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What is a condensate pipe, and who should deal with it?

A condensate pipe on a condensing boiler carries water the boiler produces while it runs, usually to a drain. In Cheshire that pipe is part of a gas appliance job, so this page tells you who to call and gives no repair steps.

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By the QuoteZila editorial team. Editorial policy.

What are people usually pointing at?

In Cheshire a condensate pipe almost always means the plastic run that leaves a condensing boiler and carries the water that boiler makes to a drain, a hopper, or a soakaway the installer chose. Homes in Crewe, Nantwich and Sandbach are the ones this page is written around first. The pipe is outside or in a garage on many houses, so it looks like a simple plumbing offcut. It is still part of how that boiler was installed.

This page does not print a diameter, a fall or a lagging thickness. This page does not print a figure, because we could not find two dated public sources that agree on one. It does not tell you to pour water on the pipe, to cut it, to cap it, or to open the boiler. If you only know that a white pipe is dripping, or that the boiler has stopped in cold weather, write that down and stop there.

A later page will go further into boiler condensate as its own question. This one stays on who should look, and on how not to mix the pipe up with something else.

Anyone in the UK can post a job or register. QuoteZila is new, so replies depend on which engineers have joined near you [QZ5].

Why this is a gas job

HSE says anyone employed to work on gas appliances in domestic premises must be a Gas Safe registered engineer and competent in that area of gas work [S1]. The back of the ID card shows the competencies [S1]. If you are in doubt, HSE says you can check the engineer on the Gas Safe Register [S1]. Do that yourself before you hire.

Gas Safe Register. QuoteZila is not affiliated with this organisation.

Look the engineer up on the Gas Safe Register before you hire. We don't check insurance, qualifications or registrations, so please check these yourself before you hire.

If you suspect the appliance is unsafe, HSE says it is illegal to use it [S1]. Turn it off and do not touch it until a Gas Safe registered engineer has checked it [S1]. If you smell gas, use the emergency service rather than a quote form. This page does not repeat a repair method, because a method would be the engineer's, from the appliance instructions.

HSE also strongly advises that gas appliances, flues and pipework are serviced at least annually by a Gas Safe registered engineer [S1]. An annual service is not the same booking as a pipe that has split. Say which of the two you want.

What if the pipe is not from a boiler?

Not every dripping plastic pipe is a condensate pipe. A waste from a sink, a overflow from a cistern, and a drip from an air-conditioning unit can look similar from the garden.

GOV.UK lists putting in a fixed air-conditioning system among projects that might need building regulations approval, and says that approval is different from planning permission [S2]. You might need both [S2]. If the pipe leaves an air-conditioning unit, say so, and do not book it as boiler work. If you cannot tell, say you cannot tell. Do not cut the pipe to find out.

A soakaway used only for boiler condensate is a different question again. This page does not decide whether that discharge is allowed. Soakaway drains are covered separately, and they are not a boiler repair.

What should you say when you book?

  • The appliance: combi, system boiler, or you do not know.
  • Whether the boiler is showing a code, without taking the cover off to look inside.
  • Where the pipe runs: outside wall, garage, into a hopper, into a drain, or you cannot see the end.
  • Whether the problem is a drip, a split, a blockage you can see, or a boiler that has stopped.
  • The town and postcode.
  • Whether anyone in the house is without heating or hot water.

Citizens Advice says some traders charge for a quote, so ask before the engineer comes [S3]. A quote is a fixed price and an estimate is a rough guess [S3]. Try to get the price in writing [S3]. If an advert says there is no call-out charge, the Advertising Standards Authority says that claim is fair only when there is no charge for travelling to the premises, the initial diagnosis, or any other charge before you agree the work [S4]. Ask the question in those words.

A business must register for VAT when taxable turnover over the last 12 months goes over £90,000 [S5]. Ask whether the repair total includes VAT.

Jobs you might post

These are examples, not taken from real job posts.

  • The boiler has stopped and a plastic pipe on the outside wall looks blocked with ice. You have not poured anything on it. Ask a Gas Safe engineer to look.
  • The white pipe from the boiler is dripping onto the path. Ask for a written price that says whether the pipe is repaired or replaced, and whether the boiler is opened.
  • You are not sure whether a dripping pipe is from the boiler or from a bathroom above. Say that. Do not ask anyone to cut it before they have identified it.

How do you compare engineer quotes?

Ask which appliance they are competent for, and look at the ID card rather than the van livery [S1]. Ask whether the price includes a return visit if the boiler needs a part. Citizens Advice says the quote should show a fixed total, a breakdown, how long the price lasts, and whether VAT is included [S3]. A much lower figure can be a smaller piece of work [S3].

We don't check insurance, qualifications or registrations, so please check these yourself before you hire.

This page says what a condensate pipe is and who should deal with it, with no repair steps, while the boiler condensate pipe follows the inspection sheet's checks for size, support and termination.

Heating engineers are the trade page for boilers. Plumbers cover water pipes that are not gas appliances. The plumber cost guide is about reading a plumbing price, not about gas work. Up to five matched local businesses can reply [QZ2]. QuoteZila is free for customers and local businesses [QZ1].

This page is general information, not professional or legal advice. QuoteZila does not check Gas Safe, WaterSafe, NFRC, NICEIC or other registrations against the register on your behalf: look them up yourself.

Honest status: QuoteZila is new. We're starting in Cheshire, beginning with Crewe, Nantwich and Sandbach, and growing area by area. Anyone in the UK can still post a job or register a business. How fast you get quotes depends on how many local businesses have joined near you. Businesses can register and receive jobs straight away. We don't check insurance, qualifications or registrations, so please check these yourself before you hire.

Posting a job is not open yet

What do people ask about condensate pipes?

Can I thaw or reroute a boiler condensate pipe myself?

No. This page does not describe a way to warm, cut, extend or join that pipe. If the boiler has stopped, leave the casing alone. HSE says it is illegal for anyone to use a gas appliance they suspect is unsafe, and that it should be turned off and left until a Gas Safe registered engineer has checked it.

Who is allowed to work on the boiler?

HSE says anyone employed to work on gas appliances in a home must be a Gas Safe registered engineer and competent in that area of gas work, and that the competencies are on the back of the engineer's ID card. Check the card, and check the register yourself. QuoteZila does not do that check for you.

Is an air-conditioning drip the same pipe?

No. A pipe from a fixed air-conditioning unit is a different brief from a boiler condensate pipe. GOV.UK lists putting in a fixed air-conditioning system among alterations that might need building regulations approval. Say which appliance the pipe leaves, or say that you do not know.

How often should a gas appliance be looked at?

HSE strongly advises that gas appliances, flues and pipework are installed, regularly maintained and serviced at least annually by a Gas Safe registered engineer. That is maintenance advice. An annual service is a different booking from a pipe that has split.

Does QuoteZila check heating engineers?

No. We don't check insurance, qualifications or registrations, so please check these yourself before you hire. You can report a quote or a business from your job page.

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Sources

  1. QZ1: QuoteZila product fact. QuoteZila home and jobs copy.
  2. QZ2: QuoteZila product fact. QuoteZila terms, customers.
  3. QZ5: QuoteZila product fact. QuoteZila FAQ.
  4. S1: Domestic gas FAQs, HSE. Accessed 2026-10-25. https://www.hse.gov.uk/gas/domestic/faqs.htm
  5. S2: Building regulations approval, GOV.UK. Accessed 2026-10-25. https://www.gov.uk/building-regulations-approval
  6. S3: Before you get work done on your home, Citizens Advice. Accessed 2026-10-25. https://www.citizensadvice.org.uk/consumer/getting-home-improvements-done/before-you-get-building-work-done/
  7. S4: Call-out charges, Advertising Standards Authority. Accessed 2026-10-25. https://www.asa.org.uk/advice-online/call-out-charges.html
  8. S5: Register for VAT, GOV.UK. Accessed 2026-10-25. https://www.gov.uk/register-for-vat