Croydon & the CR postcodes
New boiler installation in Croydon and the CR postcodes
A combi boiler supplied and fitted starts at £1,950, and the figure we give you after the survey is the figure you pay. We quote after looking at the property rather than over the phone, because the two things that decide which boiler suits your house are how much heat it loses and how much water your incoming mains can actually deliver, and neither of those can be guessed from a postcode. We are Gas Safe registered under number 919881, and once the job is commissioned we notify Building Control for you.
What you get
What the job includes
- A survey before any price is given, with a room-by-room heat loss calculation and a measured flow rate taken at the kitchen tap, so the boiler is sized to the house rather than to the biggest model on the van.
- Removal and disposal of the old boiler, and of the cylinder, tanks or back boiler if they are coming out. Where a back boiler is removed we deal with the builder’s opening and leave the chimney safe.
- A full system cleanse to BS 7593, fresh inhibitor and a magnetic filter fitted on the return. Most manufacturers now make this a warranty condition rather than an upgrade, so it is in the price.
- A scale reducer on the cold mains. Croydon water is hard enough that this is a condition of most boiler warranties here, not an optional extra, and we fit one as standard.
- Time and temperature controls, plus the extra efficiency measure Boiler Plus requires on every combi. Usually load compensation or a smart control, and we explain the difference before you pick one.
- Gas tightness testing, a gas rate check, flue integrity checks, flue gas analysis with a calibrated analyser, and the Benchmark commissioning book filled in and left with you.
- Building Control notification through the Gas Safe competent person scheme, with the compliance certificate issued to you. That is the document a buyer’s solicitor asks for.
- Warranty registered with the manufacturer in your name, and a written record of what was fitted including model, serial number, gas rate and the controls specified.
Local knowledge
Hard chalk water and narrow Victorian mains
Croydon’s water comes off the chalk of the North Downs, and it is hard. Hardness across the borough is usually reported somewhere in the high 200s to low 300s of milligrams per litre as calcium carbonate. Boiler manufacturers generally treat anything above 200 as a hard water area, and most of them make a scale reducer on the cold feed a condition of the warranty at that level. It is a quietly important detail, because a combi heats hot water through a narrow plate heat exchanger, and in water like ours an unprotected one furs up and starts giving you hot-then-cold showers within a few years. If a quote for a Croydon installation does not include water treatment, the warranty behind it is doing less than it appears to.
The second thing that shapes what we can fit here is the incoming supply. A great deal of Croydon housing is late Victorian and Edwardian terrace, particularly around Thornton Heath, Selhurst, South Norwood and Broad Green, and a lot of it is still fed by the original narrow main, sometimes lead. A combi cannot deliver more hot water than the mains gives it. A 30kW combi will produce roughly twelve litres a minute at a usable temperature, but only if twelve litres a minute is coming in. Where we measure ten, fitting a 35kW boiler instead buys you nothing at all, and it will short-cycle and run less efficiently for the rest of its life. On those houses the honest answer is often a smaller boiler, or upgrading the incoming main to 25mm before the boiler goes in. We measure the flow rate on the survey, and we will tell you which of those you are looking at.
How it goes
What happens, step by step
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Survey
We come out and look at the property. That means measuring the rooms and the windows for a heat loss calculation, checking the radiators and the existing pipework, looking at where the flue can terminate and where the condensate can discharge, and running the kitchen tap into a gauge to see what the mains actually delivers. We also check what is under the floor, because on the older terraces the existing pipework is sometimes 8mm microbore, which limits what a new system can do. The survey is where the price comes from, so it is not a five minute look at the old boiler.
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Sizing
The heat loss figure tells us what the house needs to stay warm on a cold day. In practice most Croydon three-bedroom houses come out somewhere between 8kW and 14kW, which is a good deal less than people expect. A combi is then sized by its hot water output rather than its heating output, so the number on the badge is about how fast it can fill a bath, not about how warm the house gets. We size to the measured flow rate and the number of bathrooms in use. Going bigger than that costs more, wastes gas through cycling, and does not improve anything you would notice.
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Written quote
You get a fixed written price covering the boiler, the controls, the filter, the scale reducer, the flush, the fitting, the certification and the disposal. If the survey found something that has to be dealt with first, such as a mains upgrade or a run of pipework that needs replacing, it is priced as a separate line so you can see what it is and decide. The quote names the specific boiler model and the warranty length that comes with it. Nothing is left as an allowance to be settled later, and we do not price on the doorstep at the end of a sales visit.
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Fitting
A straight combi swap in the same position is usually a single day. Moving the boiler, converting from a conventional system to a combi, or taking out a back boiler and cylinder runs to two or three. We isolate and drain down, take the old appliance out, run any new gas, water and condensate pipework, and hang the new boiler. Where the condensate has to run outside we use 32mm insulated pipe rather than the 22mm waste that causes the frozen condensate no-heat calls every January. We work Monday to Saturday, and we clear up and take the old boiler away with us.
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Flush and treat
Before the new boiler is fired on an existing system, the system gets cleansed to BS 7593. On most Croydon installations that means a chemical cleanse with the system running, then a thorough flush through, then inhibitor dosed to the correct concentration and a magnetic filter fitted on the return. Skipping this is the single most common reason a new boiler fails early on an old system: decades of magnetite in the radiators ends up in the new heat exchanger. We also fit the scale reducer on the cold mains at this stage. Both are recorded in the Benchmark book as evidence for the warranty.
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Controls and Boiler Plus
Since April 2018, Boiler Plus has required every gas boiler installed in England to be at least 92 per cent efficient and to be fitted with time and temperature control. A combi has to have one additional measure on top of that: flue gas heat recovery, weather compensation, load compensation, or smart controls with automation and optimisation. We go through the four with you rather than defaulting to whichever is cheapest to fit. Load compensation and weather compensation cost less and quietly save more; smart controls are the ones people usually want because they can be set from a phone. Either way it is included, not an upsell.
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Commissioning and paperwork
The boiler is commissioned to the manufacturer’s procedure: gas tightness test, gas rate check, flue integrity check and a flue gas analysis with a calibrated analyser, then the flow temperature set for condensing operation rather than left at the factory maximum. We fill in the Benchmark checklist, register the warranty in your name, and notify Gas Safe, who notify Croydon Council building control on our behalf under the competent person scheme. Your Building Regulations compliance certificate follows from Gas Safe. We also show you how the controls work before we leave, which sounds obvious and is very often skipped.
Before you ring
Questions we get asked
How much does a new boiler cost in Croydon?
Our combi installations start at £1,950 and that figure includes the boiler, controls, magnetic filter, scale reducer, system flush, fitting, certification and taking the old one away. A full central heating system, meaning boiler, radiators, pipework and controls, starts at £3,400. Where a job costs more than the starting figure it is because of something specific we found on the survey, such as moving the boiler, a mains upgrade or removing a back boiler and cylinder, and that will be itemised on the quote rather than absorbed into a round number.
What is Boiler Plus and does it apply to me?
Boiler Plus is the part of the building regulations that has applied to boiler installations in England since April 2018. It sets a minimum efficiency of 92 per cent, requires time and temperature controls with every gas boiler, and requires combis to have one of four extra measures: flue gas heat recovery, weather compensation, load compensation, or smart controls with automation and optimisation. It applies to any boiler we install for you, including a straight like-for-like replacement, and meeting it is part of the quoted price rather than an add-on.
Do you notify Building Control, and how do I get the certificate?
Yes. We are Gas Safe registered, which is a competent person scheme, so we notify Gas Safe and Gas Safe notifies Croydon Council building control on your behalf. You do not need to apply to the council yourself or pay a separate building notice fee. Gas Safe then issues your Building Regulations compliance certificate, which usually arrives within a couple of weeks of the job. Keep it: it is the document a buyer’s solicitor will ask for when you sell, and replacing a lost one later is a nuisance.
Can I legally install a boiler myself?
No. Working on a gas appliance or gas pipework in a domestic property is restricted by law to a Gas Safe registered engineer, and installing a boiler is also notifiable work under the building regulations. Beyond the legal position, an unregistered installation cannot be notified, will not receive a compliance certificate, and voids the manufacturer’s warranty completely. It will also show up as an unresolved item during a sale. Buying the boiler yourself and having us fit it is a different matter, though we would usually rather supply it so the warranty sits cleanly with the installation.
How long does it take to fit a new boiler?
A like-for-like combi replacement in the same position is normally one day, and you will usually have heating and hot water back the same evening. Moving the boiler to a different room, or converting from a conventional system with a cylinder and loft tanks to a combi, takes two to three days because there is far more pipework involved. Removing a back boiler from behind a gas fire is at the longer end of that, as the fireplace opening has to be dealt with afterwards. We tell you which of these your job is at the quote stage.
Do I need to replace my radiators at the same time?
Usually not. Existing radiators are generally fine as long as they are sound and the system is properly cleansed, and we would rather flush and keep them than sell you a set you do not need. Two situations do change that. If the heat loss calculation shows a room is short of output, that radiator is undersized and running the new boiler at a low flow temperature will make it obvious. And if a radiator is badly corroded internally it will keep shedding sludge into the new boiler. We flag either on the survey with the cost, and it stays your decision.
Do you need access to every radiator on the day?
Yes, please. The system has to be drained and refilled, every radiator needs bleeding and balancing once the new boiler is running, and the cleanse is only effective if we can get flow through all of them. That means we need to reach the valves at both ends of each radiator, so it helps if furniture is pulled clear beforehand. We also need access to the stopcock, the gas meter and the loft if there is a tank up there. If a radiator is boxed in or behind a fitted unit, tell us at the survey rather than on the morning.
Is a 12 year old boiler too old to keep repairing?
Twelve years is around the point where the arithmetic starts to change, though age alone is not the deciding factor. What matters more is whether parts are still available, how many faults it has had in the last two years, and what it is costing to run. A boiler repair is £110 and an annual service is £90, so a single fault on an otherwise sound appliance is rarely a reason to replace it. Three faults in two winters on a boiler whose parts are being discontinued is a different conversation, and we will say so plainly rather than quoting you a new one by reflex.
Can you fit a combi in a flat?
In most cases yes, and a good deal of the housing we work on across central Croydon and the CR0 blocks is flats. The constraints are usually the flue and the consent rather than the boiler. A flue terminal has to sit a set distance from openable windows, boundaries and other terminals, which is tighter on a balcony or a light well, and above certain heights a specific flue system is needed. If you are a leaseholder, the freeholder or managing agent normally has to approve the work and may ask for evidence of our registration and insurance, which we can supply.
What if there is no gas supply to the property?
Some of the ex-local-authority blocks around the borough were built without a gas riser and are electric throughout, and a gas combi is not an option there. An electric boiler can be, though it needs a genuine look at the consumer unit and the incoming supply first, because the current draw is significant and the running cost per unit is a good deal higher than gas. We will tell you honestly whether it makes sense for your flat, what the alternatives are, and where the case for one is weak. A survey is the only sensible way to answer that one.
Can I get a free boiler through a grant?
Government help with boiler replacement has run through a series of schemes over the years, and eligibility has generally been tied to receiving certain benefits and to the energy rating of the property. We are not a grant-funded installer, so we cannot process an application for you. If you think you might qualify, the places to check are the current government scheme and Croydon Council’s housing team. If a grant does not cover you, or you would rather not wait on one, we will quote the job normally.
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