We manage and operate a Rental Division from our HQ here in Andover that specializes in the long term rental of Standby and Base Load running diesel generators.

Generator sizes range from 10kVA to 2MVA or greater if required with options for parallel or standby operation.

We have a nationwide network of generators and supports structures that enable us to respond rapidly to your power requirements.

All generators of whatever size are delivered and installed by fully factory trained engineers.

Scheduled servicing is included within any Generator rental contract and includes all consumable parts, lubricating oil and coolant.

Each set is covered by a Merlin 24/7 service and maintenance package that is included in the price.

The Generator is a small part of the overall solution, cable kits, bunded fuel tanks, AMF panels, distribution panels, security locks, low voltage transformers, earth rods etc are all available as optional extras to ensure you get a complete system individually tailored to your application

Installing and Generators For Sale

Long term rental periods can range from a few weeks, many months or even years.

For customers with long term or semi permanent power requirements, we undertake a full site survey to ensure the optimum choice of Generator, control panel, fuel system and distribution cabling.

Regular on site service and maintenance with 24/7 technical support are included in all of our Rental contracts.


  • Optional extras

    A wide range of optional extras are available direct from our Depot.

 These include:

  • Cable Kits
  • Distribution boards
  • Bulk Fuel tanks
  • AMF Panels
  • Earthing kits
  • Low voltage transformers
  • Splitter boxes
Installing and Generators For Sale

Generator Loadbanking Testing

Extended and regular full load testing of standby diesel Generators and other power systems using a variable loadbank is essential to ensure reliable and consistent performance during mains supply failures.

Generator in particular benefit as testing removes carbon deposits from pistons and exhaust systems which can build up over time through running the system a less than the design load.


Generator Loadbanking Testing

Generator Refuelling

Refuelling contracts are available to holders of a Powercare or Maxicare Plus service contracts.

For a fixed annual fee Merlin will routinely deliver diesel directly to the Generator fuel tank, you only pay for the fuel delivered. (Note there is a minimum charge of 200 litres/delivery). Fuel is charged at the rate prevailing at the time of delivery.

A fleet of specialist 4x4 vehicles cover the country drawing fuel from oil depots, customers resources, or Merlins own fuel stores around the UK mainland


Generator Refuelling

Fuel Polishing

Fuel polishing will prevent any build up of sludge in the filters, prevent water entering the Generator (and reducing the power output) and generally ensuring a more reliable standby power system

Fuel Polishing

Air Conditioning Systems

Supported by all leading manufacturers Celtaire has an innovative and practical approach to the design, installation and maintenance of the full spectrum of air quality equipment.

Providing planned preventative maintenance for all the equipment it supplies across the UK, Celtaire offers extended warranties and 24/7 fast response service to all market sectors. Risk Assessments and Method Statements are provided to ensure fully compliant aftersales care.

Air Conditioning Systems

Split Systems

Probably the most popular of the small to mid range commercial systems, these comprise a wall or floor mounted external condenser unit (s) with internal fan coil unit(s). These are typically of the flush ceiling type where a suspended ceiling is fitted but wall mounted or ‘under ceiling’ units have their advantages for particular applications.

Celtaire’s experienced survey engineers will advise you on the most efficient and cost effective solution for your requirement.

All units also act as highly efficient eco-friendly heatpumps.

Split Systems

Chilled Water Systems

These systems are typically installed in high capacity applications such as data centres, hospitals and supermarkets.

Using chilled water as a cooling medium rather than a refrigerant gas these systems require a different maintenance regime to others.

Celtaire work closely with the leading manufacturers to formulate the best, most innovative design solutions

Chilled Water Systems

Absorption Cooling

Where a ready supply of hot water is available (such as sites with Combined Heat and Power (CHP) Systems) very cost effective use of the hot water can be made with and Absorption Cooling System.

Celtaire are heavily involved with these state of the art systems currently developing such a solution for a major leisure centre in the South as part of an overall energy package.

Mobile, Temporary and Disaster Recovery Systems.

Increasing activity in the temporary cooling and disaster recovery market has involved Celtaire in numerous projects both planned and unplanned.

As part of shentongroup the culture and resources are there to manage your requirement in the most efficient way.

Mobile, Temporary and Disaster Recovery Systems.

Solar Energy

Power solutions company, shentongroup, has announced the introduction of a new range of solar energy solutions. The range is being sold to both industrial and commercial customers who, as part of their company's environmental policy in addressing climate change, wish to be 'seen to be green'.

Combined Heat and Power System

Scorpion Power Systems, a specialist supplier of power generation and energy support systems, supplies powertherm, an innovative and cost effective range of Combined Heat & Power(CHP) systems that reduce energy costs and increase power reliability and quality. Unique to the European market, powertherm's engine technology gives 85.5% package efficiency with thermal recovery, enabling the units to provide an outstanding energy output compared to fuel consumption as well as shrink a company's carbon footprint.

Combined Heat and Power System
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