MCS Installer Checklist: Don't Hire Anyone Without These 7 Checks
MCS certification is mandatory for heat pump grants (BUS), but not all MCS installers are equal. This checklist helps you separate the excellent from the adequate.
Why MCS Matters
- Required for £7,500 Boiler Upgrade Scheme grant
- Required for Smart Export Guarantee (SEG) payments
- Ensures installer follows UK standards (MCS 001, BS 7671)
- Protects you with insurance-backed warranties
The 7-Point MCS Installer Checklist
1. Verify MCS Certification (Takes 2 Minutes)
Don't trust the badge on their website. Verify directly:
- Go to mcscertified.com/find-an-installer
- Search by company name or postcode
- Check their certification covers your technology (heat pump, solar, battery)
- Confirm certification is current (not expired)
Red Flag:If they can't provide their MCS certificate number immediately, walk away.
2. Ask for 3 Recent References (Same Technology)
Not just any references – installations of the same system type within the last 12 months.
What to ask the references:
- Did the installer complete on time and on budget?
- Any issues during or after installation?
- How did they handle snagging/warranty issues?
- Would you hire them again?
3. Confirm Insurance Cover
MCS requires installers to have insurance, but limits vary. Ask for proof of:
- Public liability insurance: Minimum £2 million
- Professional indemnity insurance: For design work
- Insurance-backed warranty: Protects you if company goes bust
4. Heat Loss Survey (Heat Pumps Only)
This is mandatory for BUS grant and prevents oversizing/undersizing.
Major Red Flag:If installer quotes a heat pump without visiting your home or measuring rooms, they're guessing. Go elsewhere.
5. Fixed Price, Not Estimate
Get a fixed-price quote that includes:
- Full equipment specification (brands, models)
- Labour and materials
- BUS grant deducted (should show £7,500 discount for heat pumps)
- Scaffolding (if needed for solar/battery)
- Electrical upgrades (consumer unit, cabling)
- Any pipework or radiator changes
Avoid quotes with "subject to survey" clauses unless survey is free and happens before you commit.
6. Warranty Length and Terms
MCS standard is minimum 2 years workmanship warranty. Good installers offer:
- Heat pumps: 5-7 year parts warranty + 2 year workmanship minimum
- Solar panels: 10-12 year product warranty + 25 year performance guarantee
- Batteries: 10 year warranty (check degradation terms)
7. Check Online Reviews (But Read Carefully)
Look for:
- Trustpilot: Check "1 star" reviews for patterns (every company gets some bad reviews)
- Google Reviews: Focus on detailed reviews, not just star ratings
- Checkatrade/Trustatrader: Verify they're listed and check scores
Watch for: Companies with only 5-star reviews (suspicious) or sudden spike in bad reviews (often means quality dropped after expansion).
Red Flags: Walk Away If You See These
- Pressure to sign today ("grant ends soon" – it doesn't)
- Won't provide MCS certificate number or references
- Heat pump quote without home survey
- Deposit over 25% upfront (standard is 10-25%)
- Cash-only or personal bank account (not company account)
- "Too good to be true" pricing (£3k heat pump = will fail)
How Many Quotes Should You Get?
Minimum 3, ideally 5 quotes.Here's why:
- Heat pump quotes can vary £3,000-£8,000 for identical systems
- Helps you spot outliers (suspiciously cheap or expensive)
- Different installers recommend different brands/approaches
Use our installer finder to request quotes from verified MCS installers in your area:
Questions to Ask During Quote Visit
For All Technologies:
- What's your MCS certificate number?
- How long have you been MCS certified?
- Can you provide 3 references for [heat pump/solar/battery] installations?
- What's included in your warranty?
- Who handles warranty claims if you go out of business?
- What's your typical installation timeline?
- Will you apply for planning permission if needed?
Heat Pump Specific:
- Will you conduct a full heat loss survey to BS EN 12831?
- What size heat pump do you recommend and why?
- Do I need to upgrade my radiators?
- What's the expected flow temperature?
- Will you handle the BUS grant application?
- Do you include commissioning and handover training?
Solar Panel Specific:
- What panel brand/model and why?
- What's the panel degradation rate?
- Is scaffolding included in price?
- Will you register for Smart Export Guarantee?
- Do I need a new consumer unit?
Typical MCS Installation Costs (After Grants)
Heat Pumps (After £7,500 BUS Grant)
- Small (5-8 kW): £500 - £4,500
- Medium (8-12 kW): £2,500 - £6,500
- Large (12+ kW): £4,500 - £8,500
Solar Panels (No grant, but 0% VAT)
- 3-4 kW system: £5,000 - £7,000
- 4-6 kW system: £6,500 - £9,500
- 6-10 kW system: £8,500 - £14,000
Battery Storage (0% VAT if with solar)
- 5 kWh battery: £3,000 - £4,500
- 10 kWh battery: £5,500 - £7,500
- 15 kWh battery: £8,000 - £11,000
Bottom Line
MCS certification is the baseline, not the destination. An MCS badge proves an installer meets minimum standards, but these 7 checks help you find installers who exceed them.
The best installers welcome scrutiny, provide detailed answers, and never pressure you to sign immediately.
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