Hey Ed, Is There Much of a Difference Between the Thermal Balance Point on a HP That We Calculate Versus We Observe in the Field?

In this edition of "Hey Ed," Ed talks about the difference between the thermal balance point on a hp that we calculate versus we observe in the field.

Hey Ed, is there much of a difference between the thermal balance point on a HP that we calculate versus we observe in the field? If you mean HP as in a heat pump, there absolutely is. And this is one that has kind of come to light even more as of late. And it’s one that I think needs to be addressed. When we use the proper process to determine the thermal balance point of a house that contains any heating system, but specifically we’re talking about a heat pump right now, we are going to look at the heat loss via manual J. And it’s not at all uncommon for manual J to have a heat loss greater than what exists in reality because of the inherent safety factors that exist in manual J. It’s not padding, it’s not unnecessary extra, but it’s simply the way manual J computes the heat loss that is taken into account and can create a heat loss that’s just a little bit higher than what might be there in reality. And that’s the way I see it.