Rinnai, the UK leader in hot water systems, has recently completed an installation of 20 HDC 1500i units on shower blocks at an MoD barracks. LPG is the onsite fuel for all the Rinnai systems. Rinnai designed the systems in close co-operation with the local contractor who installed all the units – and the on-site facilities management company.
Rinnai continuous flow condensing units were specified based on previously completed projects on many army camps spread throughout the country

The end-user, the facilities provider and the installing contractor were all agreed on the excellence of Rinnai product performance, energy savings on fuel, product reliability & durability.
Comprehensive site surveys were completed between Rinnai and the services provider and designs for the systems were based on using two of what was the then plant rooms which housed two extremely large calorifiers. Each plant room was re-engineered with the installation of 10 high performance, high efficiency Rinnai HDC1500i (59.5kW) continuous flow, instantaneous water heaters per plant room.

Each plant room of 10 units were installed in ‘banks’ of five units and set with the Rinnai (MECS) Manifold Electronic Controls.  This intelligent energy optimising system brings additional water levels into operation only when required, meaning energy is only used when needed.

The MECS system also ensures system longevity as it ensures that each water heater in the bank is used for the same period of time over its life cycle guaranteeing unnecessary wear and even usage.

Each of the ‘banks’ of five units were also designed and supplied with a common header flue system which provides a compact, neat installation, as well as minimising plant room terminations and offering a quicker, easier installation and a more efficient maintenance programme.

Rinnai’s HDC1500, also known as the Infinity Plus Cascade, is an award-winning range of units. The range was developed to guarantee the maximum amount of affordable, ecologically friendly safe-temperature controlled hot water on demand at any one time by even the heaviest commercial user, even at peak times. In this case an army barracks. The Rinnai 1500i is engineered to the highest standard and is technologically advanced with a host of features giving added value.

Both Rinnai HDC1500 internal and external models turn in an impressive energy performance of 105% net efficiency. *Each Infinity Plus Cascade module comprises a minimum of two HDC1500 units and as any number of modules can be manifolded, the capacity for never ending ‘cascading’ hot water is infinite. Installation is straightforward and simple – each Rinnai HDC 1500i Infinity Plus Cascade comes with its own precision engineered rack, so there is no need to fabricate one or get involved with major re-jigging of pipe work or excessive flueing, the rack eliminates these time-consuming procedures, streamlining installation and helping keep remedial costs to a minimum.

The benefits for the end user are big savings on fuel over other forms of water heating solutions, with the added advantage that there is no need to give up valuable space to install a cylinder. And there are no standing losses to account for as occur with traditional stored hot water systems. The Rinnai system produces useable hot water on demand, at the turn of a tap or the push of a shower button. The relatively compact footprint of the units also means they can be housed in tight spaces and still be easily accessible for maintenance and servicing.

According to Chris Goggin: “Rinnai Infinity Plus 1500i Cascade represents the best value-for-money commercial hot water solution on the market today, delivered direct to site in one complete, easy to manage package. Its impressive energy performance ratings also make it a highly desirable development at a time when everybody is looking at decreasing energy bills and maximising energy efficiency.”

The Ministry of Defence (MOD) estate covers around 240,000 hectares. It has 45,000 buildings, including barracks, airfields, naval establishments, military training estate, workshops, offices, messes, family housing, 700 scheduled archaeological monuments and more than 170 ‘sites of special scientific interest’.

According to Chris Goggin, in charge of Operations: “Rinnai condensing continuous flow water heaters are low NoX, less than 50mg with gross efficiencies of 96-97% and recovery of 740 litres per hour at 50° Delta.  All our units are A rated on ErP.

The condensing process delivers 95% thermal efficiency, which translates to significant energy savings when compared to standard on-demand water heaters. Rinnai’s high efficiency condensing range of continuous flow water heaters, including the HDC1500 with its 96-97% gross efficiency, covers a vast number of requirements.

* In accordance with BS EN 677

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