Home All Services Commercial Air Conditioning Air Conditioning Heat Pump Servicing Unvented Cylinders Water Treatment Plumbing Advice & Guides Case Studies About Contact Call 07717 846247
water_heaterG3 Qualified · Megaflo

Megaflo Servicing & Repair

G3 qualified servicing, fault repair and inspection of Megaflo unvented cylinders across Orpington, Bromley, Sevenoaks and Kent. £140 with no VAT and a written inspection record every visit.

verified_userG3 Qualified
descriptionWritten Record Issued
money_offNo Call-Out Fee

paymentsMegaflo Servicing

  • check_circle£140 full G3 annual service, no VAT
  • check_circle£270 Megaflo + heat pump together
  • check_circleEco, Eco Plus & SystemReady
  • check_circleWritten inspection record every visit
  • check_circlePre-purchase inspections available
buildMegaflo Faults

The Megaflo Problems I See Most

Megaflo is the most common unvented cylinder in this part of Kent and South East London, and it is a genuinely well-built unit. Almost everything that goes wrong with one is a control or a valve rather than the cylinder itself — which matters, because it usually means a repair rather than a replacement.

Water discharging from the tundish

The most common Megaflo call by a wide margin. A safety valve is passing because the system has nowhere to expand. On Megaflo Eco models that is the internal air bubble having collapsed; on models with an external vessel it is the expansion vessel losing its charge or never having been commissioned to the property's incoming pressure.

Hot water pressure dropped, cold is fine

Almost always the strainer in the inlet control group. It quietly fills with debris from the mains and throttles the hot supply. Cleaning it is a routine part of a service and it is skipped constantly.

Lukewarm water or slow reheat

Usually the immersion or the thermostat on a Megaflo heated electrically, or a scaled or underperforming coil on an indirectly heated one. Both are diagnosable on site rather than by guesswork.

Failed temperature and pressure relief valve

T&P valves weep, stick, or fail to reseat after operating. A weeping one wastes water and signals a fault upstream that needs finding, not just a new valve.

"You need a new cylinder"

You often do not. I have replaced a combination valve and re-primed an expansion vessel on cylinders that another firm had already quoted to replace. I will tell you honestly which side of that line yours falls on.

helpFAQ

Megaflo Questions

Yes. I'm G3 qualified and service, repair and inspect Megaflo unvented cylinders across Orpington, Bromley, Sevenoaks and Kent — including Megaflo Eco, Eco Plus and SystemReady.
£140 with no VAT for a full G3 annual service including a written inspection record. With a heat pump service in the same visit it is £270.
A safety valve is passing. On Megaflo the usual cause is the internal air bubble or the expansion vessel losing its charge, so the cylinder has nowhere to expand into. It should never be left.
If the cold is fine but the hot has dropped off, it is very often the strainer in the inlet control group filling with debris from the mains. Straightforward to clean once you know where to look.
Typically 15 to 25 years if it has been serviced. The stainless steel vessel usually outlasts the controls — the expansion vessel, valves and immersion are the parts that fail and they are all replaceable.
Quoted at a reduced rate for the second on the same visit. Tell me when you book and I will give you a figure up front.
I explain what it is, what it costs, and how urgent it genuinely is. You decide. Fixed price agreed before any repair work starts.
Almost all of them. It makes no difference who fitted it or who serviced it last.
The common ones, yes — valves and vessel components. Anything unusual I quote and order, then come back.
Annually. Manufacturers require documented annual servicing to keep warranties valid, and annual testing of the safety devices is the accepted standard for a pressurised vessel.

Book Your Megaflo Service

£140 with no VAT, written inspection record every visit, across Orpington, Bromley, Sevenoaks and Kent.

call07717 846247
Warning Signs

What to Watch For

Almost every cylinder I attend had been dropping hints for months. None of these are dramatic, which is exactly why they get ignored.

Rusty or discoloured hot water

Worth investigating quickly. On an indirect cylinder it can point at the coil; elsewhere it may be pipework rather than the vessel.

Reduced flow at every hot outlet at once

Points at the cylinder or its controls rather than an individual tap, and is usually the pressure reducing valve or the strainer.

Hot pressure down, cold still fine

That specific pattern points at restriction between the mains and the cylinder — usually a silted strainer in the inlet control group.

Water in the tundish

Even an occasional drip after the cylinder heats means a safety valve has operated. It is the clearest warning you get and the one most often ignored.

The pressure gauge keeps falling

Topping up regularly is not normal. Water is escaping somewhere, and each top-up brings in oxygenated water that corrodes from the inside.

Costs

What You Will Pay

What I will not do is quote for a replacement cylinder before measuring your incoming mains pressure and checking the expansion vessel charge. A lot of cylinders get replaced when a valve would have fixed them.

Repairs are quoted separately at a fixed price agreed before I start — typically a combination valve, an expansion relief valve, a T&P valve, or re-priming a vessel. None are expensive jobs.

A full G3 annual service is £140 with no VAT — I am not VAT-registered, so that is the whole price rather than a figure with twenty percent waiting behind it.

photo_cameraOur Work

Repair Rather Than Replace

Most cylinder faults are a valve or a vessel, not a dead cylinder.

Unvented cylinder mid-repair with inlet group removed
An unvented cylinder mid-repair — old inlet group and strainer removed. Pictured cylinder is an RM Cylinders Stelflow; the same work applies across brands including Megaflo
callCall Gary — 07717 846247