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Vaillant ecoTEC plus no hot water

Vaillant ecoTEC plus issues – Is there no hot water coming from your ecotec plus boiler?

There you are, standing in the shower, waiting to soak off the day’s stress when you’re met with a torrent of cold water.

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Not exactly the way you had planned on relaxing at the end of the day! So now you need to find out why your Vaillant boiler isn’t producing hot water.

In this guide, we’re going to look at all the reasons why the problem might be happening. Some of the most common Vaillant boiler problems include pressure issues and faulty valves. On older models, then pilot lights not staying alight is often the cause of the issue.

Thankfully, you’ll be able to fix some of the problems yourself. But for others, you’re going to need to rely on your boiler warranty, your boiler cover plan or calling out a heating engineer.

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The Vaillant ecotec plus

The ecoTEC Plus range of Vaillant boilers are well known for their high levels of efficiency. Though, with over 140 years of experience, it should really be no surprise that this is a boiler brand associated with consistently raising the bar within the heating sector.

The Vaillant ecoTEC is available as a combi boiler as well as a conventional or system boiler. That means that it’s capable of supplying a central heating system and hot water no matter the size of the home.

Key features Of Vaillant ecoTEC Plus boilers

Quiet Mark approved

With an incredibly quiet operation, you’re not going to be disturbed while the Vaillant ecoTEC heats the water for your home.

vSMART™ smartphone app

Compatible with the vSMART™ app, you’ll be able to control your boiler no matter where you are. And with smart technology comes the ability for the system to begin to understand your heating needs resulting in optimum use of energy and reduced bills.

Modulation down to 16%

Boiler modulation is the ability of the boiler to turn down the output. By reducing its output to just 16%, it avoids the boiler having to continually switch on and off to achieve the desired heating requirements. In turn, wear and tear on the boiler is reduced, and energy efficiency levels improve.

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Vaillant boiler error codes

All boilers display an error code when there are problems. Each boiler manufacturer uses a different range of error codes and they can even be specific to a particular model of a new boiler. So, when you get a new boiler make sure you keep the manual somewhere safe so that if you have problems then you know what each error code means.

The common Vaillant boiler problems associated with a no hot water problem are:

F22 error code: Low water pressure

The boiler continually monitors the water pressure in the system, and if it drops below a predetermined level, then the F22 error code is displayed. While all pressures lose some pressure over time, if it’s a sudden drop, then it’s likely to mean a bigger issue.

F29 error code: Flame extinguished

This error is caused by a boiler lockout. This then prevents the boiler from producing heating and hot water. The boiler lockout can be due to gas valve settings and problems with the condition of the ignition unit or ignition leads.

F61 error code: Gas valve failure

It’s likely to be a faulty gas valve that’s going to cause this error code. It might be because it’s been incorrectly adjusted or because it’s become faulty but either way faulty gas valves need to be checked out and potentially replaced by a qualified engineer.

F75 error code: Faulty pump or pressure sensor problem

This is a common problem on a Vaillant boiler. It’s displayed when the boiler isn’t able to detect the appropriate level of pressure when the pump is in operation. This needs an engineer to come out and check the boiler to determine if the lack of hot water is caused by a faulty pump or pressure sensor that’s no longer providing correct readings.

If you’re seeing an error code displayed that’s not on our list, then the next step is to have a look at your boiler manual for a complete list of all codes.

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What causes a combi boiler to have this problem?

This is where the engineer has to take on his detective skills because there is a whole range of Vaillant boiler problems that can cause the system to stop heating hot water. We’ve researched some of the more common reasons why you might be having this problem.

Don’t forget that it’s illegal for anyone other than a professional Gas Safe engineer to install, maintain or fix your gas boiler. So while this guide will provide you with an insight into potential issues for your hot water problems, you will need to call on the services of a heating engineer to resolve most of them.

If you have an electric boiler, we still don’t recommend poking around in the inner workings of your boiler; you might cause more problems than there was to begin with!

Supply problems

First things first, there’s always the potential for this to be a really quick fix or to be nothing at all to do with your boiler.

Gas supply problems

The majority of boilers in the UK use gas as their primary energy source. So before doing anything else, check that other gas appliance, such as your gas cooker, are working. If they’re not then not having hot water could be down to the lack of an energy supply.

That then means a call with your gas supply company to get things sorted out.

Electricity supply problems

Even if your Vaillant boiler uses gas, it still needs a small amount of electricity to function. You’ll use an electric switch, for example, to turn your gas boiler on. The ignition system will also use electricity along with the pump that moves and carries the hot water to the different areas of your home.

So, check other appliances to see if it’s an electricity supply fault but also bear in mind that the issue could be associated with an electrical fault within the boiler. Even the best combi boiler, system or regular boilers can have an electricity supply option.

Water supply problems

If there’s no water getting to the boiler, then that’s definitely going to cause problems with getting hot water! Turn on a cold tap to make sure that you have a good supply of water coming into your home.

Flame issues

Next up are problems associated with the flame. A gas boiler produces hot water by pumping it through piping that passes over a series of gas flames. As the water passes the flames, it heats up pretty much the same as water would in a kettle. So, when there are problems with the flame, then the water can’t then be heated.

With older boilers, you used to be able to see the pilot light through a display window but most modern boilers no longer have this feature which means you then need to rely on the error codes to know what’s going on. In fact, many boilers no longer even have a pilot light!

Flame extinguished

When the code F29 flashes up, then this is related to the flame that heats the water being extinguished. You’ll often see that the boiler ignites and then it shuts off. This is caused by problems with the flame sensors, the flues, and the airways. An engineer will need to check that the flue system is all connected correctly and assess whether the seals on the flue need replacing.

Incorrect flame detection

The Vaillant ecoTEC boiler will display the F27 error code when there are issues with the gas supply making ignition unsafe. As a result, the boiler goes into lockout mode and so won’t heat hot water until the problem is resolved.

Fix incorrect flame detection

When you see Vaillant boiler error code F27, then that usually means that there has been an incorrect flame detection. To get this resolved, will need the services of a heating engineer to check within the boiler unit. The fault can be caused by moisture getting into the electrical parts and also through the ignition leads becoming worn out.

Worst case scenario would be problems with the printed circuit board (PCB). The PCB is essentially the brains of the system and, generally, repairing is not a cost-effective solution. This then means that a gas safe registered engineer will need to order and then fit a replacement for you.

Issues with valves

Whether it’s the diverter valve, the gas valve or the pressure relief valve, all of them can mean no hot water if they become faulty.

Faulty diverter valve

The role of the diverter valve in a combi boiler is to open and close to direct hot water to where it’s needed. The means that when a hot tap is turned on or when heating is needed, the diverter valve ensures that the hot water gets to the right place.

So, that means that if you’re only getting lukewarm water from the hot taps, but you’re getting hot radiators, or good hot water pressure but cool to the touch radiators, then the diverter valve is probably what’s causing the problem.

This will again need the help of a heating engineer who will be able to assess whether the valve simply needs cleaning or whether it needs replacing.

Faulty pressure release valve

The pressure relief valve regulates the pressure to prevent your boiler from exploding. It does this by receiving excess pressure. When the valve fails, rather than causing a huge issue, the boiler responds by dropping the pressure and so preventing it from getting to a dangerous level.

Because the valve is situated outside of the boiler, it is possible for you to replace it without calling in an engineer, This involves draining the tank before removing the old valve and then fitting the new one.

However, most homeowners prefer to get a gas safe registered engineer to do the job for them. This ensures that the boiler is then up and working and generating hot water before they leave.

Faulty gas valve

When a Vaillant boiler shows fault code F62, it means that there’s a problem with the gas valve and this is what controls the flow of gas to the pilot light and to the burner. When the gas valve opens, it allows the fuel to flow and the boiler ignites.

When the valve fails to open or let enough gas in, then the boiler isn’t able to light and so there’s no way to heat your hot water. This then needs a qualified professional to come out and check the heating system for you.

System pressure problems

Boiler pressure is essential to a correctly functioning boiler. It’s the pressure that allows the system to heat water arriving from the mains supply. When the pressure drops or becomes too high, then the boiler will shut off automatically. This then prevents any hot water from being sent around the home heating system.

To check the pressure of your boiler, take a look at the boiler’s pressure gauge to see if it’s at the recommended level. You might also see an error code on the display to indicate that there’s a pressure-related issue. Don’t forget that your pressure may be fine but you’re getting incorrect readings from a faulty pressure sensor.

It’s not unusual for pressure to vary in a boiler. But, thankfully, some problems around boiler pressure can be fixed without needing to call in specialist help. That means that you might be able to get it back to heating water in no time at all.

Too much pressure

It’s possible that when you add water to your boiler system, that you accidentally add too much. That then means that the pressure is too high and as a result, the boiler goes into lockdown mode and stops heating any hot water.

To reduce the pressure, some of the water needs to be released from the system, and this is done by bleeding the radiators.

1. First of all have a cloth to hand and something to catch the water in.

2. Then using a radiator valve, slowly twist the valve on the radiator in an anti-clockwise direction.

3. You’ll hear air escaping first and then water will begin to flow out of the valve. If you’ve had the heating on recently, do be careful as it will be hot water that comes out.

4. Let out a small amount of water from each radiator and check the pressure gauge after each one.

Low water pressure

If the water coming from the hot water tap seems to have little pressure and the radiators furthest from the boilers never get really warm, then low pressure could be the cause. When the pressure gets very low then it will cause the boiler to stop operating.

For the Vaillant ecoTEC Plus, the pressure level should be between 1.0 and 2.0 bar when the boiler is cold. If the indicator is below 0.8 bar, then that indicates low water pressure. The system then needs to be filled up with water before switching the boiler back on.

You can increase the boiler pressure by using the built-in filling loop attached to your boiler; there’s no need to call in a gas safe registered engineer unless you don’t feel confident to sort out the problem.

On most models of boiler, the filling loop is now permanently attached to the boiler and this is the case with this Vaillant boiler. With older boilers, you may need to attach an external filling loop.

You’ll usually see a silver pipe with a flexible connection along with tap valves on either end. By turning the valves, you’ll hear the water begin to enter the system. Make sure that you keep watching the pressure gauge so that you can turn the valves off again once it’s reached the correct level.

You’ll know when the boiler pressure is back at the recommended levels because either:

  • The fault code has disappeared
  • Or the boiler is functioning and you’ve now a good supply of hot water coming from the hot tap

Does adding water fix the problem?

Topping up the water might just be a short term fix to a low water pressure problem. But, if the boiler keeps losing pressure then it’s likely that you have leaking pipes somewhere and that’s causing the water pressure to drop.

While this might be a tiny issue right now, it will get worse with the risk of causing further problems and damaging your home.

A frozen condensate pipe

Cold weather can mean a frozen condensate pipe then causes problems for your boiler and results in no hot water. But, the good news is that this is a problem that homeowners can fix themselves. That means there’s no need to call out a gas safe registered engineer to fix it for you.

The condensate pipe allows the wastewater to be channelled away from the boiler and disposed of in a drain. Where possible, the pipe will be fitted so that it empties into an internal drain, but in some homes, the only option is for them to be fitted outside.

This then causes the pipe to freeze in cold weather. Boiler installation teams will try to find a way of fitting the condensate pipe to drain internally. However, sometimes there is no option but to fit them outside. That then causes the pipe to freeze in cold weather.

How to thaw a frozen condensate pipe

First of all, find the frozen part of the pipe. This usually happens where there’s a bend or a dip in the pipe. There are two ways to thaw it out:

1. Hold a hot water bottle, warm cloth or heating pad warmed in the microwave onto the frozen section of pipe.

2. Use a watering can or jug to carefully pout the hot water over the frozen section of the pipe. It’s really important not to use boiling water as the condensate pipe is plastic and it could melt!

3. Now you’ll need to reset your boiler. Because it wasn’t able to get rid of the wastewater, the boiler will shut down to prevent any further damage from being caused.

How to prevent a frozen condensate pipe

It’s always better to prevent a problem from happening to begin with. To prevent the condensate pipe from freezing in the first place there are a few steps that you can take before winter arrives:

– Cover the condensate pipe with foam pipe

– Leave the heating on during the night. This stops the condensate pipe from getting cold, to begin with, and then freezing

– Turn your thermostat up as this reduces the volume of condensate

A broken thermocouple

The thermocouple acts as a safety device. It turns the gas supply off when the pilot light goes out, this ensures that there is gas leaking into the home. When a thermocouple is faulty, the pilot light won’t stay alight and so there’s no heating of hot water. A broken thermocouple will need to be replaced by a heating engineer.

Reset problem

Like all technology, sometimes all that’s needed is a reset to get it working again.

Thankfully, modern combi boilers are designed to be incredibly reliable, and very safe. That does however mean, that when it does detect an issue, then it will shut down to prevent the problem from escalating. And that means no hot water until the issue is resolved.

Sometimes, a reset is all that’s needed to get the boiler up and working. Even if there was another problem, that has now been fixed, a reset is still often needed so that the boiler can recognise that the issue is no longer there.

The way of resetting a boiler varied between different models. For Vaillant ecoTEC boilers, you’ll need to go to the boiler settings and then press the reset button and hold it in for one second.

Check that the boiler is switched on

We know this sounds really obvious, but sometimes it’s the simple things that get overlooked. To turn on Vaillant ecoTEC boilers:

1. Turn the on/off controls from the ‘0’ position, round to the ‘1’ position.

2. Make sure that the radiator temperature control is set at the maximum radiator temperature.

3. Check that the remote programmer is turned to the on the setting.

4. Check that the room thermostat is set to cause the heating to come on.

Timer problem

The timer on your regular or system boiler dictates when the water is heated and then sent through your central heating to warm your home. Most homeowners have the heating set to come on in the morning when they get up and then again in the evening. But, if there’s no hot water running through the central heating when you expected it, then it could all be down to a problem with the timer.

It might have been an accident change in the time or a power cut has caused the timer to get out of sync with the correct time of day. Maybe it’s been since the clocks changed and the timer hasn’t been updated. Either way, this could be an easy fix to your hot water problems.

Vaillant boiler problems might also be created with problems using smart controls, especially if you’re getting to grips with a new boiler. Don’t forget to check the app to see if any of the settings are causing the boiler not to supply the hot water you were expecting.

Time issues don’t apply to a combi boiler as these heat hot water on demand.

Is it time for a new boiler?

If you keep having problems with your boiler or the expense to repair it is building up, then now might be the time to look for a new boiler replacement. With higher levels of efficiency and technology to make real savings on your heating bills, a new boiler may not cost as much as you think over the long term.

Then you’ll have peace of mind knowing that your hot water supply is, once again, reliable.

As well as the option of going for another Vaillant boiler, there are a number of highly recommended boiler manufacturers that could be the right choice for your new heating system.

We’ve made it incredibly easy to select your new boiler and have it installed. Just provide a few details in order to get online new boiler cost and quotes, installed as quick as next day.

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