mobilehomerepair.com

As luck would have it, my old Coleman furnace decided it had enough here and cracked the heat exchanger. On the other side, I got my hands on a Nordyne. I was told the unit was 2-3 years old. It looks brand new. The question I have is this.
The coleman was rated at 95k btu in, 72k btu out.
The nordyne is 77k in, 62k out.

The Coleman is atleast 20 years old. When it was installed into my house, it heated the whole house. Over the last 20 years, one room was made into a utility room, and is no longer heated. I also searched around Nordynes website and other that Btu ratings, I dont see a difference between their 77 and 90 furnaces.

Can this 77 be converted to a 90?

Its a Nordyne M1MB 077A AW.

The 90 is a M1MB 090.

Thanks for your time helping all of us out!

I would not recommend any home owner to try and over fire a unit. It might be able to be done but a professional will have to see if there are any differences in capacity of the heat exchangers and usually there are. What I am saying to you is NO unless you have a professional look at the furnace,check the heat exchanger part numbers,verify the size of the orifice and do the conversion if possible.

From my past experience most furnaces will not have a large enough heat exchanger to allow it to be over fired and if converted they usually burn out quickly.

The new unit you have access to will probably work just fine without any increase in output needed. Most original equipment is a bit to larger to start with so the size of the new one will probably take care of your heating needs without any modifications.

Thanks for the detailed and quick reply. I will be having a pro install it. Its kind of intimidating to me. I was thinking that you couldnt overfire it either, but I cant see the furnace having a bigger heat exchanger in it since the one it has fills the entire cabinet.

Thanks again for your help!

Mike

Just for fun I looked up the heat exchanger part numbers.

The M1MB 77 part number is 903415

The M1MB 90 part number is 903416

The exact description of the heat exchangers is also is a bit different which means the they do have different size heat exchangers so a conversion would not be economically possible.

I hope this answer is a little more clear and accurate than my last. I was not trying to hood wink you but I felt I needed to look it up to clarify my previous answer.

Sounds like proof to me. I called a Nordyne dealer after I read your reply. Said it couldnt be done and I should buy a new furnace from, who else, them.

No hood wink felt here

Thanks a million again!!

Take care and best wishes,
Robert

Would you guys happen to carry the acoil cabinet for this furnace? Along with the matching door? Furnace face is white.

Its a Nordyne M1MB 077A AW.

Hi,

Most likely, will check Monday and let you know.


Thanks,
Robert

Hi,

A-Coil Cabinet w/door # 911969A @ $149 + $45 shipping .


If interested, please call toll free to 1-877-263-7860 between

9AM and 5PM CST Mon - Fri and charge to Visa or Mastercard or

have a PayPal Invoice sent to you for payment.


If outside the U.S., let me know for added info.


Thanks.



Take care and best wishes,
Robert