To get email notification when someone adds to a thread you're following, click on the star in the thread's header and it will turn yellow; click again to turn it off. To edit your profile, click on the gear.
The Wall has a powerful search engine that will go all the way back to 2002. Use "quotation marks" around multiple-word searches. RIGHT-CLICK on the results and choose Open Link In New Window so you'll be able to get back to your results. Happy searching!
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
The right system circulator with a Viessmann WB2B 35
I have a Mono Flo single main system designed in the mid 50's that I am installing a WB2B 35 into. The original system has a 2" main that splits into two 1 1/4" branch mains. The branches are currently zoned with B&G 100 circulators installed on the returns which then tee back to a 2" return main. The branches are balanced with a pair of gate valves with thermometers located in front of The circulators.
The Viessmann is designed not to have zones and I do not need them. I am reworking my near boiler piping to Viessmanns System layout 2 using the Viessmann low loss header and recommended Grundfos boiler and DHW circulators. I am planing to do away with the B&G's and use a single system circulator on the 2" main supply.
My question concerns the system circulator. I have a calculated head loss of 4.8 ft and flow of 8.2 gpm @ a 25 deg delta. I am interested in using a Taco Bumblebee to maintain a constant delta t across the reset curve. My concerns are weather I should use a delta t circulator and with the varying flow will I be able to balance the system by throttling the existing gate valves or should I do it another way?
I have about 1800 sq ft of emitters with a design heat loss of about 109,000 BTUH so I only need about 125 deg for a design temp. We only hit the design temp here a few days a year so if I can hit a delta T of 25 Deg I should be condensing almost all of the time. I really don't care about anything beyond consistent comfort and economy so what ever circulator I need to do that with will be fine. I was just thinking that a variable speed pump would likely give me a nice consistent room temp across the reset curve. I have put a lot into calculating my head loss so I hope it is correct. Compensating for head loss is another atractive advantage of the Bumblebee. I also think it is cool that it displays the current flow.
As usual I would appreciate any thoughts you guys have and I do not mind learning I am wrong. That is how I got this far.