4 Best External Gas Boilers [with Housing Units]

Spread the love

Normally, I wouldn’t recommend an external gas boiler and that’s because no sane gas engineer would even consider touching it when it’s raining/snowing. However, there is a quick solution to this!

The solution to installing a combi boiler into an outside electrical cabinet is with an integral frost protection. The customer I installed the last one for was grateful since he had little space to fit a boiler, or cylinder in his home. Plus, servicing outside is easy, with no mess and 100% safe too.

Many boilers (especially the high-end ones) often feature integral frost protection but check. Most don’t require ventilation too so air vents aren’t a must. Ensure the flue is fitted correctly and not too close to the wall. Majority of brands recommend a horizontal exit flue to be 25-100mm from a wall, but check with makers. This means that the flue will come out of the side of the cabinet. The best position to prevent water ingress.

What are the Best External Gas Boilers [cabinet]?

Let’s check out some of the top recommended boilers for outside:

  • Rinnai i150SN Condensing Gas Boiler


This is our no.1 pick since it is designed to offer an outdoor reset for optimized home heating.


  • It is not really heavy
  • Offers the comfort of whole home heating
  • Designed to offer an outdoor reset for optimized home heating
  • Easy control options
  • 95% AFUE efficiency
  • Convenient control options

Take Note

  • It’s costly

You can also buy cupboards to hide away your boilers and keep them safe outside HERE

ALSO SEE: Plastering Over Copper Pipes

Best External Gas Boiler

  • Rinnai Q-Series Condensing Boiler


This natural boiler will provide your home with good indoor heating.


  • Fairly simple to set up
  • Available in over 6 styles
  • Built with quality and sturdy stainless steel
  • Compact wall-mounted design saves space
  • Designed with optimal indoor heating in mind

Take Note

  • Fairly heavy


  • Rheem Tankless Natural Gas Water Heater


The Rheem tankless natural gas water heater offers value for the money spent on it.


  • Saves energy, up to 94%
  • It is much more affordable than several other boilers on this list
  • It is produced with a stainless-steel condensing heat exchanger
  • Electronic controls designed to increase energy efficiency and safety in your home

Take Note

  • You’ll need help setting it up in your home


  • Ecosmart Electric Tankless Water Heater


This is an affordable yet durable boiler that heats up your home really well. Plus, it’s peraps the cheapest boiler on here.


  • Price is less than $500
  • This electric water heaters is built to last
  • Very durable
  • Setup and cleaning is simple
  • Lifetime warranty

Take Note

  • It will help you save up to 60% on your water heating costs with its advanced technology

Leave a Comment