Description
A Hundred Litres.
This Is a Building-Services Decision, Not a Shopping One.
The largest storage geyser in the Monza Nu range, for homes where hot water demand is genuinely heavy · 100 litres stored · BEE 5-star rated · a Feroglas-coated heavy-duty steel tank and an Incoloy glass-coated element, both built for hard water · Whirlflow technology keeping incoming cold from mixing into the hot · 0.8 MPa (8 bar) rated pressure for high-rise supply · ELCB protection, an adjustable thermostat from 25 to 75°C, a thermal cut-off and a multi-function safety valve · IPX4 · a rust and shock-proof ABS body · vertical wall mount · 7 year tank, 4 year element, 2 year body warranty
100 kg
of waterthe part nobody plans for
This is the single most important thing to understand before buying a 100 litre geyser, and it is the thing most often overlooked. Water weighs a kilogram per litre. A hundred litre tank therefore hangs a hundred kilograms of water on your wall, plus the weight of the steel tank, the insulation and the casing around it. That is a structural load, not a fixture load. It needs a solid masonry or concrete wall, mounting brackets rated for the filled weight, and fixings chosen for that wall — and it categorically must not go on a drywall partition, a hollow block wall, or a false wall built to hide plumbing. The fixings that held a 15 or 25 litre geyser are nowhere near adequate. Have a competent person look at the intended wall before you order rather than after the unit arrives, and factor in that a filled tank must be drained before it can ever be taken down.
7 / 4 / 2 years — the split matters more the bigger the tank
The warranty here is divided exactly along the lines on which a geyser actually fails. Seven years on the tank, four on the heating element, two on the body and electrical components. Those are not arbitrary numbers. The tank and the element are the two parts hard water destroys, and they are the two that cost real money to replace — and on a hundred litre unit a perforated tank means replacing the largest appliance in the house, plus whatever the leak damaged on its way down. A manufacturer putting seven years behind a tank of this size is making a claim about its Feroglas coating that it has to honour. Compare that against anything else you are considering, because plenty of geysers quote one headline warranty figure that turns out to cover only the casing. Ask for the split in writing rather than a single number.
25–75°C adjustable — on this size, the setting is worth real money
Most people set a geyser to maximum and leave it there, and on a hundred litre tank that habit is expensive. Water stored hotter loses more heat to the room while it sits, and here you are paying to hold a hundred litres at that temperature around the clock — which gives away much of what a 5-star rating earns you. It also scales faster: mineral deposition from hard water accelerates sharply at higher temperatures, and scale on the element is what makes an old geyser slow before it finally fails. And at 75°C you mix in a great deal of cold at the tap anyway, so you paid to heat water you never used at that temperature. Set it to a moderate level that gives comfortable water with little mixing. Less electricity, slower scaling and a lower scalding risk — which matters with children or elderly parents in the house.
🎯 Suited to
This is a lot of geyser. For a single family bathroom, a 25 or 35 litre costs considerably less to buy, less to run, and asks far less of the wall. Tell us how many bathrooms it feeds and how many people use them, and we will size it honestly rather than sell you the biggest one.
An earth leakage breaker that trips if current finds a path it should not. On a high-load mains appliance in a wet room, this is a safety specification worth having.
A coated element resists scale far better than a bare one, which is why the element here carries four years rather than the usual two.
Stops incoming cold water mixing straight into the heated water above, so more of the stored 100 litres comes out genuinely hot rather than lukewarm.
The outer shell will not rust in a permanently humid bathroom the way a painted metal casing eventually does.
| Brand / Model | Havells Monza Nu — GHWAMUSWH100 ✅ |
| Type | Storage water heater (geyser), vertical wall mount ✅ |
| Capacity | 100 litres ✅ |
| Energy Rating | BEE 5-star ✅ |
| Inner Tank | Feroglas-coated heavy-duty steel ✅ |
| Heating Element | Incoloy, glass coated ✅ |
| Flow Technology | Whirlflow ✅ |
| Rated Pressure | 0.8 MPa (8 bar) ✅ |
| Thermostat | Adjustable knob, 25°C to 75°C ✅ |
| Safety | ELCB protection · thermal cut-off · multi-function safety valve ✅ |
| Ingress Protection | IPX4 — splash proof ✅ |
| Outer Body | ABS, rust and shock proof ✅ |
| Voltage | 230 V, 50 Hz AC ✅ |
| In the Box | Water heater · multi-function safety valve · 2 flexible pipes · 2 fasteners · user manual ✅ |
| Tank Warranty | 7 years ✅ |
| Heating Element Warranty | 4 years ✅ |
| Body & Electrical Warranty | 2 years ✅ |
| Wattage | ⚠️ Stated as 3000 W in supplier material, while Havells' specification tables for smaller models in this range state 2000 W. Please have us confirm against the rating plate before electrical work, as it determines the circuit and MCB rating. |
| Dimensions | ⚠️ Listed as 38.5 × 36 × 62.5 cm, which is smaller than the 50 litre unit in the same range and cannot be correct for double the capacity. Please have us confirm the actual dimensions before planning the installation. |
| Weight | Not stated — critical for wall fixings at this capacity; ask us ⚠️ |
| Heating Time | Stated as approximately 20 minutes; on a 100 litre tank this is unlikely for a full heat from cold and should be treated as indicative only ⚠️ |
| Standing Loss | Not stated in supplier material ⚠️ |
| Anode Rod | Not stated for this model ⚠️ |
Why buy from Mahajan Electronics?
- Genuine Havells with full brand warranty
- We size the geyser to the site and the household
- GST invoice — save up to 18% on business purchases
- 24-hour delivery across Delhi NCR
- 45+ years of trust · rated 4.7 on Google
- Raja Garden · Jail Road · Dabri Mor
Get the wall checked before you order this one.
Havells Monza Nu · GHWAMUSWH100 · 100 Litre Storage Water Heater · BEE 5-Star · Feroglas-Coated Heavy-Duty Steel Tank · Incoloy Glass-Coated Element · Whirlflow · 0.8 MPa (8 Bar) · ELCB · Adjustable Thermostat 25–75°C · Thermal Cut-Off · Multi-Function Safety Valve · IPX4 · ABS Body · 230 V · Vertical Wall Mount · 7 Year Tank · 4 Year Element · 2 Year Body
Warranty as per Havells India's terms and conditions — 7 years on the tank, 4 years on the heating element and 2 years on the body and electrical components. The scope of cover, parts and labour, exclusions, installation requirements, product registration and the service process are subject to brand policy and the final invoice or warranty card, and should be confirmed in writing before purchase. Warranty cover is generally conditional on correct installation by a qualified professional and on the appliance being operated within its rated pressure and supply conditions; damage arising from hard water, scale build-up, incorrect supply voltage, excessive supply pressure, dry operation, inadequate mounting, or unauthorised installation or servicing is commonly excluded. Descaling and periodic servicing are the owner's responsibility and may be required to maintain tank warranty validity. Supplier material for this model states the wattage as 3000 W while Havells' specification tables for smaller models in this range state 2000 W; the actual rating must be confirmed against the unit's rating plate before electrical work is carried out, as it determines the circuit and MCB rating required. The dimensions stated in supplier material, 38.5 × 36 × 62.5 cm, are smaller than those published for the 50 litre model in the same range and are inconsistent with a 100 litre capacity; actual dimensions must be confirmed before installation is planned. Weight is not stated and must be confirmed, as it is critical to the selection of mounting hardware. The stated heating time of approximately 20 minutes is indicative only, is unlikely to represent a full heat from cold at this capacity, and depends on the actual wattage, inlet water temperature, thermostat setting, water hardness, scale condition and ambient temperature. Hot water availability, temperature and electricity consumption vary with the same factors together with usage pattern, draw-off rate, pipe length and insulation, and maintenance. Stated capacity is the tank's storage volume; the quantity of usable hot water at a given temperature will differ depending on mixing at the outlet. Standing loss and the presence of an anode rod are not stated in supplier material. The BEE star rating is certified under standard test conditions and is not a guarantee of consumption in any particular installation; star ratings are as certified at the time of manufacture and subject to periodic revision. Explanations of mounting load, warranty structure, capacity sizing, thermostat setting and scaling provided here are general information to aid understanding and are not manufacturer specifications. This appliance must be installed by a qualified electrician and plumber on a correctly rated, properly earthed dedicated electrical point with an appropriate MCB; the ELCB is a protective device and does not remove the requirement for correct earthing of the installation. The multi-function safety valve must not be blocked, adjusted or removed. IPX4 denotes splash resistance only and does not permit direct water spray or immersion. The appliance must be mounted on a structurally sound masonry or concrete wall using mounting hardware and fixings rated for the filled weight, which at this capacity includes approximately 100 kg of water in addition to the appliance's own weight; it must not be installed on drywall, partition, hollow block or false walls, and fixings used for a smaller water heater will not be adequate. The site should be assessed by a competent person before ordering. The appliance must never be switched on with an empty or partially filled tank. Stored water may reach 75°C, a temperature capable of causing scalding; the thermostat should be set appropriately and particular care taken with children, elderly and vulnerable persons. The unit is rated for a maximum working pressure of 0.8 MPa; where supply pressure may exceed this, a pressure reducing valve is required and is chargeable separately. The appliance must be isolated and fully drained before any servicing or removal, and operation discontinued and service arranged if leakage, electrical tripping, discoloured water or unusual noise occurs. Installation, plumbing, electrical work, MCB, extended piping, pressure reducing valve, wall strengthening and any civil work are chargeable separately unless expressly included on the final invoice. Mahajan Electronics accepts no liability for damage or injury arising from incorrect or inadequate installation or from use contrary to the manufacturer's instructions. Image for reference only; actual serial number, manufacturing date, capacity variant, packaging, fittings, accessories and finish may vary by batch — confirm the model code and capacity against the unit's rating plate at the time of purchase.
Please Note: The image shown is for reference purposes only. Actual product details, including the serial number and manufacturing date, may vary.
