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MUELLER Sight Glass: Sweat, Copper, 7 7/8 in Lg - Sweat Connection Sight Glasses
MUELLERSweat Connection Sight Glasses

MUELLER Sight Glass: Sweat, Copper, 7 7/8 in Lg

The MUELLER A 18123 is a sweat connection sight glass made of copper, measuring 7 7/8 inches in length with a 5.2-inch cut-out length. This MUELLER-branded component is designed for visual flow indication in copper…

SKU 3G-OTH-71921

Also listed as: A18123 · A-18123

Brand
MUELLER
Item
Sight Glass: Sweat, Copper, 7 7/8 in Lg
Category
Sweat Connection Sight Glasses
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Technical Specifications

MUELLER
Manufacturer Part Number
A 18123
Material
Copper

Technical Documents

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MUELLER Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The MUELLER A 18123 is a sweat connection sight glass made of copper, measuring 7 7/8 inches in length with a 5.2-inch cut-out length. This MUELLER-branded component is designed for visual flow indication in copper piping systems.

Frequently Asked Questions

What is the MUELLER A 18123 sight glass used for?

The MUELLER A 18123 sight glass is used for visual flow indication in copper piping systems. It allows operators to observe fluid movement, color, and clarity without opening the line, making it essential for monitoring in HVAC, refrigeration, and industrial process applications.

What are the specifications of the MUELLER A 18123 sight glass?

The MUELLER A 18123 is a sweat connection sight glass made of copper. It has a length of 7 7/8 inches and a cut-out length of 5.2 inches. The manufacturer part number is A 18123. It is designed for sweat (solder) installation into copper piping systems.

Where to buy the MUELLER A 18123 sight glass worldwide?

3G Electric supplies the MUELLER A 18123 sight glass worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on this MUELLER component.

How to install a MUELLER sweat connection sight glass?

To install the MUELLER A 18123, clean and flux the copper pipe ends and the sight glass connections. Heat the joint evenly and apply solder until it flows fully around the connection. Allow to cool naturally. Ensure the sight glass is oriented for clear flow visibility before soldering.

Used in

Common applications for MUELLER
Commercial refrigeration systems — Mueller steel shell filter driers for moisture and contaminant removal in liquid lines.
HVAC installations — Mueller sweat connection ball valves for flow control in refrigerant circuits.
Industrial process cooling — Mueller magnetic check valves to prevent backflow in refrigerant piping.
Refrigeration system maintenance — Mueller flare nuts and bushings for access valve connections.
Low-GWP refrigerant systems — Mueller A2L-compatible ball valves for use with low-flammability refrigerants.
Retrofit projects — Mueller filter driers and valves for upgrading existing refrigeration equipment.

MUELLER Products

3G Electric supplies MUELLER sweat connection sight glasses. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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