A data centre is a cooling problem first and a heating problem second, but the second part is still your responsibility. The data hall may never need a radiator, yet the offices, plant rooms, battery rooms and welfare areas around it do, and the boiler plant serving them can fail in winter regardless of how well the servers are cooled. This article sets out the data centre heating cooling requirements that matter to facility managers in the North East: the temperature and humidity ranges to work to, how cooling is typically delivered, where boilers fit, and the gas safety duties that come with gas-fired plant.
We are a Gas Safe registered commercial heating contractor, not a cooling design service. Cooling design should be done by a qualified mechanical or M&E engineer. What follows is intended to help you understand who owns which plant and what questions to ask.
IT equipment converts almost all the electricity it draws into heat. In a populated data hall that output far exceeds what the room loses through walls, floor and roof, so the engineering effort goes into removing heat, not adding it. That is the source of a common misconception: servers heat the room, so no heating plant is needed.
That holds only for the equipment space, and only while the equipment is running at load. How much it matters depends on which of three building types you manage:
In each case there are spaces that rely on building heating. Offices and control rooms need comfortable conditions for staff. Plant rooms, stair cores and corridors need enough background heat to stay above the point where condensation forms. UPS and battery rooms usually have their own temperature requirements, and battery manufacturers specify operating ranges that you should follow.
A cold Northumberland winter adds a further risk. An unheated or under-heated space next to a warm, humid one can produce condensation on cold surfaces, and moisture near electrical equipment is a hazard in its own right. Heating in these areas is part of protecting the IT, not a separate comfort matter.
Start-up and recovery are the other cases. A hall that has been shut down, or a new fit-out that is not yet fully loaded, may have little internal heat to rely on, and the building's heating strategy has to cover that gap.
The most widely used reference for IT environments is the set of thermal guidelines published by ASHRAE Technical Committee 9.9. It defines recommended and allowable envelopes for temperature and moisture, grouped by equipment class. The recommended range is the band in which equipment is expected to run reliably over its life. The allowable ranges are wider and describe conditions equipment can tolerate for limited periods. The guidelines are revised periodically, so take exact figures from the current edition rather than from a summary, and treat any number quoted second-hand, including in articles like this, as something to verify. Your cooling designer should be working to a specific edition and class.
Measure at the server inlet, not the room average. A room can read a comfortable average while hot exhaust air recirculates to the top of a rack and pushes inlet temperatures well above target. Sensors placed at rack inlets, at several heights, show what the equipment actually experiences.
Too hot, and equipment can throttle its performance to protect itself, then shut down. Fan speeds rise and component life can shorten. Too dry, and the risk of electrostatic discharge increases. Too humid, and condensation or corrosion becomes possible, particularly on cold surfaces or where air is cooled below its dew point.
Also check the equipment manufacturers' own specifications and warranty conditions. These can be narrower or different from the general guidelines, and a warranty claim may depend on operating within them.
The right approach depends on the load and the building. Three broad options cover most sites.
Layout matters as much as equipment. In a hot aisle/cold aisle arrangement, racks face each other so that cold supply air enters from one aisle and hot exhaust leaves into the other. Containment, using doors, roofs or panels to physically close off either aisle, stops hot and cold air mixing. Without it, units work harder to hold the same inlet temperature, and gaps such as unused rack positions without blanking panels quietly undermine the design.
N+1 means the site has the number of units needed to meet the load (N) plus one spare, so a single failure or a planned service does not cause an overheating event. Higher levels duplicate whole systems. A site with no redundancy has a single cooling failure as a direct business continuity risk, and a hall can heat rapidly once cooling stops. Note that redundancy in IT, such as mirrored servers, does not mean redundancy in building services. Both need to be planned separately.
Free cooling uses cooler outside air, or cool water, to reject heat when conditions allow, reducing compressor running time. The North East's relatively mild climate can suit this for many hours of the year. Whether it works on a given site depends on the design, the humidity range you are targeting and the quality of the outside air, since filtration and contaminants such as coastal salt or industrial pollution need consideration. Treat it as a design question for your M&E engineer.
Cooling systems using refrigerants are also subject to F-gas rules, which change over time. As of now, confirm current requirements with your refrigeration or air conditioning contractor.
Boilers serve the building around the data hall. In most sites that means space heating for offices, control rooms and support areas, plus domestic hot water for welfare facilities. Some systems also use boiler-fed steam or hot water for humidification, though many sites use electric humidifiers instead. Do not assume which applies to you: confirm what the boiler plant actually feeds by checking the site's M&E design documents and as-built drawings.
That clarity matters for responsibility. In a multi-tenant or mixed-use building, the landlord or managing agent may own the boiler plant while a tenant owns the server room cooling. Knowing where the boundary sits tells you who must arrange maintenance, and who to call when something fails.
Servers produce a steady stream of low-grade heat, and in principle it can be recovered to feed heating circuits. The difficulty is temperature. Air leaving a data hall is typically too cool to heat a building directly through conventional radiators, so recovery usually involves heat exchangers and often heat pumps to lift the temperature to a useful level. This suits some sites better than others: it works best where there is a nearby, consistent heat demand and a load that is reliably high. For a small server room in an office, the economics and complexity may not justify it. If it interests you, ask a mechanical engineer to assess it as part of a wider design review, not as an add-on.
A boiler failure in December can leave a whole building cold even when the data hall is entirely unaffected. Staff areas become unusable, pipework in unheated spaces risks freezing, and condensation risk rises in cold zones. Plant condition therefore matters: age, service history, and the availability of key spares such as pumps, controls and ignition components. Knowing your lead times for critical parts before the heating season is far cheaper than discovering them during a breakdown.
All work on gas boilers, flues and gas pipework must be carried out by a Gas Safe registered engineer. That includes installation, repair, servicing and commissioning. There is no safe in-house or DIY route, whatever technical skills your team has in other areas. You can confirm any engineer's registration, and the types of gas work they are qualified for, on the Gas Safe Register, and you should ask to see their ID.
The Gas Safety (Installation and Use) Regulations 1998 require gas appliances, fittings and flues to be installed safely and maintained in a safe condition, by competent, registered people. For landlords, they also require an annual gas safety check of relevant appliances and flues and the keeping of records. As of now, the detail of who is a duty holder, and what falls within scope, depends on how the premises are let and used, so check your own position and take advice if you share a building with tenants or contractors.
The Health and Safety at Work Act 1974 sits alongside this. It places general duties on employers and those in control of premises to protect employees and others from risk, which in practice means maintaining plant properly, assessing the risks and having sound procedures.
Leave the area immediately. Do not operate light switches or electrical equipment, do not use naked flames, and open doors and windows on your way out if it is safe to do so. Then call the National Gas Emergency Service on 0800 111 999.
A building holding sensitive electronics needs this written down in advance. Staff should know that a suspected leak means evacuation first, and that nobody should return to check the IT. Your emergency plan should identify who calls the service, where the gas isolation point is, who is responsible for sign-off before re-entry, and how IT continuity is handled when people cannot be in the building.
Reliability comes from routine. For gas-fired heating plant, that means an annual inspection and service completed before the heating season begins, ideally by early autumn, so faults are found while there is time to fix them. A thorough visit covers more than the burner: pumps, controls, safety devices, flues and ventilation all deserve attention, as do water treatment and pressure, and any components that are near the end of their life.
Emergency planning is the second half. Keep a documented list of callout contacts, out-of-hours arrangements and site access procedures, including who holds keys and how an engineer gets past security to a plant room. Record your known single points of failure, such as a single boiler serving the whole building or a single pump with no standby. Commercial Boiler Solutions offers emergency callouts and same-day service across the region, including Newcastle, Sunderland, Middlesbrough, Tyneside, Wearside, Teesside and North Yorkshire, but a quick response works best when the engineer already knows your plant.
You can read about our commercial boiler services, see how our maintenance contracts work, or check our frequently asked questions.
Data centre heating cooling requirements split cleanly in two. Cooling, humidity and airflow in the hall belong with a qualified mechanical or M&E engineer. The heating that keeps the rest of the building safe, dry and usable belongs with a Gas Safe registered contractor who knows commercial plant.
The practical rule: know what your boiler plant feeds, know who owns it, and have it serviced before winter, not after the first fault. If you would like a Gas Safe registered inspection or a maintenance contract for your site, we can help.