Patterson-Kelley · Error codes
Patterson-Kelley 10194 — Cannot Write Leadlagdhwdemand
10194
cannot write LEADLAGDHWDEMAND. Priority will occur. The table classifies it as Hold (H).
Applies to
This domestic hot water fault code is displayed by the NURO touchscreen control with Sola burner control on MODU-FIRE FD (N750–N3000) and THERMIFIC VELOX (N750–N2000) appliances equipped with the NURO touchscreen control, as documented in NURO Advanced User's Guide, doc 1004905979 Rev G (March 2016), Appendix C Error Reference Table (1004905979 Rev G). Codes can differ between controller generations, so always check the manual that matches your unit.
- Patterson-Kelley P-K MODU-FIRE FD
- Patterson-Kelley P-K THERMIFIC VELOX
- P-K MODU-FIRE FD N750
- P-K MODU-FIRE FD N1000
- P-K MODU-FIRE FD N1500
- P-K MODU-FIRE FD N2000
- P-K MODU-FIRE FD N2500
- P-K MODU-FIRE FD N3000
- P-K THERMIFIC VELOX N750
- P-K THERMIFIC VELOX N1000
- P-K THERMIFIC VELOX N1500
- P-K THERMIFIC VELOX N1700
- P-K THERMIFIC VELOX N2000
Controller: NURO touchscreen control with Sola burner control. Source manual: 1004905979 Rev G (2016-03).
Why a code is not a diagnosis
A DHW code involves the hot-water side: sensors, flow, the mixing/bypass valve or the DHW heat exchanger. It does not say whether the fix is a sensor, a valve or a flush.
Safe things to observe
- Note the code and whether the problem follows a hot-water draw or appears at all times.
Do not
- Do not open the appliance to test DHW components yourself.
How professional service helps
- A technician tests the DHW sensors, flow switch and valve circuits, and cleans the DHW path where the manual directs.
- Combustion and safety devices are verified with an analyser and the manufacturer's procedure after any repair.
Where ROMA provides on-site service
On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.
Frequently asked questions
Can I clear this code myself?
Clearing a code without fixing its cause usually just brings it back. Note the code, check the safe items on this page, then call a licensed technician. If your appliance manual describes a user reset for this exact code and it stays away, no call may be needed.
Boiler locked out? Call with the alert text ready.
The brand, model and this alert are passed along when you request service online, so the technician arrives prepared.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
- NURO Advanced User's Guide, doc 1004905979 Rev G (March 2016), Appendix C Error Reference Table · 1004905979 Rev G · accessed September 9, 2026
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.