Mash tun not hot enough

Get help and insight.
Post Reply
don.fief@comcast.net
Posts: 32
Joined: Thu Feb 23, 2012 1:26 pm
Bot?: No

Mash tun not hot enough

Post by don.fief@comcast.net »

I had a successful brew day after changing my burned out element, but with some flaws. My buddy made the same recipe that I did, but did not use the RIMS system. He went old school. At the end of the mash, his wort seemed sweeter, and more malty. At the end of the boil his had a higher O.G. While mashing, I was watching the temp in the Mash tun compared to the RIMS. There was a significant difference. I was trying to mash at 150, but the tun varied from 140 - 145, sometimes even lower. (I am not connected to the BCS now to look at the actual data) I used a stainless kettle from Blichman for the tun. Things got better when I wrapped it in a blanket, even the top. How much difference in temp do you guys see from the tube to the tun? How insulated is your tun? I am considering using my old ice chest tun for the process, just drilling the lid for the return from the tube...

Don
JonW
Site Admin
Posts: 1726
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Mash tun not hot enough

Post by JonW »

There's a lot of things that come into play here. What was the ambient temperature? Was the mash tun pre-heated with your strike water to hit your original strike temp or did it drop considerably right at mash in? What kind of flow rate and heat rise are you getting out of your RIMS tube? Seems like maybe you're not moving enough wort through it.

I direct fire my Blichman MLT and don't insulate it at all. I heat my strike water in the MLT so that the kettle, pumps and plumbing are all up to temperature before mashing in. When I mash in, the only temp loss is due to the grain temp. I also do continuous recirculation at a pretty good flow rate and let the burner fire back on as needed to maintain the temp. If your RIMS tube is working properly, I don't see why it couldn't maintain the temperature.
ksl177
Posts: 37
Joined: Mon Feb 27, 2012 1:22 am
Bot?: No

Re: Mash tun not hot enough

Post by ksl177 »

+1 to what Jon said.

Additionally, Rice Hulls for the win and make sure your water to grain ratio is above 1.5:1 (closer to 2.5 for Wheat beers) Every time I've had issues with bad mash efficiency I can trace it back to fact I forgot to put rice hulls in the mash, or my water to grain ratio was too low.
don.fief@comcast.net
Posts: 32
Joined: Thu Feb 23, 2012 1:26 pm
Bot?: No

Re: Mash tun not hot enough

Post by don.fief@comcast.net »

I think I hit my strike temp pretty well, but then, I was only going for a 90 degree acid rest... The ambient temp was about 65 degrees, and a slight breeze. I think that had a lot to do with it. My tube was not up to heat, but did maintain the acid protien rests well. Then I had a LONG protien rest while I ran to Home Depot to get a new heating element... Then it had a hard time with the actual mash.

As for the flow, this is my second use of the RIMS system, with the first being stuck over and over... I added rice huls to it this time, and no stuck mash, but maybe I was paranoid about how much flow to have... I wanted to restrict it a bit to make sure it heated, but didn't want ot too slow, and then again, was afraid if I flowed too much, it would stick again, or not heat as it passed over the element...
don.fief@comcast.net
Posts: 32
Joined: Thu Feb 23, 2012 1:26 pm
Bot?: No

Re: Mash tun not hot enough

Post by don.fief@comcast.net »

JonW wrote:There's a lot of things that come into play here. What was the ambient temperature? Was the mash tun pre-heated with your strike water to hit your original strike temp or did it drop considerably right at mash in? What kind of flow rate and heat rise are you getting out of your RIMS tube? Seems like maybe you're not moving enough wort through it.

I direct fire my Blichman MLT and don't insulate it at all. I heat my strike water in the MLT so that the kettle, pumps and plumbing are all up to temperature before mashing in. When I mash in, the only temp loss is due to the grain temp. I also do continuous recirculation at a pretty good flow rate and let the burner fire back on as needed to maintain the temp. If your RIMS tube is working properly, I don't see why it couldn't maintain the temperature.
I just re-read your post, and realized that you are using both a burner under your MLT and a RIMS tube... Do you control your burner yourself, or is it hooked to your BCS also?
JonW
Site Admin
Posts: 1726
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Mash tun not hot enough

Post by JonW »

don.fief@comcast.net wrote:
JonW wrote:There's a lot of things that come into play here. What was the ambient temperature? Was the mash tun pre-heated with your strike water to hit your original strike temp or did it drop considerably right at mash in? What kind of flow rate and heat rise are you getting out of your RIMS tube? Seems like maybe you're not moving enough wort through it.

I direct fire my Blichman MLT and don't insulate it at all. I heat my strike water in the MLT so that the kettle, pumps and plumbing are all up to temperature before mashing in. When I mash in, the only temp loss is due to the grain temp. I also do continuous recirculation at a pretty good flow rate and let the burner fire back on as needed to maintain the temp. If your RIMS tube is working properly, I don't see why it couldn't maintain the temperature.
I just re-read your post, and realized that you are using both a burner under your MLT and a RIMS tube... Do you control your burner yourself, or is it hooked to your BCS also?
I do not use a RIMS tube. As I said above, I do continuous recirculation and let the burner fire back on as needed to maintain the temp. I turn the flame on the burner down so it is a lighter direct heat than how I have it during heating the strike water. Yes, it is all directly monitored and controlled by the BCS.
Post Reply