Steve,

Glad to hear this, as this will be a good feature for eQuest. In the past
when we've performed analysis on condensing boilers, we used performance data
from Aerco's website, such as:

http://www.aerco.com/products/benchmark3-specs.shtml

There is a link at the top for the efficiency curves that take into account
return temperature and part load. You should check with Aerco regarding
using the data, but I'm sure you guys could work out a deal with them and
other boiler manufacturers, similar to what you guys did with ClimateMaster,
to enable us to use custom curves for specific boilers.

It would be nice to have the capability to directly simulate the condensing
boilers in eQuest. It would save us a bunch of additional steps that we
currently use. The current method we use for simulating condensing boilers
is to first pull all hourly heating load and temperature data into a
spreadsheet. Then, we calculate the efficiency for each hour based on the
load and temp conditions, and the Aerco performance curves. Then, we use all
of those calcs to calculate the annual average efficiency, and then we enter
that number into eQuest along with a custom PLR curve and zero standby and
start-up times. The custom PLR curve is a "y = m*x + B" type where m = 1 and
B = 0 so that the effects of part load are eliminated, since my annual
average efficiency number already takes this into account. I believe this
is similar to what Marlin showed us in a training class about 2 years ago.

We usually come up with annual average efficiencies of about 90 to 91 %,
which seem reasonable. Higher efficiencies are available in theory, but they
bump up against the fact that there is usually not much heating load when you
can get away with the lower temperatures required for the higher
efficiencies. Therefore, the really high efficiencies (when present) don't
have much of an effect on the annual average number.

Hope this helps!

One question; if you guys are in the process of adding a few bells and
whistles to the eQuest program, would you mind if we (eQuest-users) submitted
additional "wish lists" items via this forum?

Thanks!

Regards,

James A. Hess, PE, CEM