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State Proline XE Combi Boiler

state proline xe combi

This is my new State Proline XE Combi boiler. It's unbelievable that it heats my entire home and provides all the needed domestic hot water for cleaning and bathing. Copyright 2018 Tim Carter

State Proline XE Combi Boiler - Small Workhorse

The first week of December I removed a clunky cast-iron boiler at my home and replaced it with a sleek and compact State Proline XE Combi boiler.

The difference is simply amazing.

My State Proline XE Combi boiler is magic in a box. CLICK HERE to discover more about it.

WATCH ME show off my new State Combi boiler in this video:

How Does the Size Compare to the Old Cast Iron Boiler?

I would say the new State Proline XE Combi Boiler is less than half the size of the old Peerless cast-iron boiler.

peerless cast iron boiler

This is my old boiler after we took it outdoors. It was about 28 inches wide, 32 inches high and about 34 inches deep. I can't believe I didn't take a great photo of it still in place! Copyright 2018 Tim Carter

Is the New Combi a Modulating Boiler?

Yes, my new boiler only creates as much flame is as needed to heat the demand. My old boiler was either OFF or running at FULL BLAST. A modulating boiler uses much less fuel.

How Efficient is the State Proline XE Combi boiler?

It's got a 95% AFUE rating. That's about as high as you can get.

state proline xe combi

state proline xe combi

Here's the State Proline XE Combi boiler with my domestic hot water manifold to the right. Each one of those PEX lines feeds hot water to a faucet in the house. The combi boiler can make hot water as long as there's propane in the outdoor tank. Copyright 2018 Tim Carter

state proline xe combi

These are the vent and incoming air lines. The gray pipe is schedule 80 and is the outgoing vent. The white pipe is incoming fresh combustion air. Copyright 2018 Tim Carter

state proline xe combi

This is the nameplate you'll see on your new State Proline XE Combi boiler. Copyright 2018 Tim Carter





State Proline XE Combi Boiler - Small But Mighty!
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State Proline XE Combi Boiler - Small But Mighty!
My new State Proline XE Combi boiler is magnificent. it hangs on the wall and heats my entire home. It provides all the hot water for cleaning and bathing too.
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19 Responses to State Proline XE Combi Boiler

  1. I really got exited when I saw this new product highlighted by you Tim.
    My daughter has one of the large boilers like you did have. Only difference is she has the water lines in her floor! Would the Combi- Boiler work with this kind of distribution system, and would it work with natural gas?

    • It makes no difference if the water lines are in the floor or go to radiators. We have in-floor lines in the basement, but radiators in the two upper floors.

      Had I built the home, I would have put the heating in ALL the floors.

      Yes, the boilers work for propane OR natural gas. You need to order the RIGHT ONE or get the conversion kit.

  2. Can one assume that this new boiler is only worthwhile if your old one is over the hill?
    How much more efficient is this unit so one can do a cost benefit analysis

  3. Tim,

    How much do these boilers typically cost? In the 2 or 3 years I am going to need hot water tank and a boiler replacement. I have a plummer friend who can do the install but I will need to purchase the unit so that is why I ask. I expect to need the lowest btu version.

  4. I have a Navien Combi Unit and I love it. I had it installed four years ago and have never had a problem. My home was built in 1952 and this unit replaced the original boiler, which was huge and looked like the old incinerators back in the day.
    I highly recommend them!

  5. Hi Tim, I have a Peerless PF-110 95% mod-con boiler, about 3 years old, which I assume is similar. Can you explain if these are similar and what differences may be for 95% mod-con boilers? We have in-floor radiant on 3 levels and an indirect water heater so we do not use the boiler for DHW. I expect (well, hope) these last a long time!

    • I think all you have to do is go to each website and compare the specs. No need for me to go do that for you, right? Use the link above in my column to get to specs for my combi. Then go to the Peerless site.

  6. I have a rinnai heater. there is a feature I like. I can run the electricity part of the unit with a computer UPS in a power outage. I see that you have many zones of pumps. If these are the newest you are all set, they have better pumping efficiency and quite possibly will run on the UPS. No need for a big gas generator, (depending on battery size). during outages

  7. We were about to install a Rinnai heater about 5 years ago until I discovered there is constant need to flush the heating coils of scale and the propane line needed to be larger and plumbing rerouted. Added another $1500 to the project. By constant I mean annually. What are the requirements of the new heaters? Tank systems only require replacing the sacrificial rod every five years or so.

  8. Tim, a while back you wrote an article comparing the costs of tank water heaters vs tankless heaters. It was determined the amount of gas saved was very small plus looking at the higher cost and maintenance of tankless was a losing proposition. I have a Weil Mclain boiler 85% efficiency that used the grey vent pipe which was recalled. Took 2 years to find an installer to replace with double wall stainless steel. No one wanted the liability of replacement. When the grey pipe was removed some sections disintegrated. With combination units seems like boiler firing on alot more than just a heating unit which drastically reduces longevity of unit? Comments.

    • Yes. Use the search engine here on my site and read ALL of my tankless heater columns.

      My stance for years has been don't buy one if your motivation is to have INSTANT savings. You only SAVE money after you recapture all the extra money you spent on the device plus extra installation costs. It's all in my past columns.

      In my case here, I needed a new boiler and was tired of having 200 gallons of heated water in tanks wasting energy. So since I was already installing a new boiler, I might as well get one that could act as a domestic water heater.

      That's different motivation than just switching out a standard storage-tank water heater with a tankless one.

  9. Hi Tim,
    Merry Christmas! How noisy is your system? We live in a townhome. Our boiler and water heater are located on the second floor in our storage space. There is no insulation in the wall between the storage space and the living area. The current set up is very quiet. I want the new system to be just as quiet.

    • The machine itself is very quiet. The exhaust outdoors when the boiler is running full tilt gets your attention.

      Bottom Line: I can live with any noise that creeps back indoors to save BIG MONEY on propane. I can already tell my propane bill is going to go down like the stock market did in the fall of 2018!

  10. Supplyhouse has 36 different makes & models of high-efficiency boilers. How did you decide on the Proline?

    Also, why do you run a PEX line to each hot water faucet instead of just connecting to the pipe from your old hot water heater?


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