Two recent stories about heat pumps on CBC.ca/nb drew lots of online comments and revealed some confusion about the units.

Ted White teaches engineering technology at the New Brunswick Community College and knows a lot about heat pumps. White read those comments and came up with six heat pump myths that needed to be busted.

Myth No. 1: Anybody Can Install One

Many people can. But, says White, it's all about the warranty.

"The first thing we looked at was making sure you have a reputable installer. Because of warranties. A warranty is not going to be worth anything if you don't have your installer around in 10 years, when something happens."

Myth No. 2: All houses treated the same

"Actually, you need a proper design and sizing for your home.

Ted White teaches engineering technology at the New Brunswick Community College. (CBC) When you take a basic bungalow layout, you're going to have a main area that's open. This works really well for a heat pump. We're dumping a lot of heat into a big open area. And we can let the heat migrate.

"Make sure you keep the doors to your other rooms open."

Houses that are divided up into lots of little rooms often need more than one air handler, which is the part of the unit inside the home. This can make it less economical.

If you heat through hot air vents in the floor, you can replace your oil system, or your gas system with a ducted pump system. It is a bigger system, with a bigger price tag.

Myth No. 3: Bigger is better

"Getting a bigger unit isn't going to help push the heat through, "Ted White says. "It will just make one room hotter."

If you need to heat a big house, you may need multiple air handling units in different areas of the house to cover it completely.

Myth No. 4 You need a really good SEER rating

"Your SEER rating is for the cooling side, and that's only important in the summer. Your heating system, which is your HSPF — heating seasonal performance factor — and that's the one that's most important to us in the Maritimes because heating is more important to us than cooling costs."

Myth No. 5: Pumps save most money in winter

"What we want to look at is how efficient it is in the spring and fall, and that's where we're going to make most of our money back on our system. In the really cold months, that's when it's going to be about the same as a baseboard."

Myth No. 6: A heat pump is all you need

"The older systems don't produce heat efficiently in lower-than-rated temperatures. So when it dips below the temperature it's rated for, you would be better to shut it off, and turn on your back-up source. You won't save any money keeping it running.

"With the latest systems you don't have to shut off the heat pumps when you go below what they are rated for. Just have your electric or supplementary system set to kick in if the temperature drops past the set point in your house. With those pumps, it's better to continue to get the most heat out of your heat pump and just supplement it with your backup."

Canadian Mortgage and Housing has a good checklist if you need more: http://www.cmhc-schl.gc.ca/en/inpr/su/sufepr/sufepr_001.cfm