On 20 Feb 2005 18:18:40 -0800, wrote:

Here's another rule of thumb:

"Around 37 F many heat pumps reach what is called the balance point. At
or near this temperature the heat pump needs to run constantly to
produce enough heat to maintain a comfortable indoor temperature."
http://www.askthebuilder.com/294_Hea...ey_Work_.shtml

That is also bull****.

It is called the 'thermal balance point' ( as opposed to the
*economic* balance point I referred to earlier ), and it ENTIRELY
depends on the size of the equipment, in relation to the load.

Given 2 identical houses, side by side, one with a 3 ton heat
pump and one with a 10 ton heat pump, the outdoor temperature where
the 3 ton can 'barely keep up' will be very different ( higher ) than
the temperature whre the 10 ton system can barely keep up.

In either event, below the 'thermal balance point', the heat
pump is STILL putting out economical heat into the house, it simply
needs another source to add MORE heat.



Paul ( pjm @ pobox . com ) - remove spaces to email me
'Some days, it's just not worth chewing through the restraints.'

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