Getting the right mix
High performance, service and reassurance are just as important as the price tag, says Heatrae Sadia
According to MODUS (The Association of Manufacturers of Domestic Unvented Systems), sales of unvented systems have been increasing by approximately 15% each year since 2000. As demand for unvented hot water storage continues to grow in the UK, so does the total number of cylinders available. With so many manufacturers entering the fray, offering models designed for use in domestic, commercial and public sector applications how are specification decisions to be made?
According to Heatrae Sadia, manufacturer of Megaflo HE, the UK’s leading unvented water heating cylinder, a number of factors should be taken into consideration. Here, David Webster, Marketing Manager at Heatrae Sadia, offers some advice and explains why the principles of whole-life costing should be applied when choosing a hot water cylinder.
Unvented hot water cylinders are now widely regarded as the preferred water heating solution in the domestic residential market. But it isn’t only homeowners who are warming to the benefits of unvented storage systems. Consider commercial and public sector premises such as hotels, sports and leisure centres, care and nursing homes, hospitals and prisons, who all have a requirement for instant hot water – and an unvented hot water cylinder provides the ideal solution.
Yet, with demand grows choice and installers and specifiers can now choose from models differing significantly, in terms of construction, conditions of the guarantee and the quality of the support package offered by the manufacturer. The key to the specification decision is finding the optimum combination of whole-life cost and quality to meet the end user’s requirement, and not simply opting for a particular model on purchase costs alone. So, where do you begin?
Perhaps the most important place to start when looking at whole-life costs is the material from which cylinders are made. Since unvented cylinders store water under pressure, it is vital that they are extremely strong, durable and corrosion resistant. In the UK, they are generally made from stainless steel, copper or glass lined mild steel. As in so many other high-tech industries today, high grade stainless steel is fast becoming a preferred material; and in terms of unvented hot water cylinders, Heatrae Sadia took the first pioneering leap over a decade ago.
The term ‘stainless’ has been adopted as a generic name for a wide range of steels that are corrosion or oxidation resistant. Unvented cylinders constructed from high grade, corrosion resistant stainless steel do not require a protective interior coating or sacrificial anode. Cylinders manufactured from mild steel, on the other hand, require a coating or glass lining and an anode to make them corrosion resistant. Some lower grade stainless steels may also require an anode. These anodes must be inspected for signs of corrosion each year and will often need to be replaced.
Of course, cylinders manufactured from mild steel or low grade stainless steel will initially cost less than those in high grade stainless steel, so they might seem more attractive. However, they will require ongoing service, regular maintenance and possible replacement after a relatively short life, whereas high grade stainless steel cylinders require little maintenance or repair and have proven longevity. Mild steel glass lined cylinders are also around 50% heavier than an equivalent stainless steel unit, and are therefore more difficult to manoeuvre and install.
So, we’ve considered how the cylinder is made and the impact on its likely lifespan and maintenance requirements. It’s also critical to consider functional performance. Whatever type of project you are working on, your client will want a steady, fast flowing and uninterrupted supply of hot water, so you will need to consider hot water recovery rates. Look for models that exceed CheSS Best Practice for heat recovery and insulation; after all, customers will be disappointed if they have invested in a new hot water system and they are unable to use taps simultaneously or if the hot water runs out after a couple of showers.
Guarantees are another important consideration. Look carefully at the terms and conditions. For example – do their guarantees cover on-site parts and labour? Can they be transferred to new owners if the premises are sold? Our 25-year guarantees really are fully comprehensive and offer reassurance on both counts.
Finally, consider the level of support you will receive from the manufacturer. Customer service is of paramount importance to Heatrae Sadia. We offer nationwide technical and service support and will provide advice, assistance and product guidance whenever required. We are also pleased to be able to offer a free and fully indemnified design service.
Our cylinders have always had a reputation for high quality, durability and trouble free operation. The Megaflo HE, our large unvented cylinder, is our best selling product. Manufactured from Duplex stainless steel, Megaflo HE has a high resistance to stress corrosion cracking, fatigue, erosion and chloride ion attack. Other characteristics of Duplex include high tensile and yield strengths, low thermal expansion, high heat conductivity and high energy absorption.
For longer life, each Megaflo HE cylinder undergoes comprehensive post-weld treatments. Not all manufacturers carry out this important process, called pickling, which is vital in ensuring that a cylinder retains a high corrosion resistance. We recently invested £6 million in our welding and pickling facilities, and we believe that no other manufacturer can match our production technology.
We offer a 25 year guarantee on Megaflo HE, which provides everyone in the supply chain with confidence. Other manufacturers may appear to match this, but our guarantee on Megaflo HE includes on site parts and labour, and can be transferred if the property is sold.
We know only too well that that when selecting an unvented water cylinder, initial purchase costs will always play a big part in the decision. However, I would urge you to take the long view. Look beyond the price tag and opt for a quality, fit and forget, high grade stainless steel unvented water cylinder, with a lengthy and comprehensive guarantee and good manufacturer support. Anything less is likely to be a false economy in the long run.