I have a moen kitchen faucet model 87480. When using the sprayer the flow/pressure is great but the faucet stream of water doesn't stop or slow at all. Is this normal or an installation/product problem?

Not normal. When you open the sprayer, the flow of water out the sprayer closes a valve inside the body of the faucet that stops the water from coming out the spout. That valve needs to be replaced. Could be that some trash or debris is caught in it and cleaning will fix. Otherwise replace.

Moen is warranted for life. Call 1-800 BUY-MOEN for replacement part.

Not normal. When you open the sprayer, the flow of water out the sprayer closes a valve inside the body of the faucet that stops the water from coming out the spout. That valve needs to be replaced. Could be that some trash or debris is caught in it and cleaning will fix. Otherwise replace.

Moen is warranted for life. Call 1-800 BUY-MOEN for replacement part.

Thanks much!