I have it set for the circ pump to kick on around 32-34 degrees then the boiler to kick on around 30. I just figured I needed the circ pump to be on first, but that was the extent of my thinking as I really had no idea how it all works. What temp would I set it on if I attached the sensor to the plumbing? Would it matter if it is pvc and not copper?
I would love to stop by sometime, will keep it in mind.
Slash...You want your circulator to kick on at 32° like you have it set based on outside air temperature since you don't have a slab stat. You could actually have it kick on at a lower temp, but you'd have to experiment with it. Mine comes on at 32° only because I have multiple systems running off the secondary output on the weepmizer....
What you have to do from there is to wire the t-stat to the boiler so it picks up the line (Hot wire) from the circulator. This will "Only" allow the boiler to fire if there is power to the circulator. You DON"T want a situation where the boiler can fire without the circulator running. You currently have this possiblity. If you put the boiler t-stat sensor on the return bay loop pipe, Then the boiler will cycle on/off based on return glycol temp. The boiler t-stat has to have differential capability. Not all t-stats are the same. I have mine set with 10° differential. The boiler kicks on at 60° and off @ 70°. This gives me an average of 15 minutes on - 15 minute off to complete the cycle. Even though you are picking up heat through the PVC pipe, it will be consistant. So you may have toplay with the diffential and setpoint of the boiler t-stat to get it dialed in. But once you have it set, it will repeat.
When the outside temp goes above 32°, it cuts power to the circulator which in turn cuts power to the boiler t-stat thus shutting the whole system down...
2Biz I definitely owe you a few beers. I just saw post #35 & #36! I'm sorry for keeping you up at night. As for your question, I have not looked at any other heaters. I did just look at some of the pump data and I was thinking that with two Takagis in series I would need 50 head ft to get the flow through the heaters but 16 gpm total (8 gpm each). I found a Taco 2400-50 will flow 15gpm at 46 head ft using a 1/2 hp motor. It's about a $500 pump/motor setup.
I wished I would have seen this circulator before putting (2) 013's in series. This is a much better pump to handle the job.... It only uses an amp more than mine put together. Maybe I was looking at the ability to rebuild the 000 circulators with just a cartridge. I don't believe you can do that with the 2400 series. I'm sure its no biggy. What a learning curve all this is!