---
product_id: 6544877
title: "Dwyer® Liquid Filled Wall Mount Manometer, Mark II 25, 0-3\" w.c., 3% Accuracy"
brand: "dwyer"
price: "KD 59.30"
currency: KWD
in_stock: true
reviews_count: 8
category: "Dwyer"
url: https://www.desertcart.com.kw/products/6544877-dwyer-liquid-filled-wall-mount-manometer-mark-ii-25-0
store_origin: KW
region: Kuwait
---

# 0-3 inH2O measuring range freeze-proof red gauge fluid 3% accuracy precision Dwyer® Liquid Filled Wall Mount Manometer, Mark II 25, 0-3" w.c., 3% Accuracy

**Brand:** dwyer
**Price:** KD 59.30
**Availability:** ✅ In Stock

## Summary

> 📊 Elevate your HVAC game with lab-grade precision and never miss a pressure drop again!

## Quick Answers

- **What is this?** Dwyer® Liquid Filled Wall Mount Manometer, Mark II 25, 0-3" w.c., 3% Accuracy by dwyer
- **How much does it cost?** KD 59.30 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.com.kw](https://www.desertcart.com.kw/products/6544877-dwyer-liquid-filled-wall-mount-manometer-mark-ii-25-0)

## Best For

- dwyer enthusiasts

## Why This Product

- Trusted dwyer brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Built to Endure:** Freeze-proof, low-evaporation fluid and leakproof O-ring seals ensure durability in harsh environments.
- • **Precision You Can Trust:** Achieve ±3% full-scale accuracy for reliable pressure readings every time.
- • **Expanded Scale for Clarity:** Inclined-vertical design with red gauge fluid enhances resolution for easy, precise monitoring.
- • **Cost-Saving Filter Monitoring:** Visualize air filter performance to extend filter life and avoid costly premature replacements.
- • **Effortless Installation & Leveling:** Mount on any vertical surface with built-in spirit level for perfect alignment in minutes.

## Overview

The Dwyer® Mark II 25 Liquid Filled Wall Mount Manometer offers a 0-3 inH2O measuring range with ±3% accuracy, featuring freeze-proof red gauge fluid for enhanced readability and durability. Designed for easy vertical mounting with a built-in spirit level, it provides precise differential pressure monitoring ideal for HVAC filter performance and air velocity applications. Leakproof seals and an overflow tank minimize fluid loss, making it a reliable, cost-saving tool for professionals seeking accurate, long-term pressure measurement.

## Description

The Dwyer Mark II 25 inclined differential manometer with red gauge fluid has a 0 to 3 inH2O measuring range, built in zero level and molded plastic case for monitoring air velocity and air filter performance, and taking pressure measurements above and below atmospheric pressure. Red gauge fluid is freeze-proof and has lower evaporation rate for use in cold environments, and produces expanded scale viewing for improved reading resolution. The built-in zero level provides linear calibration. The manometer has a styrene-acrylonitrile housing, indicating tube, and fluid wells for strength and durability. The molded ABS knobs and zero adjust plunger and shock-mounted glass level vial are wear-resistant. Leakproof O-ring seals and overflow tank reduce the risk of fluid loss. Scales are lithograph printed on aluminum to ease reading, and are epoxy coated to protect against wear. The manometer can be mounted on any vertical surface. SpecificationsPressure typesSingle and differentialMedia typeAirCase materialStyrene-acrylonitrileMeasuring range0 to 3 inH2OFluid typeRed gauge fluid, 0.826 sp. gr.MountStand and vertical mountAccuracy+ or - 3% full scaleMaximum pressure10 psi/70 kPaMaximum temperature140 degrees F/60 degrees CWeight1.04 lbs./472gDimensions5-29/32 x 7-13/32 x 2-1/4 inches (H x W x D)H is height, the vertical distance from the lowest to highest point; W is width, the horizontal distance from left to right; D is depth, the horizontal distance from front to back.Manometers measure the pressure of a liquid or gas. They are used in laboratory, medical equipment, engineering, automotive, and heating, ventilation, and air-conditioning applications. Manometers measure any combination of gauge, absolute, or differential pressures. Gauge pressure is the amount of pressure in a system relative to the ambient pressure, absolute pressure is the amount of pressure in a system relative to an absolute vacuum, and differential pressure is the difference between two pressures. Analog manometers are composed of columns of liquid, and they use gravity and the liquid's density to calculate pressure. Because they have no moving parts, analog manometers do not require re-calibration. Digital manometers have pressure sensors that are connected to a system with a hose to provide a digital readout of the amount of pressure present in a system. They use microprocessors to calculate pressure, and they require periodic calibration to help ensure accuracy.Dwyer Instruments manufactures measurement and control instruments, including pressure gauges, flow meters, level instrumentation, temperature instrumentation, and air quality monitors. The company, founded in 1931, is headquartered in Michigan City, IN. What's in the Box?Mark II 25 manometerRed gauge fluid, 1oz.Flexible double column plastic tubing, 8 ft.(2) Tubing connectors, 1/8"(2) Mounting screwsRed and green pointer flagsInstructions

Review: $60 and 20 minutes saves a lot of expensive filters - With increasing combinations of heat and smoke in our area, we upgraded our air handler to accomodate a MERV16 4" filter. The filters are about $100 each and the default suggested lifespan is one year. It needed about 20 mintues to install this manometer and discover that at one year of age our filter was causing pressure drop far below the rating of our air handler. Given that interception by filters improves as they choke, the filter is doing fine. A six month extension of filter life in our case pays for half the cost of this device. Photo indicates simplicity of installation. Two holes in ductwork for tubing port attachment, double-sided tape to mount manometer. Note that the area marked "filter" on the air handler is superseded by the larger filter housing at right (it's important to make sure manometer tubing is correctly installed on upstream downstream sides of filter).
Review: Outstanding product and more like a piece of lab equipment. - I am using this Manometer to allow for a visual identification of when my whole house furnace filter needs to be changed. As the filters are between $30 and $40 I do not want to change too often as I will be wasting money and if I wait too long potentially damaging my HVAC system which is less than ideal..... My current scheme is to pull the filter out and look at the color of the filter which is inaccurate to say the least, so after a recent cold snap and my furnace not operating due to a filter that needed to be changed I opted to do something about it. Competitive products seemed a little cheap to me so I went this route. As a mechanical engineer by training I was very pleased with the lab instrument quality of this Manometer, when you open yours up you will be surprised by the size of the this unit, fully 6"x6" or more. Everything that I needed to accurately measure a pressure differential was included as well as a surprise built in level for that really assisted with the installation of the product. What is extremely important about this Manometer is that the first inch of the water column is essentially more "horizontal" allowing for more accuracy in the first inch of the water column. The reason for this is that your furnace is most likely designed for about 0.5" of static external pressure. This is typically found on the HVAC systems label. So in my case when I installed the Manometer and zeroed it out with no filter in place, then added a new clean filter it measured .1" rise in the water column. That is about 20% of the total rise allowed by my HVAC units spec. (By the way that was a dead on match to the Filtrete specs for this filter, which is always nice) So I will need to change that filter when the water column reads .5" of water. Having that first inch essentially expanded out is really nice so I can see what is going on visually. Long story short, if this keeps my wife happy because her house is warm as her furnace filter was changed when it should have been then all things considered this was a great purchase. :-) Have a great day and some fun as a home geek. Jeff

## Features

- Leakproof O-ring seals and overflow tank reduces risk of fluid loss
- Can be mounted on any vertical surface and built-in spirit level simplifies leveling
- Inclined-vertical manometer for use in air velocity and air filter performance applications, and other general purpose applications
- Red gauge fluid is freeze-proof and has lower evaporation rate for use in cold environments, and produces expanded scale viewing for improved reading resolution

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B009PAN3C8 |
| Best Sellers Rank | #81,701 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #30 in Manometers |
| Date First Available | February 17, 2007 |
| Is Discontinued By Manufacturer | No |
| Item Weight | 10.4 ounces |
| Item model number | 25 |
| Manufacturer | Dwyer Instruments |
| National Stock Number | 6685-00-897-4402 |
| Product Dimensions | 7.5 x 1.25 x 6 inches |

## Images

![Dwyer® Liquid Filled Wall Mount Manometer, Mark II 25, 0-3" w.c., 3% Accuracy - Image 1](https://m.media-amazon.com/images/I/61IMLzTTDNS.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ $60 and 20 minutes saves a lot of expensive filters
*by D***M on January 16, 2024*

With increasing combinations of heat and smoke in our area, we upgraded our air handler to accomodate a MERV16 4" filter. The filters are about $100 each and the default suggested lifespan is one year. It needed about 20 mintues to install this manometer and discover that at one year of age our filter was causing pressure drop far below the rating of our air handler. Given that interception by filters improves as they choke, the filter is doing fine. A six month extension of filter life in our case pays for half the cost of this device. Photo indicates simplicity of installation. Two holes in ductwork for tubing port attachment, double-sided tape to mount manometer. Note that the area marked "filter" on the air handler is superseded by the larger filter housing at right (it's important to make sure manometer tubing is correctly installed on upstream downstream sides of filter).

### ⭐⭐⭐⭐⭐ Outstanding product and more like a piece of lab equipment.
*by J***Y on January 17, 2017*

I am using this Manometer to allow for a visual identification of when my whole house furnace filter needs to be changed. As the filters are between $30 and $40 I do not want to change too often as I will be wasting money and if I wait too long potentially damaging my HVAC system which is less than ideal..... My current scheme is to pull the filter out and look at the color of the filter which is inaccurate to say the least, so after a recent cold snap and my furnace not operating due to a filter that needed to be changed I opted to do something about it. Competitive products seemed a little cheap to me so I went this route. As a mechanical engineer by training I was very pleased with the lab instrument quality of this Manometer, when you open yours up you will be surprised by the size of the this unit, fully 6"x6" or more. Everything that I needed to accurately measure a pressure differential was included as well as a surprise built in level for that really assisted with the installation of the product. What is extremely important about this Manometer is that the first inch of the water column is essentially more "horizontal" allowing for more accuracy in the first inch of the water column. The reason for this is that your furnace is most likely designed for about 0.5" of static external pressure. This is typically found on the HVAC systems label. So in my case when I installed the Manometer and zeroed it out with no filter in place, then added a new clean filter it measured .1" rise in the water column. That is about 20% of the total rise allowed by my HVAC units spec. (By the way that was a dead on match to the Filtrete specs for this filter, which is always nice) So I will need to change that filter when the water column reads .5" of water. Having that first inch essentially expanded out is really nice so I can see what is going on visually. Long story short, if this keeps my wife happy because her house is warm as her furnace filter was changed when it should have been then all things considered this was a great purchase. :-) Have a great day and some fun as a home geek. Jeff

### ⭐⭐⭐⭐⭐ Back in business
*by H***D on November 3, 2024*

Last week I noticed that our radon fan had stopped running. Who knows, maybe it was 6 months ago that it stopped. It's not something we regularly check on. Anyhow, since I had to replace the fan, I did a full check of our system, which is 25+ years old. I found this Dwyer manometer in the rafters, and the fluid was empty. Since the fluid alone is $25, and the probability was that there was a leak somewhere, I figured it was best to just replace it. I installed the fan earlier today, and when the manometer showed up, it only took about 10 minutes to fill, and calibrate per the instructions. A few minutes later, after screwing in to the existing holes, everything was working.

## Frequently Bought Together

- Dwyer® Liquid Filled Wall Mount Manometer, Mark II 25, 0-3" w.c., 3% Accuracy
- Dwyer® Red Gage Fluid, A-101, 1 oz Bottle, .826 Specific Gravity
- Fieldpiece ASP2 Static Pressure Probes

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.com.kw/products/6544877-dwyer-liquid-filled-wall-mount-manometer-mark-ii-25-0](https://www.desertcart.com.kw/products/6544877-dwyer-liquid-filled-wall-mount-manometer-mark-ii-25-0)

---

*Product available on Desertcart Kuwait*
*Store origin: KW*
*Last updated: 2026-02-25*