Slant-Fin Sentry Boilers

Slant-Fin Sentry Boiler Overview

The Slant/Fin Sentry is a gas hot water boiler with an efficiency of 84.4% AFUE. The unit’s thermal targeting technology is designed to save on fuel by monitoring heat demand. A thermal pre-purge option is also designed to conserve fuel. The unit features a display which shows the boiler water temperature and boiler control’s setting, and LED lights help monitor the system. The Sentry’s insulated jacket is designed to prevent heat loss and provide quiet operation.

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Consumer Reviews of Slant-Fin Sentry


  • Very Satisfied
  • Somewhat Satisfied
  • Neutral
  • Somewhat Unsatisfied
  • Very Unsatisfied
  • #3 of 7 Slant-Fin Boiler
  • 96.88% of customers recommended

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Slant-Fin Sentry Boiler Reviews

Showing 16-20 of 32 reviews

"Low Cost Boiler with Easy Installation"

5.0 rating
Very Satisfied

We had to replace the boiler in our home in Baltimore around the same time that we had to replace the water heater in our "winter home" in Texas, and I was absolutely blown away at the difference in the prices. In Texas, you can get a water heater for $500. When I walked into Home Depot to get a boiler this unit was literally the cheapest at nearly $1800 with tax. I couldn't imagine paying more than that, so we went with the cheapest option. That's usually a scary idea when it comes to home repairs because of the idea of you get what you pay for, but in this instance it all worked out. We replaced a 20 year old boiler and instantly noticed that this one works much better overall. The installation was easy (my husband and brother in law did it themselves in less than two hours) and we have no complaints about its reliability or output. I have noticed, however, that it seems to increase our gas usage. But gas is so cheap that it's hardly a real concern. In this case I'd say go ahead with this model and save some money compared to the more expensive models.

Baltimore, MD

"Best boiler money can buy!!!"

5.0 rating
Very Satisfied

The sentry boiler is the best boiler on the market that you can get for your money. This boiler was purchased originally as a replacement for an older boiler I had in my home. I wanted something that was easy to install and easy to replace parts if necessary. I liked that it's quiet and not an eye sore. So far boiler has keep house at 69 to 72 degrees with no trouble. Since owning this boiler my heating bills has went down by over 40%. I've owned this unit for about 10 years and haven't had to replace a thing. I would recommend this brand to any of my friends looking for a new one. I would even help them install it if needed it was seriously that easy. This sentry unit is Durable, Sturdy, High Quality, Easy to Install, Looks Great, Good Size & Weight, and Nice Design.


"Best hot water boiler heating system I have owned"

5.0 rating
Very Satisfied

I have owned this boiler for a little over two months now and I absolutely love it. First of all it has a very advanced design, that makes it look sleek and cool. The boiler is very easy to install even if you have low overhead clearance or low chimney connections. I installed it with the help of a friend and it did not take us very long. I really like the boiler because it saves me on energy cost, I assumed it would burn a lot of energy and considerably increase my utility bill but this was not the case. I have only had it for two months so I have not had to replace or repair it, however I do not think that is something I would have to do anytime soon. The boiler seems strong and durable but I will have to see how it looks in a years time. As of now I would buy this brand again and definitely recommend it to a friend. The boiler works well and has a lot of nice features on it.

Atlanta, GA

"The problem with cold winters and boilers"

4.0 rating
Somewhat Satisfied

My problem with my gas burner results in the protection system derived within the oil tank. I have a big house so I needed a high powered boiler. Unfortunately, the oil tank leaves 30 gallons of gas cut off from the burner as a fail safe to keep the pipes from busting. This means that if I purchase 50 gallons of gas, I only get to use 20 gallons of it because 30 is held in reserve. I'm only 1 person, I shouldn't have to buy a hundred gallons of gas just to take a shower a day. Even though this problem technically stems from the oil tank and not the burner, I still think there should be a way for newer models to override the failsafe. Aside from that the boiler works perfectly fine. As long as I keep a lot of oil in it never has any issues.

Bay Shore, NY

"Highly Recommend Sentry Boilers"

5.0 rating
Very Satisfied

My boyfriend and I moved into a Victorian house and quickly got frustrated with how little heat we had. In addition to a variety of other issues, tons of noise and water leaking, we discovered that the boiler was over fifty years old. After we made this discovery, we made the decision to invest in a new boiler. We researched a few different boilers, but eventually decided on the Sentry Slantfin. We were worried that this particular model was slightly too low in BTU output, but over all we have been extremely satisfied with the quality of this boiler. We have heat right away and have had absolutely no issues with the product. It fit within our budget and we see it as a great deal if it lasts as long as the ancient boiler we removed and replaced! So far we have had this boiler for a little over a year and would highly recommend it to anyone looking for a boiler with a house on the smaller side. Our only complaint is that it is slightly on the noisy side, but it is nothing too noticeable.

Denver, CO

Other Sentry Reviews

Based on comments from online HVAC forums, the Sentry is regarded as a good unit. Consumers on and had problems with their Sentry boilers not heating correctly that were both determined to be caused by a circulator and not the unit itself.

Sentry Warranty

The warranty for the Slant/Fin Sentry boiler is comprised of the following:

  • 1-year warranty on parts
  • Lifetime limited warranty on cast iron sections, prorated after the 10th year

Labor and shipping costs are not covered by the warranty.

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