Allied super hot vs Laars JV?

John McArthur_2

We have a town home complex that we have been using JVs up to this point but am considering switching to something else. The job will not support a mod/con, unfortunately, so I am considering the Allied. I only found 1 post in the archive that was less than impressive.

My biggest issue with the JV is the propensity to short cycle at low loads. I know the Allied is also a low mass boiler also and likely would not solve that issue.

My best option may be a cast iron unit. The job is P/S with radiant floors (high mass), IDWH, and a small snow melt HX. I have been using the Taco RMB for mixing and am pretty happy with it. The job is also power vented via a Fields SWG.

Any opinions on Allied or thoughts on whether I should go with a CI boiler to limit the short cycling would be appreciated.

ALH_4

cast iron

I like the cast iron idea.

FWIW, the Viessmann ECDS wet leg cast iron boilers are pretty inexpensive, and have a very small footprint, if that would help.

Leo G_99

Mr. McArthur

Live about 1.5 miles from where the Allied is built. Love them! They may be steel, but industrial grade and 2" waterways, so there is quite a bit of volume inside of them. I usually hook them up with a tekmar or the aforementioned RMB, and they have worked wonderfully! I also mostly use their electric boilers also. I find the wiring to be too simple, no trying to wire inside a very crowded terminal box, and if 4 zones or less, just plug into the zone controller.

I have serviced some of these boilers that are over 40 years old. They are supplying convection baseboard, and are still running quite effeciently.

As you can see, I am a very big fan of these boilers and have no hesitation using or recommending them!!!!

Leo G

John McArthur_2

Leo,

Thanks. That's good to hear. I encounter a lot of them through service calls (though not boiler related).

I installed a few several years ago and had some nagging problems with the flame roll out switches tripping due to excess heat in the combustion chamber. I understand they got the problems worked out.

I am mostly concerned about short cycling. I know that short of modulation, it will be difficult to manage given the huge variance in heat loads I see. We had temps in the 40's about three days ago and had -35 last night. We saw -42 last year. At 7'000' altitude, deration is also a factor.

The 2" waterways is the reason I started to consider the Allied. I generally like a CI or mod/con but some jobs the lighter weight and lower price of the copper tube boilers have swayed me.