Bigger Blower on Hotblast

[Ryan18327]

I have a hotblast 1557 that I have been using to heat my house for a year since we bought the place. This year it seemed to working nowhere near as well as last year so I decided to change out the blower and re-do the ducts (return was too small and the supply was small as well.

I installed a regular furnace blower (1/3 HP and it says it is rated for 2-3 tons of air movement). I havent hooked in the return just yet as I'm waiting on a part, but I decided to try it out just my allowing the blower to use the air from my basement...

I got the fire going but once the blower kicked on it seems the firebox cools off really quickly and the supply air cools down fast as well... Could it be the blower is too big? It isnt moving much more CFM than the dual motors on before... Also, when I installed it, I did not mount it directly centered on the back of the stove. Its slightly offset to one side, could the airflow in the chamber be messed up because of this?

I had to cut open the back of the stove frame to accommodate the bigger blower opening but patched it up well after.

Image is attached (wires are exposed because I was testing the different fan speeds.

 

[cornfused]

Is your blower wired into a temperature sensing fan control or just direct wired to run constantly?? A constant run will over cool the fire box.

 

[Ryan18327]

Is your blower wired into a temperature sensing fan control or just direct wired to run constantly?? A constant run will over cool the fire box.

It is wired to a honeywell fan/limit switch. Fan doesn't kick on until 130 and off again when it cools to 100

 

[Ryan18327]

I was thinking it might be because the fan is kind of offset to one side and is creating turbulence so to speak in the air chamber. But I have seen people running this system with just 1 of the double blowers before and they said it worked good... I guess I have a better feel when I can hook the return back up. I'll try centering the fan too since it wont take long.

 

[cantoo]

I ran a regular furnace blower on mine for years and never had an issue. Mine is mounted on the one side, it shouldn't make any difference.

 

[HadleyPA]

Mine is not a hotblast but is basically the same thing. It's a Johnson energy systems. I put a regular size furnace blower on mine as well. I have to run mine on the lowest speed and even at that I had to put a screw in each air duct out the top because they wanted to blow off. I run the limit switch to kick on at 150 and off at 100 and have had good results with it like that. Also, I do not have a return on mine, just let it suck air from the basement, however, I only tied 1 of the 8" outlets into the furnace duct and just put a 90 coming out of the other with a plate on it blocking about 75% of air coming from that one. That allowed some air from blower to stay in basement and also forced more to go through into ductwork and helps keep the blower from kicking off so quick. Been this way for about 15 years now and so far so good.