10 Solar Installer
Warning Signs
Know the red flags before you sign a solar contract in Scotland.
Quick answer
The clearest warning signs of a poor solar installer are no MCS certificate on request, vague equipment details, no written warranty, no roof survey before quoting and pressure to sign quickly. A quote far cheaper than the rest is another red flag. If you spot any of these, ask questions in writing or walk away.
Last updated: 1 November 2026
Not all solar installers in Scotland are created equal. Some cut corners. Some use pressure tactics. Some disappear after installation. This guide covers the 10 warning signs that should make you walk away — no matter how good the price looks.
1. No MCS Certificate on First Request
Why This Matters:
MCS certification is mandatory for warranty protection and SEG payments. Any legitimate installer shows this immediately.
What to Do:
Ask for their MCS number. Verify it at mcscertified.com. If they hesitate or can't provide it within 24 hours — walk away.
2. Vague About Panel Brand and Model
Why This Matters:
Panel quality varies dramatically. Cheap panels degrade faster and generate less over 25 years.
What to Do:
Demand exact brand and model. Google the datasheet. Check warranty terms. Accept only Tier 1 panels (LG, Longi, JA Solar, Trina, etc).
3. No Written Warranty Documentation
Why This Matters:
Verbal promises mean nothing. You need written warranties: product (10-15 years), performance (25 years), workmanship (10 years minimum).
What to Do:
Request written warranty documents before signing. If they say 'it comes after install' — that's a red flag.
4. Won't Provide a Previous Customer Reference
Why This Matters:
Legitimate installers have hundreds of happy customers who will vouch for them.
What to Do:
Ask for 3 references from the last 6 months. Call them. Ask about response time, quality, and post-install support.
5. Doesn't Survey the Roof Before Quoting
Why This Matters:
Every roof is different. Shading, orientation, pitch, and structural capacity all affect system performance.
What to Do:
Never accept a quote without a physical roof survey. Remote quotes based on Google Maps are guesswork.
6. No Commissioning Included in Quote
Why This Matters:
Commissioning is the final testing and handover process. Without it, your system may not work optimally.
What to Do:
Check the quote itemization. Commissioning should be explicitly listed. If it's not — query it.
7. No DNO Notification in Their Process
Why This Matters:
Distribution Network Operators (DNO) must be notified of all solar installations. This is a legal requirement.
What to Do:
Ask: 'Do you handle DNO notification?' If they say 'that's your responsibility' — walk away. It's their job.
8. No Monitoring Solution Offered
Why This Matters:
How will you know if your panels are working? Modern installations include monitoring via app or online portal.
What to Do:
Ask what monitoring system comes with the install. If none — that's a warning sign of a cheap, corners-cut job.
9. No Scottish Physical Address
Why This Matters:
If things go wrong, you need to be able to visit their office. PO boxes and virtual offices don't count.
What to Do:
Google their address. Check on Street View. If it's a residential house or serviced office — be cautious.
10. Quote Dramatically Lower Than All Others
Why This Matters:
If one quote is far cheaper than others for the same system, there's a reason. Cheaper panels, no warranty, or they'll disappear after install.
What to Do:
Get 3 quotes. If one is an outlier (much cheaper or much more expensive), investigate why before proceeding.
What a Good Installer Looks Like
MCS Certified
Shows MCS certificate immediately. Number verifiable at mcscertified.com.
Transparent
Provides detailed quotes. Explains panel specs, warranties, and process clearly.
Reviews
Plenty of recent, independent reviews, and a clear record of putting problems right.
No Pressure
Gives you time to think. Never pressures you to sign on the day.
Physical Office
Real Scottish address. Verifiable on Google Maps. Phone answered during business hours.
Written Everything
Written quote. Written warranty terms. Written contract with cooling-off period.
Related guides
Compare quotes from vetted installers
Use these checks on every quote you receive, including the ones we arrange. We install through MCS-certified partners. Interest-free credit up to £30,000, subject to status.
FAQ
Questions about warning signs
What is the biggest warning sign with a solar installer?
Pressure to sign on the day is the single biggest red flag. A reputable installer gives you time to think, leaves the quote with you, and is happy for you to compare it with other quotes before deciding.
How do I check if a solar installer is MCS-certified?
Ask for their MCS number and verify it at mcscertified.com. If they hesitate, cannot provide it within 24 hours, or say it comes after installation, walk away. We install through MCS-certified partners and you can verify the number yourself.
Is a solar quote that is much cheaper than the others a good thing?
No. If one quote is dramatically cheaper than others for the same system, something is missing — cheaper panels, no warranty, no scaffolding, or they may disappear after install. Always get at least three written quotes and investigate any outlier.
Should a solar installer survey my roof before quoting?
Yes. Every roof is different — shading, orientation, pitch and structural capacity all affect system performance. Never accept a quote based only on a satellite image. A physical or detailed remote survey is essential for an accurate price.
What should I do if a solar installer will not put warranty terms in writing?
Do not sign. You need written warranty documents covering the panel performance warranty (typically 25 years), the inverter warranty (5 to 10 years), and the workmanship warranty (ideally insurance-backed). Verbal promises are not enforceable.
Can I cancel a solar contract after signing?
Consumer Contracts Regulations give you a 14-day cooling-off period to cancel if you signed at home or remotely. Check your contract states this clearly. If it does not, ask why before signing.