Laars Heating Systems · NeoTherm Residential
Laars NTH150
The Laars NTH150 is the mid-size NeoTherm Residential boiler: a floor-standing modulating condensing unit at the 150 step of the 080-285 MBTU/h range, on the numeric Hold/Lockout code system of Document 1252K.
Key figures
- Max input
- 150 MBH
- Max CSA output
- —
- AFUE
- —
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Laars NTH150 in practice
The NTH150 is the 150 column of the NeoTherm Residential parts list in Document 1252K — the middle of the five NTH sizes and a common landing point for larger detached homes. It is the smallest size Laars also lists under the paired NTV water heater models (NTV sizes 150-285) in the service manual, Document 1291.
Diagnostics are the series-standard numeric codes with Hold or Lockout classes — Appendix B of Document 1252K, page 72 — supported by the 11.G diagnostics menus that show sensor values, digital inputs and outputs and a lockout history. The service manual repeats the tables as Appendix 1 with references into Section B procedures.
Best suited to
- Larger homes whose heat-loss calculation reaches the 150 step
- Buildings pairing the NTH150 with a separate water heater for hot water
- Floor-standing modulating installations in the middle of the NeoTherm Residential range
Applicability and support
- Model number
- NTH150
- 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) | 150 MBH | Mid NeoTherm Residential size — the installation manual covers Model NTH 080-285 MBTU/h and its parts list carries a 150 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
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Frequently asked questions
Is the NTH150 a combi boiler?
No. The NTH is a modulating boiler, and the residential pair documented in the service manual is the NTH boiler plus the NTV water heater (150-285 sizes). The control's error list still includes DHW high-limit and DHW sensor codes used in DHW arrangements.
How does the anti-short-cycle function work on the NTH?
Per Document 1252K the controller includes an anti-short-cycle (ASC) function whose timer can delay the boiler start after a call for heat ends, and hold-only code 61 flags the anti-short-cycle state — it is not a lockout fault.
What safety devices appear in the NTH code tables?
Code 63 (SAFETY CHAIN OFF) lists the devices on the safety string — condensate level switch, heat-exchanger fusible link, optional flow switch, pressure switch and low-water cut-off, plus the gas-pressure switches on CSD-1 models — each to be tested when diagnosing the chain.
Questions about the Laars NTH150?
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.