GMS

Grays Mechanical & Maintenance Services are a family run group set in the heart of Buckinghamshire
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GMS is a family run business set in the heart of Buckinghamshire, South of England. With a wealth of over 20 years experience in the industry, we operate as an independent supplier to offer impartial advice and guidance on the best equipment and leading technology, creating the perfect building environment to suit your needs.

28/10/2026

Three rooms, and not one of them straightforward

Most of the air conditioning you see online goes into new builds. Square rooms, flat ceilings, a convenient outside wall. Those jobs are lovely and they take a day.

This one was an older cottage, and it is a much better illustration of what we actually do.

The loft bedroom. Sloping ceilings on both sides and a velux in the pitch, which leaves almost no full-height wall. The unit went on the small triangle of gable above the stud wall - high, central, and angled so it throws air down the length of the room rather than straight into a slope two feet away. Get that wrong and you have a unit that cools one corner.

No gravity anywhere. Condensate normally runs downhill to a drain. In this building there was no fall available from any of the three unit positions, so every indoor unit is on a condensate pump concealed in trunking. Three rooms, three pumps, and no visible plumbing in any of them. It is more work and it is the right answer; the wrong answer is putting the unit somewhere convenient and leaving the customer with a box on the wall.

The outdoor unit went on the flat roof, which keeps it off the garden elevation entirely and away from anywhere anyone sits.

The finished job looks simple. That is what you are paying for - all three rooms heat as well as cool, each on its own control, and nothing on show that does not need to be.

If your house is old, awkward, listed, or just stubborn, that is not a reason it cannot be done. It is a reason to have someone look at it properly first.

Free, no-obligation home survey - call 01628 522802.

26/10/2026

The room everyone forgets ⚡

We finished a three-room installation in Bushey last week. Living room, bedroom and home office, all served by one outdoor unit at the side of the house, with twenty metres of pipework linking them.

The living room and the bedroom are the usual suspects. The office is the interesting one.

If you work from home, you already know the problem. The study or the spare bedroom is almost always the worst room in the house: one window, often facing the wrong way, a door that stays shut, and a computer quietly putting out heat all day. By two o'clock in July it is several degrees warmer than anywhere else, and a desk fan just moves the warm air around.

People leave that room until last because air conditioning in an office feels like a luxury. We would argue the opposite. It is the room you spend most of your waking hours in, and the one where being uncomfortable actually costs you something.

A few things worth knowing about a job like this:
• One outdoor unit can serve several rooms - here it is four ports, three used, so there is capacity left if a fourth room is ever added
• Each room sets its own temperature, so the office can run cool all day while the bedroom does nothing until the evening
• Every unit heats as well as cools, which in an office means a warm room in January without putting the whole house heating on for one person
• It is all controlled from an app, so you can start the office cooling before you walk into it

Commissioned, tested and handed over the same day.

Free, no-obligation home survey - call 01628 522802.

24/10/2026

Who is air conditioning actually for? 🏡

If you judged it by the advertising, you would think the answer was new builds and loft conversions. Open-plan kitchens, home offices, houses that have just had a hundred thousand pounds spent on them.

Here is the answer we see on the ground, and it is not that.

Some of the most worthwhile systems we fit go into ordinary homes that have been lived in for decades, for people who find the summer harder than they used to. Heat is genuinely difficult as you get older. Sleep goes first, and everything else follows it. A bedroom that holds 20 degrees through a hot night is not an indulgence - it is the difference between coping with a heatwave and dreading one.

This week we were in Bushey doing exactly that. A 3.5 kW unit in the lounge and a 2.0 kW in the bedroom, each on its own control so the rooms can run completely differently. The lounge needed a concealed condensate pump because there was no natural fall from where the unit had to go - the sort of thing you work out on the survey so that nothing has to be boxed in or chased out afterwards.

Both units heat as well as cool, so the house is warmer in February and cooler in July, from the same kit. 🌡️

If you have a parent or a relative who struggles in the heat, it is worth a conversation. We will come and look, tell you honestly what a room needs, and there is no charge for that.

Free, no-obligation home survey - call 01628 522802.

23/10/2026

The question we get asked more than any other 👀

"Where does all the pipework go?"

It comes up on nearly every survey, usually within the first minute. And it is a fair question, because most people have seen one bad installation - white plastic trunking marching diagonally across the front of a house or none at all! And assume that is what they are signing up for.

So here is a real example, finished in Beaconsfield this week.

The outdoor unit went at the side of the house, on wall brackets so it sits clear of the ground and the border planting. From there the refrigerant pipes run in black trunking along the underside of the flat roof coping, turn one corner, and drop straight down to the unit. Black against brick, following a line the building already had.

Inside, you would not know any of it was there. A 3.5kW wall unit in the lounge, sitting above the picture rail. A 2.0kW in the bedroom above the mirror. No boxing, no visible pipe in either room, nothing chased into a wall that did not need it.

Both rooms run from that one outdoor unit and set their own temperatures independently, so the bedroom can be cool overnight while the lounge does something completely different.

The part worth taking away: the route is decided at survey stage, standing in the garden working out which line the eye already follows. It is not worked out on the morning of the install. If the installer looking at your house cannot tell you exactly where the pipes will run before they start, that is worth asking about.

Free, no-obligation home survey - call 01628 522802.

21/10/2026

Tuesday, Wooburn Green. 🌧️

It started raining at about half nine and did not stop. Three of our engineers spent the day in a side passage with no roof over any of them, running twelve metres of pipework between a living room, a bedroom and a single outdoor unit.
They got absolutely soaked. The system went in anyway, commissioned and handed over the same day.

Worth knowing if you are thinking about it: equipment lead times across our industry are the longest we have known them. Ringing round in the middle of a heatwave does not get you a system in that heatwave - it gets you a place in a queue.

Autumn is when you get ahead of that. And because these systems heat as well as cool, you will be using it this winter rather than waiting until June to find out whether it was worth it.

Free no-obligation home survey - call 01628 522802.
uk

19/10/2026

You do not need a renovation to put air conditioning in ❄️

Most of the photos we share are new extensions and finished builds, because those are the ones that appear the best. But the job we do most often is this one: an ordinary house, already lived in, no scaffolding and nothing being pulled apart.

This week it was a home in Marlow. The dining room and a bedroom both needed doing, so rather than two separate systems we fitted one outdoor unit at the side of the house serving both rooms.

That is the bit worth understanding. A multi-split means one condenser instead of two: less clutter outside, one set of pipework, one power supply, and each room still setting its own temperature independently. The bedroom can sit at 19 degrees overnight while the dining room does something completely different at Sunday lunch.

The outdoor unit went high on wall brackets around the side, out of the way of the path, with the pipework run nine metres back to the rooms in white trunking to match the house. Where the condenser goes and where the rooms are do not have to be the same place - that is a design decision, not a constraint.

Two Mitsubishi Electric wall units, 2.0 kW each, one per room
Single 4.2 kW outdoor unit serving both
Down to 19 dB(A) on the lowest fan setting
Built-in Wi-Fi on both units, controlled room by room from the MELCloud app
Heating as well as cooling, rated to work down to -15 degrees C outside
Backed by a 7-year manufacturer warranty as a Mitsubishi Business Solutions Partner

If you have been assuming air conditioning means building work, it usually does not. Free, no-obligation home survey - call 01628 522802.

19/10/2026

Part two of three ⏳

Last week we posted the big open-plan kitchen system at a house in Beaconsfield. This week we were back for the master bedroom.

A bedroom asks for something different. The kitchen job was about capacity - 9.5kW to deal with glass, an oven and an open-plan space that had nowhere to dump its heat. A bedroom needs almost the opposite: enough output to drop the room a few degrees on a warm night, and then the ability to run quietly enough that you forget it is on.

This one is a 3.5kW Mitsubishi Electric wall unit, and at its lowest fan speed it sits at 18 dB(A). For context, a quiet bedroom at night is usually around 25 to 30 dB. The unit is quieter than the room.

It also means the house can set each room independently. The kitchen runs hard through a summer afternoon while the bedroom barely ticks over overnight, and neither is compromising for the other.

Mitsubishi Electric MSZ-AY35VGK2, 3.5 kW
A+++ in cooling, SEER 8.7, with SCOP 4.7 and A++ in heating
Down to 18 dB(A) on the lowest fan setting
Built-in Wi-Fi, controlled room by room from the MELCloud app
Heating as well as cooling, so the bedroom is warm in January too
Backed by a 7-year manufacturer warranty as a Mitsubishi Business Solutions Partner

One system left at this property, going into a new outbuilding once the building work is finished.

If you are doing a house in stages, that is completely normal and often the sensible way to do it. We will plan the whole property up front, run what we can while the walls are open, and come back as each room is ready.

Free, no-obligation home survey - call 01628 522802.

18/10/2026

Wrapping up the week five minutes from the office

Most of our residential work takes us across Bucks, Berks and Oxfordshire, so there is something quietly satisfying about a job you could walk to.

We finished Friday in Bourne End, a stone's throw from the marina, fitting a black Mitsubishi Electric Kirigamine Zen into a new extension that is nearly finished. The client has been living with the building work for months, and the air conditioning is one of the last things to go in before the room becomes a room.

The protective film stays on until the builders are finished. No sense fitting a gloss black panel and then letting it collect plaster dust.

The Zen is the unit we suggest when someone says they do not want to see it. There are no visible louvres across the face, the panel is flat and glossy, and the black finish against a white wall looks like a design choice instead of a compromise. It is also one of the quietest units on the market at 19 dB(A) - about the level of a whisper.

Mitsubishi Electric Kirigamine Zen, 2.5 kW, black
A+++ in cooling, SEER 9.1
Down to 19 dB(A) on the lowest fan setting
Built-in Wi-Fi, controlled from the MELCloud app
Heating as well as cooling, so the extension works in January too
Backed by a 7-year manufacturer warranty as a Mitsubishi Business Solutions Partner

Four systems went in this week: a three-room multi-split in Amersham, a large open-plan kitchen in Beaconsfield, two caged single-splits in Slough and this one. Different houses, different problems, same answer.

If you are building an extension, we are still happy to take a look while the walls are open!

Free, no-obligation home survey - call 01628 522802.

17/10/2026

Two systems, two cages, one visit ❄️

We finished a two-system installation in Slough this week - a pair of Mitsubishi Electric Elegance wall units, one at 2.5kW and one at 3.5kW, each on its own outdoor unit.

The part worth talking about is the cages.

The client asked for both condensers to be fitted inside steel anti-theft guards. He had seen outdoor units taken before and wanted the same precaution on this house. It is a reasonable thing to want: a condenser is several thousand pounds of equipment, it lives outside, and it is often in the one part of the property nobody overlooks. A cage bolted through the brick turns a two-minute job into one nobody bothers with.

It is not something most people think to ask for, and we do not push it as standard - but if your unit sits somewhere quiet, down a side return or behind a gate, it is worth a conversation.

We also installed both power supplies with the help of our neighbours at First Light Electrical. That matters more than it sounds: a lot of installs stall because the air conditioning is in and the electrician cannot come until next week. Fully coordinated, one visit, nothing left hanging.

Two Mitsubishi Electric Elegance single split systems, 2.5kW and 3.5kW
Dedicated power supplies
Steel security cages to both outdoor units
Heating as well as cooling, so both systems work all year
Backed by a 7-year manufacturer warranty as a Mitsubishi Business Solutions Partner

Free, no-obligation home survey - call 01628 522802.

16/10/2026

One unit. The whole open-plan ground floor ❄️

Open-plan kitchens are lovely to live in and difficult to cool. Bifolds and roof lights pour heat in all afternoon, the oven adds more at exactly the wrong time of day, and because the space is open there is nowhere for that heat to go.

We have just finished the first phase of a three-system install in Beaconsfield, starting with the kitchen. It runs on a single Mitsubishi Electric Mr Slim wall unit at 9.5kW - a commercial grade system in a domestic setting, because a room this size needs the capacity.

The outdoor unit went down the side alley rather than on a visible elevation, with the pipework run in trunking along the brickwork and the isolators grouped neatly on the wall. Two of them, because the next system is already planned.

Mitsubishi Electric Mr Slim PKA-M100KA3, 9.5kW cooling
A+ in both heating and cooling - SEER 5.80, SCOP 4.00
R-32 refrigerant
MELCloud app control alongside the wireless handset
Backed by a 7-year manufacturer warranty as a Mitsubishi Business Solutions Partner

Two more single splits follow at this property, for the master bedroom and a new outbuilding. Planning the same? Getting the first system in while the building work is live saves money on the ones that follow.

Free, no-obligation home survey - call 01628 522802.

Address

Bourne End
SL85YS

Telephone

+441628522802

Website

http://www.graysmaintenanceservices.co.uk/

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