Bosch Thermotechnology · Buderus GB142
Buderus GB142-30 kW
The Buderus GB142-30 kW was one of four GB142 condensing boiler sizes sold in Canada (24/30/45/60 kW). This size fired 31.8 to 106 MBH natural-gas input with 95 MBH CSA output; the model is now out of both the CA and US catalogs and is kept as a historical record with its manuals under the US discontinued-Buderus documentation library.
Key figures
- Max input
- 106 MBH
- Max CSA output
- —
- AFUE
- —
- Min input
- 32 MBH
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Buderus GB142-30 kW in practice
The GB142-30 kW is a size of the Logamax plus GB142 condensing boiler that Buderus sold in Canada in four wall-hung sizes — 24, 30, 45 and 60 kW. Per the IOM technical specifications (6720820104, 10.2017 US/CA), this size rated 31.8 to 106 MBH natural-gas input and 95 MBH CSA output, at 194 °F maximum flow temperature with the heater-water temperature set on the BC10 basic controller.
The GB142 is no longer in the Canadian or US condensing catalog, its documents live under the US 'Discontinued Buderus Products' library, and Canadian support continues only through Bosch's CA FAQ pages, which still walk owners through GB142 maintenance and the 3L/6A fault codes. New units are not listed for sale on either catalog, so this record is historical: it exists to serve owners diagnosing an installed unit.
Technicians diagnosing this size use the UBA 3 fault language documented in the GB142 Service Instructions (7214 9400): two-character service codes with numeric sub-codes and system-fault letters, each with its own structure diagram in chapter 7 'Diagnosis'. The IOM's technical specifications also note the 88% boiler-efficiency rating at 176/140 °F is based on European performance standards.
Best suited to
- Owners and technicians maintaining an installed GB142-30 kW
- Historic sizing reference: CSA output and input figures per the 2017 IOM
- Reading UBA 3 codes against the 7214 9400 service instructions
Applicability and support
- Model number
- GB142-30 kW
- Canadian availability
- historical
- Production status
- discontinued
- 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 Bosch Thermotechnology. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Rated thermal load, minimum (NG) | 32 MBH | 31,800 BTU/hr natural gas per the IOM technical specifications. |
| Rated thermal load, maximum (NG) | 106 MBH | 106,000 BTU/hr natural gas per the IOM technical specifications. |
| Output | ||
| CSA output | 95 MBH | 95,400 BTU/hr per the IOM technical specifications. |
| Efficiency | ||
| Boiler efficiency rating at max. capacity (176/140 °F) | 88 % | Manual note: performance figures at 176/140 °F are based on European performance standards; at 122/86 °F the rating is 97%. |
| Venting and air | ||
| Flue gas connection | 3" (80 mm); 3"/3" (80/80 mm) parallel for room-air-independent | |
| Physical and connections | ||
| Weight (without packaging) | 110 lb | Per the GB142 IOM technical specifications table. |
| Dimensions (W x H x D) | 28 × 22 × 18.7 in (712 × 560 × 475 mm), height × width × depth | Per the manual technical data table. |
| Maximum flow temperature | 194 °F | 194 °F (90 °C); heater water temperature 86-190 °F, set on the BC10 basic controller. |
| Maximum operating overpressure of boiler | 43.5 psi | 43.5 psi (3 bar). |
| Heat exchanger heating circuit volume | 0.7 gal | Heating-circuit volume of the heat exchanger. |
| Gas connection | 3/4" NPT | |
| Heating system water connection | 1" NPT | |
| Electrical | ||
| Electrical power consumption, full load | 117 W | |
| Operating limits and other | ||
| Fuel | Natural gas or propane | Separate NG and LPG ratings in the manual; LPG requires the gas conversion kit included with the appliance. |
Manuals
- GB142 Installation Manual (doc 6720820104, 10.2017 US/CA)6720820104 · 2017-10
- GB142 Service Instructions (doc 7214 9400, 12.2011 US/CA)7214 9400 · 2011-12
Alerts documented for this model
Frequently asked questions
Can I still buy a GB142-30 kW?
No. The GB142 appears in neither the CA nor the US condensing catalog and its manuals are filed under the US 'Discontinued Buderus Products' library. This record is historical, for owners of installed units.
What were the ratings of the GB142-30 kW?
31.8 to 106 MBH natural-gas input and 95 MBH CSA output, per the technical specifications in the 10.2017 IOM.
Which manual do I use for GB142 fault codes?
The GB142 Service Instructions, doc 7214 9400: chapter 7 'Diagnosis' covers codes such as 3L and 6A with structure diagrams, and Bosch's CA FAQ points to the same manual for the 3L and 6A troubleshooting steps.
Questions about the Buderus GB142-30 kW?
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
- Bosch Home Comfort Canada — Condensing Gas Boilers FAQ (GB142 Boiler Products) · accessed September 7, 2026
- Bosch Home Comfort US — Discontinued Buderus Products (documentation) · accessed September 7, 2026
- GB142 Installation Manual (6720820104) · accessed September 7, 2026
- GB142 Service Instructions (7214 9400) · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.