Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
nationalheatingandac.com
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-20 09:30:28 UTC · ↺ Refresh
MX Hostnames
- nationalheatingandac-com.mail.protection.com
MX Priorities
- nationalheatingandac-com.mail.protection.com: 0
A / AAAA Records
- 104.21.16.104 (no PTR)
- 172.67.167.62 (no PTR)
- 2606:4700:3032::6815:1068 (no PTR)
- 2606:4700:3036::ac43:a73e (no PTR)
Mail Server IPs
No IPs resolved.
SOA Record
Raw SOA
guy.ns.cloudflare.com dns.cloudflare.com 2399144452 10000 2400 604800 1800
Primary NS (mname)
guy.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2399144452
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
paislee.ns.cloudflare.com
guy.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:sendgrid.net include:spf.protection.outlook.com -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
7 records- google-site-verification=6kZDI0iPxC_jAFf9RBAUN7QkaNoBPnH6HHyPi8SpV-k
- google-site-verification=N7GUWyxxA2bcgTxB6Uoqw_8_hxnGe_tcroyzc8FIwIA
- google-site-verification=wlXH5NK1VBPAikY1HpfQzIqSykP7qHOeghQa-QJX-Uo
- SPFv=spf1 include:sendgrid.net include:spf.protection.outlook.com -all
- 22sq73um0sfd70ctlsd6ljg05n
- 98i5ohsb92fd3kqt5m450803ff
- apple-domain-verification=JqhsMI9robIndK0m
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