Industrial heat pump maintenance and AMC
Tetra Heat Pump is a product of Promethean Energy Private Limited. We maintain industrial heat pumps under annual contract across India. Our published response window is 24 to 48 hours, and it does not depend on your location. An industrial heat pump needs its heat exchanger surfaces kept clean, its refrigerant charge checked, its compressor condition monitored and its water side managed. It needs no certificated attendant on shift and no statutory annual inspection, which is the largest difference between owning one and owning a boiler.
We set the service interval from your running hours, your duty and your site conditions. We do not sell it as a fixed number of visits.
What needs maintaining?
Seven items, and the first is where almost all of the lost performance goes. None of them announces itself as a fault, so a scheduled contract catches them and a call-out does not.
| Item | Why it matters |
|---|---|
| Heat exchanger surfaces | Scale and fouling reduce heat transfer. The first symptom is a slowly falling coefficient of performance, not a fault |
| Refrigerant charge and leak check | An undercharged circuit loses capacity before it trips, and a leak is a cost and an environmental exposure |
| Compressor oil and running condition | Oil condition, vibration and current draw are the early indicators on the most expensive component in the machine |
| Water side: strainers, treatment and flow | Indian borewell hardness and dissolved solids vary widely, and the water side is where most performance is lost |
| Air side, on air source units | Dust loading on the coil and fan condition, which on an industrial site change with the season |
| Controls, sensors and setpoints | A drifted sensor or an overridden setpoint costs more energy than most mechanical faults, and nothing alarms |
| Electrical connections and power factor | Loose terminations and a deteriorating power factor both reach the bill before they reach a failure |
How often should it be serviced?
Service it at an interval set against the machine's maintenance schedule and your site. A unit running continuously on a dusty site with hard water needs attention more often. A unit on two shifts, on a treated closed loop indoors, needs it less.
Four things set the interval, and a supplier should be able to say how each one moves it:
- 1 Running hours. A continuous duty and a seasonal one are different machines by the end of year two.
- 2 Water quality on the source and sink sides. Test it at design, and do not assume it. It drives the exchanger cleaning interval more than anything else.
- 3 Site conditions. Dust loading, ambient temperature and salt air on a coastal site all shorten it.
- 4 What an hour of downtime costs your line. This decides which tier is worth buying, and it is a number only you have.
Maintenance programmes
The three tiers differ on coverage and on visit frequency. The response window is the same on all three.
Essential
Scheduled maintenance
- Scheduled visits, at an interval set against your running hours and site conditions
- Inspection to the maintenance schedule, with a written report
- Performance readings taken and logged at every visit
- Telephone support during business hours
- Published response window of 24 to 48 hours
Professional
Maintenance with remote monitoring
- Everything in Essential, at a higher visit frequency
- Remote monitoring and diagnostics through the controls interface
- Performance trended between visits as well as at them
- Telephone and remote support outside business hours
- Published response window of 24 to 48 hours
Enterprise
Maintenance, parts and site cover
- Everything in Professional, at the highest visit frequency
- Parts and labour coverage defined in the contract schedule
- A named engineer and a defined escalation route
- Spares held against your unit configuration
- Published response window of 24 to 48 hours
What is checked at a scheduled visit
Mechanical
- Compressor operation and vibration
- Heat exchanger condition
- Expansion valve function
- Fan motors and bearings
- Pump operation and seals
- Piping and insulation integrity
Electrical
- Electrical connection tightness
- Control panel inspection
- Sensor calibration
- Safety switch testing
- Variable frequency drive operation
- Earthing verification
Refrigerant and fluids
- Refrigerant charge level
- Leak detection scan
- Oil level and condition
- Water quality testing
- Filter condition
- Pressure readings
What drives the AMC cost?
An AMC price depends on the installation, so a single figure would be wrong for most readers. Here is what moves it, so you can tell whether a quotation is priced against your installation or against a template.
What raises it
- Higher visit frequency, set by running hours and site conditions
- Parts and labour brought inside the contract
- Spares held against your configuration
- Remote monitoring and performance trending between visits
- Unit count and configuration, since a multi-unit project is more to inspect
What is chargeable outside the contract
- Consumables and parts, where the tier does not include them
- Work arising from water quality outside the design basis
- Damage from an event outside normal operation
- Changes requested to setpoints, controls or integration scope
Ask any supplier which of those lines sit inside the quoted figure and which do not. A contract where that boundary is unstated is where the disagreements happen in year two.
How does it compare with maintaining a boiler?
The mechanical maintenance is comparable. The statutory burden is not, and that is where the ownership difference sits. A hot water circuit below 100°C is not a registered boiler under the Indian Boiler Regulations.
| Obligation | Registered boiler | Heat pump below 100°C |
|---|---|---|
| Certificated operator on shift | Required on a registered boiler, on every shift, with relief cover | Not required. The machine runs unattended under its controls |
| Relief cover rules | A person in charge may be relieved only twice a day, for a combined two hours, and only by a first-class certificate holder | Not applicable |
| Statutory annual inspection | The certificate runs one year, re-inspection after expiry is mandatory, and the plant shuts down for it | None below 100°C. Maintenance is scheduled around your production |
| Long-term inspection | Decennial bare inspection at ten years, and working-pressure derating on shell types beyond twenty-five | Not applicable |
| Fuel handling and storage | Fuel deliveries, storage, ash handling on solid fuel, and the labour for all of it | None. The fuel is electricity |
| Routine maintenance | Water treatment, blowdown, trap survey, burner service, tube cleaning | Exchanger cleaning, refrigerant check, compressor condition, water and air side, controls |
One condition applies to that table. The obligation attaches to the registered boiler, whatever load it carries. If you keep a boiler for the duties that need steam, you also keep the attendant and the annual inspection. The full treatment of the threshold is here.
What degrades performance on an Indian site?
None of these five causes trips an alarm. A machine losing a tenth of its efficiency looks exactly like a machine that is working.
| Cause | What it does | How it is controlled |
|---|---|---|
| Scale and fouling on exchanger surfaces | A falling coefficient of performance that nobody notices, because nothing fails | Water tested at design, pre-treatment sized for the actual supply, and a cleaning interval that is followed |
| Coil corrosion on coastal sites | Lost capacity, and eventually a leak on an outdoor coil | Coil metallurgy and coating specified at design for Goa, Kochi, Chennai and Mumbai sites |
| Dust loading on air source coils | Reduced airflow and a smaller effective source, worst in the dry season | A cleaning interval set against the site's dust load, and fin spacing chosen for it |
| Setpoint drift and manual overrides | The machine delivering hotter than the process needs, at a lower COP | Setpoints reviewed at every visit against what the process actually requires |
| Source stream changes | A source that was warm at commissioning cools when the upstream process changes, and the lift grows | Source temperature trended, and reviewed whenever the plant changes |
How is performance verified?
We verify it by measuring the coefficient of performance at the duty. That takes three readings at the same moment: heat delivered, electricity consumed, and the source and output temperatures the machine is working across.
Heat delivered comes from the flow rate and the temperature difference across the condenser. So the installation needs a flow meter and matched temperature sensors on the circuit. Electricity consumed comes from a dedicated meter on the unit, not from the plant's main incomer. Neither is expensive at installation and both are awkward to add afterwards, so they belong in the specification.
Ask for those three readings at every scheduled visit, logged and trended. A falling COP is the earliest signal this equipment gives, and it is visible only against a baseline taken at commissioning.
Remote monitoring takes the same readings continuously. The unit connects to BMS, SCADA and PLC networks over Modbus and BACnet, so the data sits in the system your shift engineer already watches. The integration page explains how it connects.
Before you sign a service contract
Service and reliability in India
What actually fails on this equipment, and the questions to put to a supplier before the order.
The specification
The temperature envelope, capacity per unit and per project, and the operating points behind the COP.
The equipment
Configurations, what each one suits, and which duties are inside the range and which are not.
Tell us the installation and we will quote the contract
Send the unit configuration, the running hours, your water test and what an hour of downtime costs the line. Those four are what a contract should be priced against.