WINTER READY?

November is here already and what a year it’s been, for us at Automatic Schematic we have just announced our second ever online event and today is the release of our 12th article. As usual we take a slightly controversial approach asking questions that many do not want to ask, pushing the boundaries of compliance. We see this as a way to improve the water industry, create valuable discussion and increase awareness on a variety of topics within the hot and cold water department.

Winter officially begins in just 51 days in the United Kingdom on the 21st December, but are you winter ready? Preparing early is always the best course of action. What even is being winter ready, what can be forgotten and what steps need to be taken going into the colder months of the year.

Although all types of buildings are designed for a variety of purposes the core remains the same. Shelter for rest, work or leisure. Management and maintenance structures are designed to increase the longevity of a buildings life span in the hope of reduced repair damage without the need for replacing parts internal and external of the building. Due diligence such as temperature monitoring is not often carried out in residential buildings, however, in commercial and industrial buildings such tasks are mandatory.

Legislation states that hot water should be stored at 60 ºC with the immediate flow pipework also distributing at 60 ºC, this is to allow for a drop in temperature as water travels through the pipework to reach the outlet at a minimum of 50 ºC (unless preset with a mixer, see part two on thermostatic mixer valves for more details), all return and related circulating pipework should remain above 50 ºC throughout the system (The 60/50 rule).

Again I am going to use the word leniency in this article for a very specific purpose, legionella bacteria thrives between 25 – 45 ºC with an optimum temperature of 37 ºC, the bacteria cannot however survive for extended periods of time between 80 – 124 minutes at only 50 ºC. As we increase the temperature to 60 ºC it will survive for only two minutes, hence the 60/50 flow and return rule. When we increase the temperature further to 70 ºC the bacteria will die almost instantly, this is actually a method of disinfection without using chemicals called pasteurization, some cylinders have a built in mechanism where they will automatically increase for one hour throughout the day to a minimum of 60 - 70 ºC.

Because of legionella bacteria’s kill zone temperature range it does allow for a hot water cylinder to actually be preset at 50 – 60 ºC, and I say this with EXTREME CAUTION! Personally, I would set a MINIMUM of 55 ºC only with increased temperature monitoring to weekly or fortnightly instead of monthly. Please note I only give this advice as an increased energy efficiency technique and any recommendations in risk assessments should remain strictly in line with legislation and guidance as the safe and proper method. The responsible person should be adequately training in legionella management and competent to carry out such works.

(Below is an example of colonised Legionella Pneumophila bacteria)

During winter and indeed throughout the year this leniency may not be possible due to a number of factors, if the hot water asset, be it cylinder, calorifier or water heater is not operating correctly it will actually require a preset temperature of higher than 60 ºC, as we know these assets can be more prone to faults during winter. Another factor is incorrectly/poorly insulated pipework, when hot water is distributing through long lengths of pipework there can be significant heat loss, plant and boiler rooms can also drop to a very low ambient temperature with them often found on the outside of a building with louvered doors. Remember Automatic Schematic is hosting a two day online event about hot water assets January 2nd - 3rd which you won’t want to miss, more details can be found on our company page over the next couple of months.

Servicing should be carried out on the buildings main hot water asset on an annual basis, so why not schedule it in at winter time, this is the flip side to cold water storage tanks where tank inspections are mandatory during summer, take a look at ‘Summer Tank Inspections’ which can also be found on our page. This winter cylinder servicing is possibly something that will be updated in HSG 274 Part 2 Table 2.1 at some point in the future and is only a new suggestion.

Being ‘winter ready’ is not only about hot water, the cold water system can be easily forgotten and pipework freezing is very common during cold winters, great for keeping legionella bacteria dormant but not great for system damage. Some building occupants will even shut off the water supply to prevent long term damage depending on the buildings use, there are other methods while keeping the water system online to counter this, such as, partially open valves to prevent freezing or increased water circulation. I have not heard of any instances or personally come across any situations where the cold water storage tank has frozen, but, again I’m sure in the right conditions tanks installed on an open roof space combined with an exceptionally cold winter it is not unheard of. 

As you know we currently only post articles about hot and cold water systems and making sure your home or work premises is winter safe will also include heating systems, building infrastructure both internal and external, energy supply and other servicing or maintenance. I have included some additional articles at the end of this one which give a number of helpful tips to keeping your building ‘winter safe’ not just relating to hot and cold water systems.

Thanks for reading and I hope you enjoyed this month’s article, next month we have another exciting Christmas announcement for business owners. To read similar topic’s on hot and cold water systems visit our website, company page or author's profile. If you have any suggestions on topics post them in the comments section below. Don't forget to FOLLOW OUR COMPANY PAGE, like, share and comment on this article!! 

If you or your company want to participate in our upcoming online event send all relevant information and material to our administration email at admin@automaticschematic.co.uk.

Below is an article which discusses a variety of topics on ensuring your home is winter ready.

Here is another article which gives 8 easy tips.