One more thing to consider...
Your inquiry was for "low income" home owners, and you mentioned the $44,700 dollar-value threshold. If what you're looking for is the number of households with income below a certain threshold, the table I mentioned (B25118) should work.
According to HUD, the "low income" threshold in 2008 for a family* of 3 was 44,300 and in 2014 was 46,000. (See:
www.huduser.gov/.../FY08_StateIncomeLimits.pdf for 2008 thresholds and
www.huduser.gov/.../State_Incomelimits_Report.pdf for 2014 thresholds. The US values are at the bottom of each report.)
If, instead, you are looking for "low income" defined by ratio of income to poverty level, then you will need to use the ACS microdata. The easiest way to do that is to use the IPUMS system
usa.ipums.org/.../index.shtml. You will need a log-in, but it's free. The IPUMS "Analyze Data Online" tool you to query the microdata to create any crosstabulation you might need.
Feel free to send me a direct message if you want to discuss this further.
Good luck!
*HUD thresholds are for family income, while ACS published tables are for household income. It sounds like your predecessor used household income, but that might not be the most precise option. You may want to use the IPUMS system to get family data -- again, send me a direct message and we can discuss the nuances further.