Burning my first batch of Envi Blocks. Where's the heat?

I bought approximately 20 packs from tractor supply of their house brand. They weight about 7 to 8 pounds each. They put out a lot of heat in my opinion. You have to play around with how you stack them in the stove. How many are you using at once?

i've been trying different ecologs and have found them lacking in burn time and heat output.i plan on sticking with wood

I don't know about envi blocks, I am using Eco Bricks they are roughly 10"x3"x3.5" I have to put at least four of them mixed with wood to get some serious heat out of them. Three bricks on their own wouldn't do anything for me. I think I would have to put at least 6-8 to get heat if I was using just the bricks.

If you get a chance these will burn very hot in your Lopi. They probably are hard to come by back east though.

http://www.northidahoenergylogs.com/energylogs.php
http://www.homefirelogs.com/

I use eco bricks....but 4 stacked in the way you mentioned and get 450 F...if I add another on top, it goes to 550 F. I also like to mix with wood....2 bricks with 2 bigger splits goes to 600+ F. Go slow, adding 1 at a time and find how it works in your stove... Bricks stacked with no air spaces in between burn differently....maybe someone here has pursued that experiment. I burn 4 or 5 to get a nice even heat in a room I don't want to overheat and mix them with wood in the other stove to conserve on the amount of wood we have to process and move. They take up half the space and are delivered to my garage. They are slightly more than wood here. So we use them for the convenience and repeatability and ease in lighting...lean a firestarter next to a brick and light it or on coals they light right up.