. Don't let him sell you a 30-7 and bush it down, either. A 30-7 is way OVERSIZE and probably costs more than 4x the price of a 44-2. The 44-2, being an H-pattern trap, is also much easier to service; all of the guts come out attached to the face-plate and you just change it as an assembly, without having to touch any of the pipes.

Tommi68

Great links! I should be receiving the correct size Mepco traps this week. I really hope to get control of our heating with this next batch of traps replaced.