PW ZW comparison

Operationally, they are virtually the same. The cold outputs vary some, the amount of heat varies some, and the warm output varies too, but probably not outside a standard deviation of comparing two 275 units or two 250 units. There is a great real-world test done HERE which appears quite objective. This site, "Tranz4mr’s ZW Page" has a lot of ZW information to digest... enjoy!

Thanks Rob, those were 2 great references.  It always amazes me how you in particular find all those things!!!!

Like I said, the issue that I read only had 5 or 6 sentences so it gave zero detail on top of the one statement that it made.

thanks again - walt

Walt

Keep in mind that in the test that I published on my website even though the zw250 was loaded down almost to the point where the breaker tripped for a decent amount of time the ZW250 never got dangerously hot or even uncomfortable to the l touch. From the first ZWs made until the last they were continuously revised, mostly to lower the cost of manufacturing by reducing the total number of parts to assemble. Through all of these "improvements" they did evolve to run quieter and cooler by the last versions. The last versions if assembled in the factory correctly ran completely silent vs a slight hum of the early versions. Not a huge difference. 

Thanks Kent.  The ZW250 that I have was bought by my Father in 1949 or early 1950.  It works well and doesn't get hot. 

The output comment really caught my eye though as I had considered upgrading to the 750 a few times but never felt it was worth the cost of doing that.

- walt