High-output, low-emission home comfort. The LCB700 36kW Internal Combi (LC) is Navien’s most powerful internal Blue Flame oil combi, delivering rapid hot water and efficient heating in a compact, installer-friendly chassis. Stainless steel heat exchangers, long flue runs and smart-ready controls make it a reliable upgrade for larger homes.
✅ Key Benefits
Strong DHW performance: up to 20 L/min (±15%) for showers and multiple taps.
Efficient & smart-ready: ErP A (93%); A+ with Navien Smart Plus controls.
Blue Flame, low NOx: modern burner technology for cleaner combustion.
Stainless steel primary & DHW heat exchangers for durability.
Flexible flueing: up to 21 m vertical / 20 m horizontal (Ø60/100 mm coaxial).
Compact footprint:600 × 600 × 860 mm for utility rooms/kitchens.
10-year parts & labour warranty (T&Cs apply).
⚙️ Technical Specifications
Model
LCB700 36kW LC – Internal Combi
Fuel
Oil, Blue Flame (HVO compatible)
CH Output (80/60°C)
29–36 kW
CH Output (50/30°C)
39 kW (max)
DHW Flow (±15%)
20 L/min
ErP Efficiency
A (93%); A+ with Smart Plus
Flue (Ø60/100)
20 m horizontal / 21 m vertical
Dimensions (W × D × H)
600 × 600 × 860 mm (internal combi)
Weight
≈ 91 kg (internal)
Noise
~56 dB(A)
Heat Exchangers
Stainless steel (primary & DHW)
Warranty
10 years (parts & labour) – registration & T&Cs apply
🏠 Ideal For
3–5 bedroom homes with higher hot water demand
Internal, floor-standing combi replacements
Upgrades from older, less efficient oil boilers
⚠️ Installation & Compliance
Must be installed and serviced by an OFTEC-registered engineer. Follow all local building regs and manufacturer guidance.
Delivery Times
All our deliveries are made by some of the countries most trusted couriers, including Royal Mail, PacelForce, DHL , Fastway Curriers
For most larger sized deliveries, you will receive a call from the courier an hour before the scheduled delivery time.
Free Delivery
Free delivery when you spend £150+ on all our stocked items, up to the maximum 20kg in weight (UK & Ireland Only) To be eligible for this service, you must place your order before 1pm on the previous day.
Delivery Drop Off
It is important to note that we use external shipping couriers. They are responsible for delivering the item(s) to the kerb-side. They are not responsible for delivering items into your home*.
*Please note, for large orders we advise that you seek assistance from friends or neighbours to assist with moving your order, as often the driver will not be able to assist you. Some items may be delivered on a pallet. It is your responsibility to dispose of the pallet, however, we recommend keeping it for the first 14 days in case you need to return your item(s).
Failed Deliveries
In the unlikely event that delivery is attempted when you are not at home, we will contact you by phone and re-book another time that suits you. Please note, there may be a re-delivery charge added at our discretion, which will be reviewed on a case by case basis.
Direct Deliveries from Distribution Centers
To help you receive your items as quickly as possible, parts of your order may be dispatched directly from a distribution center (Ie) Amazon. If this is the case, you will be contacted directly by them to arrange delivery for the products concerned. Please note, these items will arrive at a different time to products dispatched from our head warehouse. Some distribution centers may take between 2-3 days to deliver items.
Non-Stocked Items
Some items are ordered into our warehouse especially for your orders. This means there may be additional lead times on your order arriving. The estimated delivery time for non-stocked items is 5-7 working days.
For orders that contain a mixture of stock and non-stock items, excluding items delivered directly from distribution centers, we will deliver all items together. We will make you aware of this when we phone or email you to confirm the delivery date. You will be given the option to receive them separately as well, however there may be additional shipping charges.
Shipping Rates
All Orders to the UK & Ireland *ONLY*up to 20kg £150+ is Free
Pallet Rates are priced on application and order... delivery lead times will also vary based on post code.
Returns
Returns are subject too a 50% re-stocking charge.
- Items installed/fitted without professional understanding IE Oftec/SafeGas Registered Installer certificates, invalidate any warranty of said item bought.. This is however is at the companies discretion.
- All products must be inspected within 24hrs. Goods are non-returnable after this period.
To be eligible for a return, your item must be unused and in the same condition that you received it. It must also be in the original packaging.
Several types of goods are exempt from being returned. Goods including but not limited to printed circuit boards, control boxes, chemicals, hazardous materials, flammable liquids or gases. Please ask if you are unsure if you can return your goods.
Some items are not returnable such as PCB Boards and Boilers if they are opened, There also will be a 25% Handling fee for All Items if accepted for return.
To complete your return, we require a receipt or proof of purchase.
Please do not send your purchase back to the manufacturer unless otherwise instructed by Spares Direct.
There are certain situations where only partial refunds are granted (if applicable) Any item not in its original condition, is damaged or missing parts for reasons not due to manufacturer / supplier error Any item that is returned more than 30 days after delivery
Refunds (if applicable) Once your return is received and inspected, we will send you an email to notify you that we have received your returned item. We will also notify you of the approval or rejection of your refund. If you are approved, then your refund will be processed, and a credit will automatically be applied to your credit card or original method of payment, within a certain amount of days.
Late or missing refunds (if applicable) If you haven’t received a refund yet, first check your bank account again. Then contact your credit card company, it may take some time before your refund is officially posted. Next contact your bank. There is often some processing time before a refund is posted. If you’ve done all of this and you still have not received your refund, please contact us at info@sparesdirect.ie
Sale items (if applicable) Only regular priced items may be refunded, unfortunately sale items cannot be refunded.
Exchanges (if applicable) We only replace items if they are defective or damaged. If you need to exchange it for the same item, send us an email at info@sparesdirect.ie and send your item to: Unit 5 Dargan Industrial Park, 62 Dargan Crescent, Belfast BT3 9JP.
Unwanted goods or Failed deliveries of items bought If for any reason you order from us and the item has been shipped, but you no longer wish to have the item, the goods should be returned to us at the consumers cost. The price of goods will be refunded upon delivery/inspection (please note carriage cost will NOT be refunded. This also applies to missed deliveries/collection of goods from currier depot.
Shipping To return your product, you should mail your product to: Unit 5 Dargan Industrial Park, 62 Dargan Crescent, Belfast BT3 9JP.
You will be responsible for paying for your own shipping costs for returning your item. Shipping costs are non-refundable. If you receive a refund, the cost of return shipping will be deducted from your refund.
Depending on where you live, the time it may take for your exchanged product to reach you, may vary.
If you are shipping an item over £50, you should consider using a trackable shipping service or purchasing shipping insurance. We don’t guarantee that we will receive your returned item.
Navien LCB700 36kW Internal Combi Oil Boiler (LC)
*5-7 Days Lead time*
High-output, low-emission home comfort. The LCB700 36kW Internal Combi (LC) is Navien’s most powerful internal Blue Flame oil combi, delivering rapid hot water and efficient heating in a compact, installer-friendly chassis. Stainless steel heat exchangers, long flue runs and smart-ready controls make it a reliable upgrade for larger homes.
✅ Key Benefits
Strong DHW performance: up to 20 L/min (±15%) for showers and multiple taps.
Efficient & smart-ready: ErP A (93%); A+ with Navien Smart Plus controls.
Blue Flame, low NOx: modern burner technology for cleaner combustion.
Stainless steel primary & DHW heat exchangers for durability.
Flexible flueing: up to 21 m vertical / 20 m horizontal (Ø60/100 mm coaxial).
Compact footprint:600 × 600 × 860 mm for utility rooms/kitchens.
10-year parts & labour warranty (T&Cs apply).
⚙️ Technical Specifications
Model
LCB700 36kW LC – Internal Combi
Fuel
Oil, Blue Flame (HVO compatible)
CH Output (80/60°C)
29–36 kW
CH Output (50/30°C)
39 kW (max)
DHW Flow (±15%)
20 L/min
ErP Efficiency
A (93%); A+ with Smart Plus
Flue (Ø60/100)
20 m horizontal / 21 m vertical
Dimensions (W × D × H)
600 × 600 × 860 mm (internal combi)
Weight
≈ 91 kg (internal)
Noise
~56 dB(A)
Heat Exchangers
Stainless steel (primary & DHW)
Warranty
10 years (parts & labour) – registration & T&Cs apply
🏠 Ideal For
3–5 bedroom homes with higher hot water demand
Internal, floor-standing combi replacements
Upgrades from older, less efficient oil boilers
⚠️ Installation & Compliance
Must be installed and serviced by an OFTEC-registered engineer. Follow all local building regs and manufacturer guidance.
Delivery Times
All our deliveries are made by some of the countries most trusted couriers, including Royal Mail, PacelForce, DHL , Fastway Curriers
For most larger sized deliveries, you will receive a call from the courier an hour before the scheduled delivery time.
Free Delivery
Free delivery when you spend £150+ on all our stocked items, up to the maximum 20kg in weight (UK & Ireland Only) To be eligible for this service, you must place your order before 1pm on the previous day.
Delivery Drop Off
It is important to note that we use external shipping couriers. They are responsible for delivering the item(s) to the kerb-side. They are not responsible for delivering items into your home*.
*Please note, for large orders we advise that you seek assistance from friends or neighbours to assist with moving your order, as often the driver will not be able to assist you. Some items may be delivered on a pallet. It is your responsibility to dispose of the pallet, however, we recommend keeping it for the first 14 days in case you need to return your item(s).
Failed Deliveries
In the unlikely event that delivery is attempted when you are not at home, we will contact you by phone and re-book another time that suits you. Please note, there may be a re-delivery charge added at our discretion, which will be reviewed on a case by case basis.
Direct Deliveries from Distribution Centers
To help you receive your items as quickly as possible, parts of your order may be dispatched directly from a distribution center (Ie) Amazon. If this is the case, you will be contacted directly by them to arrange delivery for the products concerned. Please note, these items will arrive at a different time to products dispatched from our head warehouse. Some distribution centers may take between 2-3 days to deliver items.
Non-Stocked Items
Some items are ordered into our warehouse especially for your orders. This means there may be additional lead times on your order arriving. The estimated delivery time for non-stocked items is 5-7 working days.
For orders that contain a mixture of stock and non-stock items, excluding items delivered directly from distribution centers, we will deliver all items together. We will make you aware of this when we phone or email you to confirm the delivery date. You will be given the option to receive them separately as well, however there may be additional shipping charges.
Shipping Rates
All Orders to the UK & Ireland *ONLY*up to 20kg £150+ is Free
Pallet Rates are priced on application and order... delivery lead times will also vary based on post code.
Returns
Returns are subject too a 50% re-stocking charge.
- Items installed/fitted without professional understanding IE Oftec/SafeGas Registered Installer certificates, invalidate any warranty of said item bought.. This is however is at the companies discretion.
- All products must be inspected within 24hrs. Goods are non-returnable after this period.
To be eligible for a return, your item must be unused and in the same condition that you received it. It must also be in the original packaging.
Several types of goods are exempt from being returned. Goods including but not limited to printed circuit boards, control boxes, chemicals, hazardous materials, flammable liquids or gases. Please ask if you are unsure if you can return your goods.
Some items are not returnable such as PCB Boards and Boilers if they are opened, There also will be a 25% Handling fee for All Items if accepted for return.
To complete your return, we require a receipt or proof of purchase.
Please do not send your purchase back to the manufacturer unless otherwise instructed by Spares Direct.
There are certain situations where only partial refunds are granted (if applicable) Any item not in its original condition, is damaged or missing parts for reasons not due to manufacturer / supplier error Any item that is returned more than 30 days after delivery
Refunds (if applicable) Once your return is received and inspected, we will send you an email to notify you that we have received your returned item. We will also notify you of the approval or rejection of your refund. If you are approved, then your refund will be processed, and a credit will automatically be applied to your credit card or original method of payment, within a certain amount of days.
Late or missing refunds (if applicable) If you haven’t received a refund yet, first check your bank account again. Then contact your credit card company, it may take some time before your refund is officially posted. Next contact your bank. There is often some processing time before a refund is posted. If you’ve done all of this and you still have not received your refund, please contact us at info@sparesdirect.ie
Sale items (if applicable) Only regular priced items may be refunded, unfortunately sale items cannot be refunded.
Exchanges (if applicable) We only replace items if they are defective or damaged. If you need to exchange it for the same item, send us an email at info@sparesdirect.ie and send your item to: Unit 5 Dargan Industrial Park, 62 Dargan Crescent, Belfast BT3 9JP.
Unwanted goods or Failed deliveries of items bought If for any reason you order from us and the item has been shipped, but you no longer wish to have the item, the goods should be returned to us at the consumers cost. The price of goods will be refunded upon delivery/inspection (please note carriage cost will NOT be refunded. This also applies to missed deliveries/collection of goods from currier depot.
Shipping To return your product, you should mail your product to: Unit 5 Dargan Industrial Park, 62 Dargan Crescent, Belfast BT3 9JP.
You will be responsible for paying for your own shipping costs for returning your item. Shipping costs are non-refundable. If you receive a refund, the cost of return shipping will be deducted from your refund.
Depending on where you live, the time it may take for your exchanged product to reach you, may vary.
If you are shipping an item over £50, you should consider using a trackable shipping service or purchasing shipping insurance. We don’t guarantee that we will receive your returned item.
Política de reembolso
Returns
Returns are subject too a 50% re-stocking charge.
- Items installed/fitted without professional understanding IE Oftec/SafeGas Registered Installer certificates, invalidate any warranty of said item bought.. This is however is at the companies discretion.
- All products must be inspected within 24hrs. Goods are non-returnable after this period.
To be eligible for a return, your item must be unused and in the same condition that you received it. It must also be in the original packaging.
Several types of goods are exempt from being returned. Goods including but not limited to printed circuit boards, control boxes, chemicals, hazardous materials, flammable liquids or gases. Please ask if you are unsure if you can return your goods.
Some items are not returnable such as PCB Boards and Boilers if they are opened, There also will be a 25% Handling fee for All Items if accepted for return.
To complete your return, we require a receipt or proof of purchase.
Please do not send your purchase back to the manufacturer unless otherwise instructed by Spares Direct.
There are certain situations where only partial refunds are granted (if applicable) Any item not in its original condition, is damaged or missing parts for reasons not due to manufacturer / supplier error Any item that is returned more than 30 days after delivery
Refunds (if applicable) Once your return is received and inspected, we will send you an email to notify you that we have received your returned item. We will also notify you of the approval or rejection of your refund. If you are approved, then your refund will be processed, and a credit will automatically be applied to your credit card or original method of payment, within a certain amount of days.
Late or missing refunds (if applicable) If you haven’t received a refund yet, first check your bank account again. Then contact your credit card company, it may take some time before your refund is officially posted. Next contact your bank. There is often some processing time before a refund is posted. If you’ve done all of this and you still have not received your refund, please contact us at info@sparesdirect.ie
Sale items (if applicable) Only regular priced items may be refunded, unfortunately sale items cannot be refunded.
Exchanges (if applicable) We only replace items if they are defective or damaged. If you need to exchange it for the same item, send us an email at info@sparesdirect.ie and send your item to: Unit 5 Dargan Industrial Park, 62 Dargan Crescent, Belfast BT3 9JP.
Unwanted goods or Failed deliveries of items bought If for any reason you order from us and the item has been shipped, but you no longer wish to have the item, the goods should be returned to us at the consumers cost. The price of goods will be refunded upon delivery/inspection (please note carriage cost will NOT be refunded. This also applies to missed deliveries/collection of goods from currier depot.
Shipping To return your product, you should mail your product to: Unit 5 Dargan Industrial Park, 62 Dargan Crescent, Belfast BT3 9JP.
You will be responsible for paying for your own shipping costs for returning your item. Shipping costs are non-refundable. If you receive a refund, the cost of return shipping will be deducted from your refund.
Depending on where you live, the time it may take for your exchanged product to reach you, may vary.
If you are shipping an item over £50, you should consider using a trackable shipping service or purchasing shipping insurance. We don’t guarantee that we will receive your returned item.
Info@sparesdirect.ie
02895 434 399
Trustpilot
