WIKA 111.12 Back Mount Pressure Gauge for HVAC and Chilled Water

Overview

The WIKA 111.12 is the centre back mount version of WIKA’s model 111 copper alloy Bourdon tube pressure gauge, produced on modern automated lines in volumes of several million instruments per year. Because the connection leaves the case straight out of the back, the WIKA 111.12 is the natural choice wherever a gauge has to be read from the front of a panel, an air handling unit, a fan coil manifold or a chiller control board. WIKA lists heating and air-conditioning technology, pneumatics and medical engineering as the main application areas, and the gauge is designed per EN 837-1 or ASME B40.100.

Seven Star LLC supplies the WIKA 111.12 to HVAC contractors, district cooling operators, facility management companies and panel builders in Oman and across the GCC, holding offering engineering support in Muscat. Buyers searching for chilled water pressure gauges usually need dozens of identical instruments for pump sets, chillers and risers, and we can consolidate them into one consistent order with matching dials and connections.

How the Gauge Works

Inside the WIKA 111.12 a C-type or helical Bourdon tube in copper alloy deflects as system pressure rises. The deflection drives a copper alloy movement and a black plastic pointer (NS 40 to NS 100) across a white dial. As general background, copper alloy Bourdon gauges are well suited to clean water, glycol mixtures, compressed air and refrigerant-free HVAC media that will not attack copper alloy, and they are cost-effective where large quantities are installed.

The model has no case filling, so it is meant for locations without heavy pulsation or vibration, which describes most closed chilled water and heating circuits. For a vibrating pump skid, WIKA’s liquid-filled WIKA 213.53 is the better fit. The WIKA 111.12 can optionally be built with safety level S1 per EN 837-1 using a blow-out device, and with increased overload safety of 1.6 or 2 times, or a vacuum-resistant version to −1 bar, depending on the range.

Engineering Design of the WIKA 111.12

Cases are black plastic or black steel; WIKA notes that the NS 100 version of the WIKA 111.12 uses a black steel case. The window is crystal-clear plastic snap-fitted into the case. Available nominal sizes are 40, 50, 63, 80 and 100 mm (the 160 mm size exists only for the lower mount 111.10). Panel installation is handled with a panel mounting flange, a surface mounting flange for NS 63 and larger, or a triangular profile ring with mounting bracket for NS 80 and NS 100.

Process connections in copper alloy include G ⅛ B, G ¼ B and G ½ B per EN 837-1, ⅛ NPT, ¼ NPT and ½ NPT per ANSI B1.20.1, and R ⅛, R ¼ and R ½ per ISO 7, with ½ inch sizes reserved for NS 80 and NS 100. Optional restrictors of 0.5 mm or 0.3 mm damp pressure surges. Ingress protection of the back-mount WIKA 111.12 is IP41 for NS 40 to 63 and IP42 for NS 80 and NS 100, rising to IP44 with a steel case, so it is intended for indoor plant rooms and panels rather than exposed outdoor locations.

Key Features

The WIKA 111.12 brings these practical advantages to building services and light industrial projects.

• Centre back mount connection allows clean flush installation in control panels, chiller boards and equipment fascias.
• Five nominal sizes from 40 mm to 100 mm let designers match the gauge to panel cut-outs and viewing distance.
• Scale ranges reach 0–400 bar or 0–6,000 psi, with the low ranges typical of HVAC such as 0–4, 0–6 and 0–10 bar.
• Accuracy class 1.6 or 2.5 per EN 837-1, or grade B per ASME B40.100, is appropriate for monitoring and commissioning.
• Dial options include red mark pointers, an adjustable green sector for closed heating systems and a second scale in metres of water column.
• Certified to NSF/ANSI 61 G and NSF/ANSI 372 for drinking water system components.
• FM and UL approvals for fire protection systems are available for NS 100 with selected ranges and connections.
• A modular, high-volume design keeps unit cost low for projects that need hundreds of identical gauges.

Industrial Applications

In Oman the WIKA 111.12 typically appears on chiller and pump control panels in district cooling plants, on air handling units and fan coil manifolds in hotels, malls, hospitals and office towers in Muscat, and on booster sets and expansion vessels in residential compounds. Panel builders in Rusayl and Sohar use it on pneumatic control panels, and laboratories and clinics use it on compressed air and medical gas manifolds where a flush-mounted gauge is preferred.

For a complete chilled water monitoring point, engineers often pair the gauge with a bimetal thermometer such as the WIKA A52 Bimetal Thermometer, Back Mount, Stainless Steel Case on the same header, and with a Dwyer Magnehelic 2000 Differential Pressure Gauge across filters and coils for low differential pressure. When a lower mount version is needed for direct pipe installation, the companion WIKA 111.10 Bourdon Tube Pressure Gauge, Copper Alloy, Lower Mount uses the same measuring system. Seven Star LLC supplies the WIKA 111.12 with engineering support across Oman and the GCC, so maintenance contractors can replace failed gauges quickly without changing panel cut-outs.

Technical Specifications

The data for the WIKA 111.12 below is taken from WIKA data sheet PM 01.01, which covers both 111.10 and 111.12.

Sizing Tips for Chilled Water Systems

As general practice, select a range of roughly twice the normal working pressure so the pointer sits near mid-scale; a closed chilled water loop running at 4 bar is usually fitted with a 0–10 bar gauge. Add an isolating gauge cock so the WIKA 111.12 can be changed without draining the system, and keep the medium temperature within the −20 to +60 °C limit stated in the datasheet, which comfortably covers chilled water and most low temperature heating circuits.

How to Order

For a quotation on the WIKA 111.12, send Seven Star LLC your nominal size, scale range and unit, connection thread, case material and quantity per size. Our Muscat team will confirm availability and lead time, provide the WIKA data sheet PM 01.01 and support HVAC and chilled water projects throughout Oman and the GCC.