Gravity Hot Water Heating [RE-wrenches]

[James Lamb, Middle Fork Engineering]

I came across an English Tudor Home built is 1928 with a gravity hot water
system with and old Red Flash Coal Boiler.
There is a conversion Natural Gas burner that was adjusted to 80 %
combustion efficiency (combustion analyzer)
A Bell & Gussett pump P3-6 1-1/2  was added in 1955 That circulates the huge
volume of water in the system. 
The radiators are huge and the pipes in the basement are 4-5 inches in
diameter. The radiation area is huge and the temperature that
the system operates is very low and gives the occupants that low temperature
comfortable radiant heat. Also, the low temperature enables the condensing
boiler to operate at a higher efficiency.
This boiler is used for backup heat and will heat the house on manual and
the gravity hot water will move through the system 
A hydropulse boiler was added and is very efficient 94-96%  
The house has good southern exposure for passive solar and the owner is
looking into Photovoltaics in the future so its conservation
time. 
The existing circulator pump take a lot of electric power and we want to
change it.
What would be the most efficient pump that could be installed on this
system?
The pipes are big so the flow resistance is small  
Jim Lamb
Middlefork Engineering
 

----------------------------------------------------------------
The information transmitted is intended only for the person
or entity to which it is addressed and may contain confidential
and/or privileged material.  Any review, retransmission,
dissemination or other use of, or taking of any action in reliance
upon, this information by persons or entities other than the
intended recipient is prohibited. If you received this in error,
please contact the sender and delete the material from any computer.

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://www.topica.com/lists/RE-wrenches/

List rules & etiquette: http://www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

==^================================================================
This email was sent to: michael.welch at homepower.com

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9
Or send an email to: RE-wrenches-unsubscribe at topica.com

T O P I C A -- Register now to manage your mail!
http://www.topica.com/partner/tag02/register
==^================================================================