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MUELLER A 18123 Sweat Connection Sight Glass - Sweat Connection Sight Glasses
MUELLERSweat Connection Sight Glasses

MUELLER A 18123 Sweat Connection Sight Glass

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
A 18123 Sweat Connection Sight Glass
Category
Sweat Connection Sight Glasses
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

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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Compatible alternatives & equivalents

Cross-referenced by specification & description
This brass sight glass features sweat connections for copper pipe installation, allowing visual inspection of fluid flow in piping systems. It is commonly used in HVAC, refrigeration, and industrial process lines to monitor liquid or gas movement, detect bubbles, or verify system charge without disassembly
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This brass sight glass features sweat connections for copper pipe installation, allowing visual inspection of fluid flow in piping systems. It is commonly used in HVAC, refrigeration, and industrial process lines to monitor liquid or gas movement, detect bubbles, or verify system charge without disassembly
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This sight glass features a flared swivel connection for easy alignment in piping systems. Constructed of brass, it allows visual monitoring of fluid flow, color, and clarity. Commonly used in HVAC, refrigeration, and process lines
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This sight glass features a flared swivel connection for easy alignment in piping systems. Constructed of brass, it provides visual flow monitoring to observe fluid movement and detect blockages. Suitable for use in HVAC, refrigeration, and process lines
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This sight glass features a flared swivel connection and is constructed from brass. It is used for visual flow monitoring in industrial piping systems, allowing operators to confirm fluid presence and clarity in applications such as lubrication, cooling, and process lines
This flared swivel connection sight glass is constructed of brass for visual fluid monitoring in piping systems. The swivel design facilitates alignment during installation, allowing observation of flow, clarity, or liquid presence in lines
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This flared swivel connection sight glass is constructed of brass for visual fluid monitoring in piping systems. The swivel design facilitates alignment during installation, allowing observation of flow, clarity, or liquid presence in lines
This MUELLER sight glass features a brass construction with flare connections for visual flow monitoring in piping systems. It allows operators to observe fluid movement, detect blockages, or verify system operation in refrigeration, HVAC, and process lines
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This MUELLER sight glass features a brass construction with flare connections for visual flow monitoring in piping systems. It allows operators to observe fluid movement, detect blockages, or verify system operation in refrigeration, HVAC, and process lines

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Copper sight glass with sweat connections for permanent installation in copper piping systems. Overall length 7-7/8 inches, cut-out length 5.95 inches. Allows visual monitoring of fluid flow to detect blockages or confirm circulation in HVAC, refrigeration, and plumbing lines
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