# CircuitSolver FAQ’s

Click on the question below to see the answer.

What is the GPM when the valve is closed?
When the CircuitSolver® valve is closed, it does not shut off entirely and still allows a fraction of a gallon per minute flow. This will enable it to better sample upstream water temperature changes and facilitate high temperature sanitizing cycles of the domestic hot water system. To determine the GPM, multiply the square root of the pressure differential across the valve by the Cv. For example, if the pressure differential is 4 PSI, the square root of 4 is 2, and 2 X Cv = GPM.

What is the full open flow rate of a CircuitSolver® valve?
The published Cv flow coefficient for each valve size allows calculation of the full open flow rate. Multiply the square root of the pressure differential across the valve by the Cv to get GPM. For example, if the pressure differential is 4 PSI, the square root of 4 is 2, and 2 X Cv = the full open GPM.

What is the highest temperature a CircuitSolver® valve can handle?
CircuitSolver® valves are rated to a maximum temperature of 250°F (121°C). All the valves can easily handle more than 212°F (100°C) which is the boiling point of water and is higher than any water temperature in a domestic hot water system.

Can CircuitSolver® valves be installed in any orientation?
Yes, the CircuitSolver will function properly in any orientation. However, valves with an integrated check valve must be installed with the flow arrow pointing in the correct direction.

Is CircuitSolver® certified to NSF 61 or Section 116875 of the California Health & Safety Code requirements?
Yes, the CircuitSolver® product line was tested by Truesdail, and they provided a report confirming that it is fully certified to both ANSI/NSF 61 and Section 116875 of the California Health & Safety Code California.

Is CircuitSolver® certified to the Massachusetts Board of Approval requirements?
Yes, all CircuitSolver® configurations have Massachusetts Board of Approval. Please click on the below links for approval information.
CircuitSolver® Approval

What warranty is offered with the valve? What is the life-cycle?
The CircuitSolver® product line offers a 3-year warranty. There have been tens of thousands of mixing valves used in domestic hot water systems for many years, and these mixing valves have the same type of actuator as CircuitSolver® valves. These mixing valves generally perform very well and have a proven history of reliability. Since a CircuitSolver® valve is all stainless steel, it can be expected to perform even better than these valves, which are generally brass.

I need to flush and sanitize my lines, will CircuitSolver® valves be able to handle the high temperatures?
Yes, all CircuitSolver® valves are rated to a maximum temperature of 250°F (121°C). All the valves can handle more than the highest water temperatures that will ever be encountered in domestic hot water systems.

My lines are prone to calcium buildup, will CircuitSolver® valves clog?
The actuator in CircuitSolver® is powerful enough to force out any buildup in its path when it modulates. The actuator develops over 40 lbs. (18kg) of thrust, which is more than enough to break loose any mineral buildup. It is also important to keep in mind that the mineral buildup is not very likely to occur in CircuitSolver® since it mostly occurs where there is a heating surface or a minimal leak.

Do I need to use a strainer with CircuitSolver® valves?
In general, No. Since the valves are used in potable water systems, particles in the water should already be taken care of. A strainer is recommended if there is a history of particulates causing problems in the domestic hot water system. We offer CircuitSolver® configurations pre-assembled with a strainer (CSUAS) for systems that need it.

What materials are used to produce CircuitSolver® valves?
CircuitSolver® valves are made entirely of Stainless Steel. Truesdail has tested the valves to confirm that they contain zero lead or other toxins and that they comply with the NSF 61 Section 8 Standard; Section 8 specifically applies to “Mechanical Devices such as filters, valves, pumps…”

How do you size CircuitSolver® valves for the recirculation system?
Since the flow through a CircuitSolver® only has to be enough to offset heat loss in piping, which is typically a very low flow, we recommend using valves that are the same size as the recirculation line.

How do you select the correct set-point for a CircuitSolver®?
As described in the product bulletin, the “XXX” in the model number is the desired return line temperature. For example, you want the return temperature to be 110°F, and the line size is 3/4″, you would select a CS-3/4-110.

How do you size the recirculation pump when using a CircuitSolver®?
Use the industry-standard plumbing engineering guidelines, for example, as shown in the ASHRAE handbook, to calculate system heat loss and system friction loss which will facilitate pump sizing. There is no need to oversize the pump to compensate for other factors.

What facilities have CircuitSolver® valves installed?
Please view our “Installations” page to see where CircuitSolver® is currently installed.

Do CircuitSolver® valves shut off tightly?
No, a small leakage (0.2 GPM) is built into the CircuitSolver® even when “closed.” This is done so the distribution branches are not totally dead-ended. Also, in some applications where the water distribution piping is occasionally chemically or thermally sterilized, the leakage allows enough of this flow through all parts of the system to accomplish the cleaning, regardless of temperature.

How do you recommend installing CircuitSolver® valves?
As shown in our installation and maintenance instructions, there should always be unions and shut-off valves installed before and after each CircuitSolver® valve. This provides more convenient access to the valve for future service. Since the water is almost always filtered/strained earlier in the loop, the addition of a strainer ahead of CircuitSolver® would be redundant. If no other strainer is present, consider installing one by each valve. See the Specifications & Installation Instructions page for more details.

How much does a CircuitSolver cost?
When factoring in the labor it takes to manually balance a system and the initial cost of balancing valves, CircuitSolver® provides significant savings over traditional methods. Contact a sales representative in your area for pricing and delivery.

When we install CircuitSolver®s, 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 - Douglas ORR Plumbing
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