Correct sizing of unit for furnace

[mickalene calavano]

Hello, I recently received a heat load form for my house and the entire house has a heating load of 52362. What would be the appropriate btus required for the furnace? House is in Jersey. Well insulated.

[Scott Patterson]

Hello, I recently received a heat load form for my house and the entire house has a heating load of 52362. What would be the appropriate btus required for the furnace? House is in Jersey. Well insulated.

You will most likely need to contact the folks that did the calculation on your home for you. They should be able to tell you exactly what you need to know. Some variables to take into consideration would be the number of heating days vs. cooling days (your location), design of the home and the type of system you are looking to install.

[Jim Robinson]

I have to admit I have no idea what that number means.

[Jack Feldmann]

I thought it was a zip code. I have no idea either, but then I don't do energy audits or heat load calculations.

[James Duffin]

Here is my take based on limited information...

The design temperatures for NJ are 0 degrees for heating and 95 degrees for cooling. Since you are talking about heating only one that matters is the 0 degrees for heating and that was taken into consideration when the 52362 figure was obtained. Since the calculated heat loss for the house is 52362 BTU's per hour at 0 degrees outside you would need a furnace that can replace the heat loss per hour. That would be the next standard size unit your manufacture of choice makes. It might be a 60,000 or 75,000. If you over-size too much the unit is will short cycle, not provide even heat, and it will cause the equipment to wear out faster.

[mickalene calavano]

Thank-you Mr Duffin: you have confirmed twice now the issues I have been having with my HVAC contractor. Not only for cooling, but, also for the heatin system. I had no idea I needed to know so much from a consumer standpoint before purchasing a HVAC system. You are truly helping the public with the information you provide. I wish I had done more research prior to hiring a HVAC contractor. I have learned a lot, and honestly, more then I need to know about HVAC at this point. Thank-you again. Where are you located? And better yet, can I use you as an Expert Witness in a court of law? thanks
Jersey




Here is my take based on limited information...

The design temperatures for NJ are 0 degrees for heating and 95 degrees for cooling. Since you are talking about heating only one that matters is the 0 degrees for heating and that was taken into consideration when the 52362 figure was obtained. Since the calculated heat loss for the house is 52362 BTU's per hour at 0 degrees outside you would need a furnace that can replace the heat loss per hour. That would be the next standard size unit your manufacture of choice makes. It might be a 60,000 or 75,000. If you over-size too much the unit is will short cycle, not provide even heat, and it will cause the equipment to wear out faster.

[James Duffin]

I am in NC so I doubt NJ would care about what I have to say. You should be able to find a HI or HVAC contractor to help you with your problem in NJ. This is a all standard stuff so I am not blazing any trails with my info.

Go to this website and I'm sure you will find a HVAC contractor in NJ who can help you with your cause. HVAC-Talk: Heating, Air & Refrigeration Discussion - Powered by vBulletin (http://hvac-talk.com/vbb/)

[Zibby Bujno]

Hello, I recently received a heat load form for my house and the entire house has a heating load of 52362. What would be the appropriate btus required for the furnace? House is in Jersey. Well insulated.
If that's a 52,362 BTUH then add 10% safety factor and round up to nearest whole number
52362 * 1.1 ~60,000BTU equipment required

[Rod Butler]

If that's a 52,362 BTUH then add 10% safety factor and round up to nearest whole number
52362 * 1.1 ~60,000BTU equipment required

So is the furnace gas fired or electric?

If it is gas (or not) are you going to have a DX AC unit installed as well?

If it is natural gas remember to take into account the efficiency of the of the unit which reduces the capacity from the name plate rating. If you need 60,000 BTUH and plan on using an 80% furnace you will need a furnace rated at 75,000 BTUH. (60,000/0.80).

If you are going to add air conditioning you may default to a unit size that will provide enough air flow for the cooling.

HTH :eek: