Tnermostat Q's

Tim Potter

Hi, I am progressing on my Heating system upgrades.



I have in-floor radiant that I have split up from 4 large zones into 10 zone loops, utilizing a Rehau Pro-Balance Manifild with 4 wire actuators. I added outdoor reset injection off of an 80 Gal Boiler Buddy. My boiler (Slant-Fin Sentry SX-150) is GROSSLY over-sized for the heat load, but does just great making a ton of hot water for showers in the 80 Gal Boiler-Mate. I presently have 4 zones controlled by the Honeywell round t-stat's,  BUT I only have 2 wires between existing t-stat & zone valves. It does not look easy to add or change wires in my house, because of the finished lower level. I need to add a few t-stats because of splitting up some large zones. I would like all t-stats to match for ease of operation.



I am considering:

(1) Wirsbo/Uponor WT1, Litrature states it is designed for radiant, runs on 2 wires, and can be set up with differential or pulse-width modulation. seems to be reasonably priced, say "X"

(2) Wirsbo 501s (includes sensor), for the existing 4 runs, mounting t-stat in the boiler room and utilizing the existing 2 wires to mount the sensor remotly in the room needing control. Not having the actual t-stat control in the room seems to be a negitive. I would then add the 501 (no sensor) for the additional runs that I can make with 4 wire cable, and those would actually be in the room. This product seems to be purpose built by Tekmar, also designed for radiant, and has cycles per hour control that can auto-learn the zone. Price is 2x for the 501, and 3x for the 501s compaired to the WT1

(3) Tekmar 507, 508,(sensor capible) & 509, (508+079 sensor). Not sure what the difference between the Tekmar product, and the Wirsbo Product is, anyone wish to weigh in ???? The price is 1.25x 507, 1.5x 508, & 2x 509 compaired to the WT1.

 

I know not to discuss price, My price comparisons are just for relitive merit of higher priced units vs lower priced units taking into consideration additional features. I hope this passes muster with the group.

 

Thank You in advance for any input.



Tim

tim dot potter at ymail dot com - if you wish.