With industry experience since 1856, A.Y. McDonald Mfg. Co. experts have compiled a number of frequently asked questions throughout the years. Before contacting us, feel free to visit this page to see if we can answer your question before you’ve even asked it.


What is your minimum order size?
No minimum order size required.

Can pressure rating on pressure relief valves (model 6214) be field adjusted?

Will A.Y. McDonald drop ship directly to my customer?
Yes, we will need the correct "ship to" address information. Provide this information by calling customer service at 1-800-292-2737.

Is there an extra fee for breaking carton quantities?

Who is my representative for A.Y. McDonald Mfg. Co.?
Please contact the factory at 1-800-292-2737 for this information.

What are A.Y. McDonald Mfg. Co. Product Lines?
A.Y. McDonald manufactures four different product groups:

Water Works Brass, Valves, and Fittings
Plumbing and Industrial Valves
Natural Gas Valves, Fittings, Accessories
Pumps and Accessories

What do the codes in the lower right corner of the Water Service product labels mean?
See this link for an explanation of Water Service product Label Coding.

How do I qualify for Free Freight?
For more information, review our Freight Program.

What standards do your high pressure gas valves comply with?
Our natural gas valves are designed and built to ASME B16.33.

What is the flow loss through A.Y. McDonald valves, fittings, or meter setters?
There are a number of factors that come into play including, but not limited to: friction, gravity, thermal effects, joints, length of pipe, size of pipe etc. Please contact customer service at 1-800-292-2737 with further details on your particular situation.

What's the difference between Brass and Bronze?
Brasses are copper alloys in which zinc is the principal alloying addition.
Bronze may also contain specified quantities of lead, tin, manganese and silicon.
The lower the zinc content in the copper-tin-(lead)-zinc alloys, the more copper-like, or "red" they appear.

After tightening our "Q" series compression assembly, I can still rotate the fitting on the tube, why?
This may be caused by one of two reasons.
1) The copper or PE tube is undersize. This instance requires the tube to be replaced.
2) The copper or PE is on the lower end of the tolerance. If this happens, the compression joint is designed to cover the entire range of diameters and will seal and have sufficient pull out strength to do the job.
Reasons why the tube rotates in our other compression systems may vary.

Do we have a compression fitting for PEX tubing?
Our T-series and -22 Mac-Pak CTS size compression ends will work with SDR 9 PEX tubing manufactured in accordance with ASTM f876/F877 and CSA B137.5. McDonald compression ends are for use with cold water applications only and a properly sized insert stiffener is required, i.e. McDonald 6131T or 6133T. Standard McDonald installation instructions should be followed.

What is the pressure rating of our fittings?
As long as connections are being used on the correct pipe or tube and assembled per our instructions, the fittings are rated to what ever the pipe or tube is rated for.

Can A.Y. McDonald fittings be used on CPVC tube?
Copper Tube Size (CTS) CPVC is typically used when the application calls for a higher temperature water than A.Y. McDonald fittings are rated for. Our CTS line of fittings will fit the CTS PVC - ASTM D2846/SDR II tube, however they should not be used where water temperatures will exceed 100°F.

Why are stab depths for plastic tube and/or pipe into compression fittings required?
1) To get enough length into the fitting to support the pipe or tube.
2) To make sure the pipe or tube is not inserted in too far as to prevent the insert stiffener from supporting the gripper of the compression nut.
3) To keep the pipe or tube from being inserted too far as to interfere with the operation of a valve or assembly.

What size are the lock wing holes in our ball valves?
Ball valves with 5/8" or 3/4" port balls have a 7/16" diameter hole. Ball valves with 1", 1 1/2", or 2" port balls have 1/2" diameter holes.

Can a UFR be used in conjunction with a PRV?
A UFR MAY be used with a PRV in the system as long as the PRV is before the meter and UFR such as in a tandem meter setting.
A UFR SHOULD NOT be used if the PRV is within 20 feet after the UFR. This will cause the UFR to not function properly.


Didn’t get the answer to your question? Visit our Contact Us page to connect with a member of our customer service team.