Balancing DHWS Return with CircuitSolver®
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The Trouble In The Return
In periods of no use, domestic hot water recirculation systems (DHWS) act as a closed-loop. The mixing valve will utilize the water from only the return line and water heater since no additional cold water can enter the system.
If too much return flow is directed to the water heater, the water temperature throughout the system will gradually increase until it matches the storage tank temperature. Inversely, if too much return flow is directed to the mixing valve, the temperature throughout the system will drop to ambient temperature.
Conventionally the way to solve this issue is by installing a manual balancing valve between the water heater and the return flow into the water heater in a DHWS. The flow requirement set is a “guesstimate” and cannot automatically adjust with the changing dynamics of a recirculating hot water system. This results in a temperature creep up or down over time.
A better approach is using a thermostatic valve, CircuitSolver®, instead of the manual balancing valve. The CircuitSolver® set-point should equal the desired return temperature. When installed on the supply inlet of the return piping to the water heater (see diagram below), CircuitSolver® will flow water back to the water heater in proportion to how cool the return water temperature is relative to the mixing valve output temperature.
When the water temperature at the return valve equals the desired return temperature, the CircuitSolver® would be closed, except for a small bypass, providing minimal flow back to the water heater. As the return water temperature falls below the desired temperature, the CircuitSolver® will open, providing increased flow to the water heater, effectively minimizing both positive and negative temperature creep.
This temperature device addresses a temperature problem and will ensure no significant temperature creep, either higher or lower than the mixing valve output temperature.
The master mixing valve output temperature is 125°F with a desired return temperature of 115°F, 10°F ∆T. The set-point of the CircuitSolver® in the return line to the water heater should be the same as the CircuitSolver valves at the end of each branch/riser.
How To Select The Correct CircuitSolver®:
The master mixing valve output temperature is 125°F with a desired return temperature of 115°F, 10°F ∆T.
The set-point of the CircuitSolver® in the return line to the water heater should be the same as the CircuitSolver valves at the end of each branch/riser.
I would tell any contractor, building engineer, and mechanical engineer if you are looking at CircuitSolver®, it is simple, it is easy to use, and it works right from the get-go. Chris Watts Plumbing Service Manager at Braconier in Denver, CO
I try to have CircuitSolver® specified on as many jobs as possible due to the simplicity of it. Eric McTee Plumbing Designer at ME Engineering in Golden, CO
When we install CircuitSolver® valves, it corrects the client’s hot water circulation problems, and everything operates as it’s designed. We are going to keep installing them. Jason Putnam Project Manager at Douglas ORR Plumbing in Miami Springs, FL
We’ve used CircuitSolver®s exclusively now for several years in every application we can. Simply stated, the product is easy to install and works very well with no issues to date. Christopher Meurer Plumbing Operations Manager at J.C. Cannistraro, LLC in Boston, MA
CircuitSolver® makes balancing the system so easy. We don’t have to manually set each line or make any adjustments. We have had absolutely no balancing issues since we started up the system. Richard Parker Plumbing Contractor at Pan-Pacific Mechanical in Fountain Valley, CA
USC Villages Student Housing - By using CircuitSolver®valves, we saved time and money by not having to balance the system or make any adjustments. It made the process much easier and smoother. Richard Parker Plumbing Contractor at Pan-Pacific Mechanical in Fountain Valley, CA
Simply stated, CircuitSolver® valves are easy to install and work very well with no issues to date. They’re efficient and take the time typically required to manually balance systems at the end of the project out of the equation. Christopher Meurer Plumbing Operations Manager at J.C. Cannistraro, LLC in Boston, MA
CircuitSolver® was able to automatically balance the system when engineers could not. Mark Wilmink MarkCo Plumbing in Florence, KY
CircuitSolver® valves are efficient and take the time typically required to manually balance systems at the end of the project out of the equation. We have started up systems in the afternoon to come in the next morning to find hot water perfectly balanced throughout all risers and zones. Christopher Meurer Plumbing Operations Manager at J.C. Cannistraro, LLC in Boston, MA
What an awesome little device these guys make. It’s a no-brainer. Andy Crossland Principal Mechanical Engineer at Crossland Engineering LLC in Honolulu, HI
Rittenhouse Hill Apartments - We had a very complicated apartment restoration involving 47 risers. CircuitSolver® saved a lot of time, installed easily, used smaller recirculation pumps to save energy & wear, and continues performing well. Ron Miller President at Adelphia Plumbing in Philadelphia, PA
I haven’t come across another product like CircuitSolver®. Once you install the valves you never have to adjust them, unlike manual balancing valves where you have to balance every single valve you install. Richard Parker Plumbing Contractor at Pan-Pacific Mechanical in Fountain Valley, CA
The University of South Florida - On startup of this install, the system automatically balanced itself in under 3 hours, all without manual labor thanks to CircuitSolver®. The plumbers actually went out a did another job, went to breakfast, and when they came back, the system was balanced. Mike Bishop V.P. of Engineering at RGD Consulting Engineers in Jupiter, FL
Right after the installation the general manager went around the building and there was a noticeable difference with quick delivery of hot water. Andy Crossland Principal Mechanical Engineer at Crossland Engineering LLC in Honolulu, HI
The Da Vinci Project - By using CircuitSolver® balancing valves, we were able to save both time and money. The start-up process was much faster by not having to manually adjust each valve. After installation, the system balanced itself and required no maintenance. Arturo Hernandez GJM Engineering in Los Angeles, CA
It usually takes 2-3 plumbers, 2-3 days to balance a system of this size, but by using CircuitSolver® this process was done instantly. Huge savings in terms of time and effort typically devoted to the balancing process. Stephan Thompson Plumbing Contractor at E.M. Duggan Inc. in Canton, MA
CircuitSolver® is a great product. The valves automatically adjust to changing temperatures and pressure drops unlike manual and automatic balancing valves. Plumbing Contractor Production Plus Plumbing in Vista, CA
The advantages of the system are an efficiently balanced system, saving time testing and balancing the system, lower utility bills and reduced water usage. Luke Holding Project Engineer at The Beck Group in Dallas, TX
Using CircuitSolver® makes balancing the system so easy. The valves automatically adjust themselves, so you don’t have to check each valve once installed, and there are never any callbacks for issues. Arturo Hernandez GJM Engineering in Los Angeles, CA
CircuitSolver® makes the initial startup so easy. When we turned it on, the valves balanced the whole system without us having to make any adjustments. We never have any issues when installing them in our projects. Plumbing Contractor Production Plus Plumbing in Vista, CA
By eliminating the conventional method of using fixed flow balancing valves and installing CircuitSolver® valves instead we were able to resolve our lack of hot water in some sectors of the hospital issue instantly. André Renaud Building Consultant at Mental Health University Institute of Quebec
CircuitSolver® is a game changer in balancing DHWS and I would definitely use it as a standard in future projects. Matt Trevino Plumbing Engineer at DBR Engineering in San Antonio, TX
CircuitSolver®, being that it is an automatic balancing valve, just makes the job of balancing an intricate hot water system that much easier. David Texter Plumbing Engineer at Browne Engineering in Cincinnati, OH
It was taking over a minute and a half to get hot water, and now it’s down to 15-20 seconds…also a huge conservation of water…it was a fairly simply retrofit. Robert Albanese Owners Representative for The Austonian in Austin, TX
Before CircuitSolver®, we would have wait times between 5-7 minutes for hot water on the higher floors. Since we have installed CircuitSolver® valves, we are getting hot water when we need it and have not had a single complaint. Robert Schrieber Maintenance Manager at Embassy Suites in Brunswick, GA