#### Hybrid View

1. Professional Member
Join Date
Oct 2003
Location
Minnesota
Posts
162
Post Likes
Here's the deal I have a customer that is heating his garage with a natural gas hanging unit heater. He is very concerned about his gas bill this last month. How can I find out how much gas this unit would burn in a 24hr. period.

unit heater 60mbh input,
48mbh output,
1.1137 gas pressure factor,
1.0058 BTU factor

Any help with this would be great.

Thanks, helgy

2. Professional Member
Join Date
Feb 2004
Posts
2,789
Post Likes
clock the input first. test hand value X movement X time
sample 1/2 x 19/10 x 60/1== 57342 you mentioned this is not @ 7''w.c but 1.1137 lbs?? If this is so than you must use multiplier and that depends upon area. We use 14.95 here 14.95 + 1.1137 divided by 14.95= 1.07 x57342=61356
I think I got that right. Going from memory ands its been a while. Make sure you check test hand and count number of divisions (some have 8) 1/2 is test hand value 19/10 is the numer of divisions hand went in 60 seconds thus 60/1

3. Member
Join Date
Jan 2005
Location
Gilroy, Calif
Posts
188
Post Likes
Hi mike. I was just reading this and trying to decipher a response. pounds pressure! must be a big garage.

4. Professional Member
Join Date
Feb 2004
Posts
2,789
Post Likes
Hi Gary. How close was I?

5. Member
Join Date
Jan 2005
Location
Gilroy, Calif
Posts
188
Post Likes
Not sure mike. I'm going to look that one up in the morning. The pounds pressure is throwing me alittle. Whats up with the mbh rating? That stands for million pounds an hour, doesn't it? Must be a RRRRRREEEEEEEally big garage.
The clocking formula is right on target.

[Edited by gje1 on 01-31-2005 at 11:51 PM]

6. Professional Member
Join Date
Oct 2003
Location
Minnesota
Posts
162
Post Likes
sorry guys I might have a few things wrong with this equation. First it's a 60,000BTU unit heater. Next, it is a 2 lb. gas meter w/ a maxitrol inside the house stepping it down to 8"wc. Hope this clears thing up.
Thanks for the help.

helgy

7. Professional Member
Join Date
Feb 2004
Posts
2,789
Post Likes
OK now make that last multilier 1.13 instead of 1.07

8. Professional Member
Join Date
Feb 2004
Location
Central Kansas
Posts
1,145
Post Likes
Careful, Mike: remember, gas guys supposedly can't even tie their shoes without supervision and you're talking algebraic formulas now (lol)! One also would have to factor in run time, determined by heating degree day, heat loss of the structure, etc. to get all the data I think they are after. That's like asking how many gallons of gas my car will use on an any given day. You tell me how many miles I'm going to be driving, then I can determine fuel usage. Greg

9. Professional Member
Join Date
Feb 2004
Posts
2,789
Post Likes
Point well taken. However my part stopped at btuh rate. Now he can sit there with a stop watch and time the burner on cycles.

10. Member
Join Date
Jan 2005
Location
Gilroy, Calif
Posts
188
Post Likes
Now for the rest of the story. The original question was the cost for a 24 hour period for this heater. So, once you have the input per hour from your clocking. You'll need a current bill from your local utility company to find out the cost of a therm. Should be on the bill as therms used at unit cost of....... You can use this to calculate at 24 hour period. An easier way is. 100,000 btu = 1 therm and if one therm is equal to let say \$1.41. Well you get the idea.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•

## Related Forums

The place where Electrical professionals meet.