With MTH trains closing in 2020, I see that are doing a last run of their HO Scale 2-8-8-4 DM&IR Yellostone type locomotives. I see on their 2020/2021 catalog there are two versions, being the Worthington and Elesco vrsions, with two engines for each type being offered.But what do these mean?
Worthington and Elesco refer to the type of feedwater heater that was installed on the locomotive. The feedwater heater was an appliance that did exactly what it was called, it preheats the water from the tender before it goes into the boiler.
DM&IR got Yellowstones with feedwater heaters from 2 different vendors. The applicance from each vendor looked very different so MTH is offering models with both types of feedwater heaters.
Scott Sonntag
Here's the ELESCo version, with the heater bundle atop the smokebox and in front of the stack, while the cold water pump is set low on the smokebox front, below the bell. (ELESCo is actually an acronym, the EL representing the letter "L", the ES an "S", and the Co the shortform of the word Company, as representing the Locomotive Superheater Company.)
It was more difficult to find a Worthington-equipped one, but I believe this is one of them.
The heater is pretty-well hidden in the area between the bell and the stack, while the hot water pump is located below the two cross-compound air pumps. I don't see the cold water pump, but it may be behind the loco's trailing truck, somewhat hidden by the fairing on the cab steps.
The later Worthingtons (S and SA types) were supposedly the most efficient of the three most common ones in-service (Coffin, ELESCo, and Worthington)
Wayne
There is a difference between the operation of the two systems. Elesco is a closed feedwater heater: the drum is like a little 'boiler' that keeps the feedwater being heated strictly separate from the exhaust steam (which may contain lubricant that would impair heat transfer and screw up boiler-treatment chemistry if put into the boiler). Worthington is an open-type, where the exhaust steam is mixed with the feedwater, and condenses in it, giving both better overall heating efficiency and improved water rate, but at the cost of having to deal with any oil problem.
If you look at the front of the engines, near the smokestack, you can see the difference on the models. The Elesco is sort of a big tube, Worthington is more squared off and lower. IIRC the DMIR got the Yellowstones in 2 or 3 orders, 1 order came with one type of feedwater heater and the other 2 with the other feedwater heater...but I'd have to grab my DMIR books to remember which was which.
ELESCO:
https://mthtrains.com/80-3259-1
WORTHINGTON:
https://mthtrains.com/80-3261-1
The Worthington was considered a more advanced system and would likely have been on the later orders -- I suspect the exchanger was also somewhat cheaper to make and easier to maintain. I am certain that Ed has detail diagrams and pictures of the system components. The arrangements for oil separation on the Worthington system deserve good documentation.
Some information:
DMnIR_2884_M4 by Edmund, on Flickr
DMnIR_2884_M4-fe by Edmund, on Flickr
Style No. 1 being the Worthington S and No. 2 being the Elesco.
Worthington_0001 by Edmund, on Flickr
Worthington layout.
Worthington_HW-pump by Edmund, on Flickr
Hot water pump. The oil separator would be placed at the inlet side near the four studs shown.
Elesco1_zpsdfejh59s by Edmund, on Flickr
An overview of the Elesco system. Most commercial models do not include the oil skimmer detail on the tender cistern deck. There would be a circular access plate with two pipe elbows protruding from it.
Thank you, Ed
So far as I understand, there were two orders. The first group of engines was built with Elesco feedwater heaters. The second was delivered with Worthington SA feedwater heaters.
I ordered both of the Worthington feedwater heater versions.
It's a neat engine and I'm really looking forward to getting them.
John Mock