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WHLS

Last checked: 30 October 2026

Installer Selection Mistakes to Avoid

5 min readPublished Updated

White air source heat pump unit standing on a stone patio beside a red brick house wall, with potted plants

This page is for homeowners who want to avoid the usual traps when choosing an installer. It lists common mistakes and what to do instead. Many of them come from sales pressure. Our qualified provider list guide covers the checks that prevent them.

For the broader overview, read our guide: Any Qualified Provider List for UK Homeowners.

Independent guide. We are not a lender or a government body. Always check current scheme rules with the official provider.

The common mistakes

Each mistake below can leave you without protection or funding. Most are easy to avoid once you know them. Read the list before any installer visits.

  • Accepting cold calls or doorstep offers. Find installers through the MCS and TrustMark registers instead.
  • Signing on the day. Take time to compare quotes. RECC bans high-pressure selling.
  • Accepting a verbal quote. Ask for a written, itemised quote every time.
  • Paying a large deposit without protection. RECC and HIES members provide deposit protection.
  • Believing "government approved" claims without checking. Confirm MCS and TrustMark status yourself.

What to do instead

A few habits protect you from all of these mistakes. They take little time. Use them with every installer.

  1. Find installers on official registers.
  2. Verify certification and consumer code membership.
  3. Get two or three written quotes.
  4. Confirm deposit protection in writing.
  5. Use the seven-day cooling-off period to review the contract.

If you have already made a mistake

Act quickly if you signed under pressure. You may be able to cancel within the seven-day cooling-off period. Contact the installer's consumer code if you have a dispute. HIES offers free dispute resolution.

Frequently asked questions

Is a cold call about a free upgrade genuine?

Treat it with caution. Contact the scheme or your council directly instead.

What if I signed on the day?

Check your contract. RECC and HIES members give a seven-day cooling-off period.

How do I protect my deposit?

Use an installer in RECC or HIES. Both codes include deposit protection.

An installer says they are government approved. Is that true?

Check their MCS and TrustMark status yourself. Do not rely on the claim.

So you can avoid sales traps and keep your deposit, warranty and funding protected.

WHLS Editorial Team

Our editorial team writes independent, plain-English guides on home energy finance. We review guides when scheme rules change.

References

  1. MCS – Find an installer (opens in a new tab)
  2. TrustMark (opens in a new tab)
  3. RECC – Renewable Energy Consumer Code (opens in a new tab)
  4. HIES – Home Insulation and Energy Systems (opens in a new tab)
  5. Energy Saving Trust – Consumer protection (opens in a new tab)
  6. Financial Conduct Authority – Financial Services Register (opens in a new tab)

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