How to help your customers fix a frozen condensate pipe

A frozen condensate pipe can be a nuisance in winter, potentially leaving people without heating or hot water. Here’s how you can advise customers with Vaillant boilers to solve the problem

Wednesday 24 January 2024

It’s the time of year when temperatures can plummet below zero, and heating installers get calls from concerned customers about frozen condensate pipes.

Usually made from white plastic, the condensate pipe allows the boiler condensate to escape from the boiler.

But if the condensate pipe terminates outside the property, it can freeze in winter temperatures – which can mean the boiler fails to start.

If this happens, it can leave residents without heating or hot water during the coldest time of the year.

But fixing a frozen condensate pipe is a relatively simple task – and it’s something that the resident can do, with a bit of expert guidance from you, their local installer.

Plus, by supporting your customers to solve the problem themselves, you’ll avoid unnecessary callouts, helping save their money and your own valuable time.

"Fixing a frozen condensate pipe is a relatively simple task – and it’s something that the resident can do, with a bit of expert guidance"

If you do get a call from a worried customer, you can give them a few simple tips to help them sort out the issue there and then.

Firstly, ask them to check the fault code on the display of their Vaillant boiler. If they see F.28 or F.29 flash up, it can mean that the condensate pipe is frozen.

Then, ask the customer to locate the condensate pipe. If it’s safe for them to get to, they can defrost it by pouring warm water over it, or warming it with a hot-water bottle.

But it’s vital to warn them not to pour boiling water on the pipe, as this can crack it.

Finally, they can prevent the now-defrosted condensate pipe from freezing up again by wrapping it in an old blanket.

There’s plenty of clear, helpful advice available on this topic from Vaillant, which you can send to your customers if they need further support.

Our new, comprehensive homeowner advice page features more information and a step-by-step guide to resolving a frozen condensate pipe.

We’ve also created a short video that outlines the solution:

If you’re installing a new or replacement boiler, there are several aspects to consider when positioning a condensate pipe, such as ensuring the discharge point is inside the property (such as an internal soil stack) to avoid potentially freezing conditions outside.

And when servicing a boiler, you can also check the existing condensate pipe to see if could be upgraded to meet the latest standards.

The Heating & Hotwater Industry Council has this industry guidance document, which provides further detailed instructions for installers.