How do I get a copy of the acceptance letter for installment payments the irs sent me for the tax year 2014

You must get it from the IRS.

thank you very much for the detailed way to contact the irs ...

Installment agreement information : 

https://www.irs.gov/individuals/payment-plans-installment-agreements

If you want to talk to someone at the IRS, you could try the following. (Thanks to SuperUser epo39b for figuring out most of this sequence.)

Call the IRS at 1-800-829-1040 weekdays from 7am to 7pm local time.

At the first prompt press 1 for English.

At the next menu press 2 for questions about your personal income taxes.

At the next menu press 1 for questions about a form you have already submitted, your tax history, or payment.

At the next menu press 3 for all other questions about your tax history or payment.

At the next menu press 2 for all other questions about your tax history or payment.

There will be a brief pause. When it asks you to enter your SSN or EIN to access your account information, don't enter anything. After it asks twice, you will get another menu. Press 2 for personal or individual tax questions.

It will then put you in the queue for a live agent, and tell you the estimated wait time.

No longer press 4, instead press 3 for all other questions about your tax history or payment.

Well that answer is 2 years old... not surprising it is out of date.

It seems to be hit or miss with the customer service rep you get.  Some insist that you need the IRS transcript and other know what you need and figure out a way to make it happen.  One IRS agent told me they don't keep these letters and had to create a new one to fax to me.  Another told me they don't do that.  It's a very frustrating process thus far.

Do you have a payment plan in place ?  

<a rel="nofollow" target="_blank" href="https://www.irs.gov/individuals/reviewing-and-changing-your-payment-agreement">https://www.irs.gov/individuals/reviewing-and-changing-your-payment-agreement</a>

Do you need to know your current balance ?

<a rel="nofollow" target="_blank" href="https://www.irs.gov/payments/view-your-tax-account">https://www.irs.gov/payments/view-your-tax-account</a>

I have a payment plan in place.  The mortgage company insists on a letter with the installment agreement.  I've spent about 5.5 hours on the phone with the IRS trying to make this happen and I just can't seem to.  Three different people I've spoken with have told me they could do it, set it up to fax and the faxes never come in.  I've tried a different fax line each time.  Every other time I call, no one will help me.  They tell me that it's not possible to get this letter.  Not really sure what to do now.

See if you can get anything online at the links I posted above ... or  find a local office and see a human in person.

If you're an individual taxpayer, you can use this tool (link provided by @Critter#2 ) to view:

• Your payoff amount, updated for the current calendar day
• The balance for each tax year for which you owe
• Up to 18 months of your payment history
• Key information from your current tax year return as originally filed.

If that's not good enough for your mortgage company, go elsewhere.

test

Were you ever able to get this installment plan agreement letter to submit to the lender?  I'm on the phone with the irs right now, of course on hold, hope I can get somewhere.  TIA

After dozens of phone calls, I was not.  Make an appointment and go to your local IRS office and you'll be able to pick it up there.  Hope that helps.