Laars Heating Systems · NeoTherm Residential
Laars NTH105
The Laars NTH105 is the second NeoTherm Residential boiler size: a floor-standing modulating condensing unit at the 105 step between NTH080 and NTH150, on the numeric Hold/Lockout code system of Document 1252K.
Key figures
- Max input
- 105 MBH
- Max CSA output
- —
- AFUE
- —
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Laars NTH105 in practice
The NTH105 is the 105 size column of the NeoTherm Residential parts list — the step between the 080 and 150 models in the 080-285 MBTU/h NTH range documented by I&O Document 1252K. It shares the floor-standing condensing platform, operator interface and diagnostics of the series.
The interface reports numeric codes as Holds or Lockouts from Appendix B of Document 1252K, with entries for internal faults, pumps, fans, the safety chain, high limits and sensors; the service manual (Document 1291) repeats the tables as Appendix 1 with section references such as B18 for the variable-speed fan drive.
Best suited to
- Homes and light commercial loads that outgrow the NTH080 step
- Floor-standing condensing plants in the 105 MBH class
- Owners who want the full NeoTherm Residential diagnostics in a mid-small size
Applicability and support
- Model number
- NTH105
- Canadian availability
- available
- Production status
- current
- ROMA supplies
- Confirmed at consultation
- ROMA services
- Confirmed at consultation
- Warranty
- Not verified
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.
Specifications
Published specifications
Values as published by Laars Heating Systems. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Maximum input (as printed) | 105 MBH | Second NeoTherm Residential size — the installation manual covers Model NTH 080-285 MBTU/h and its parts list carries a 105 column (Document 1252K). |
| Domestic hot water | ||
| Domestic hot water | Boiler model — the control's error table includes DHW high-limit (80) and DHW sensor (93) entries per Appendix B | |
| Operating limits and other | ||
| Fuel | Natural gas or propane | Fuel configuration per the NeoTherm Residential manuals. |
| Error reporting | Numeric codes reported as Hold (H) or Lockout (L) — Appendix B of the I&O manual (Document 1252K) and Appendix 1 of the service manual (Document 1291) | |
Manuals
Alerts documented for this model
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32-46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 59
- 61
- 62
- 63
- 64
- 67
- 68
- 70
- 78
- 79
- 80
- 81
- 82
- 91
- 92
- 93
- 94
- 95
- 96
- 97
- 98
- 99
- 100
- 105
- 106
- 107
- 108
- 109
- 110
- 111
- 113
- 122
- 123
- 128
- 129
- 130
- 131
- 132
- 137
- 149
- 150
- 152
- 153
- 154
- 155
- 156
- 157
- 158
- 159
- 160
- 161
- 164
- 165
- 172
- 174
- 175
- 176
- 178
- 184
- 185
- 186
- 187
- 188
- 189
- 192
- 193
- 194
- 195
- 196
- 197
- 198
- 199
- 200
- 201
- 202
- 203
- 204
- 205
- 207
- 210
- 211
- 212
- 213
- 214
- 215
- 216
- 217
- 218
- 219
- 220
- 221
- 222
- 223
- 224
- 225
- 226
- 227
- 228
- 229
- 230
- 231
- 232
- 234
- 235
- 236
- 237
- 238
- 239
- 240
Frequently asked questions
What sizes sit around the NTH105?
The NeoTherm Residential parts list runs 80, 105, 150, 210 and 285, so the NTH105 sits between the NTH080 and NTH150. The correct step follows from a heat-loss calculation.
Where is the NTH105 code table printed?
Appendix B on page 72 of the installation manual (Document 1252K) and Appendix 1 of the service manual (Document 1291) both list the codes with Hold or Lockout classes and procedures.
Does the NTH105 display a code history?
Yes — the diagnostics chapter describes a history of lockouts and alarms (the 15 most recent lockouts are available under Info/Diagnostics/History), plus read-only analog sensor and firing-rate values.
Questions about the Laars NTH105?
Describe what the boiler is doing and get a straight answer about the next step.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
- Laars Heating Systems — official site · accessed September 7, 2026
- Laars — contact (Laars Canada, 9 Brigden Gate, Halton Hills, Ontario) · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.