Low heat problem

[daniel@procarpet]

I have a Prochem Legend XL. The temperature doesn't seem to be right. In fact, the temperature has been off for a while. What temp should my machine realistically hold at while cleaning carpet with a 6 flow wand at 300 psi? After doing a fairly large job today in 70 degree weather, I checked the temp on the mahcine and it was at 140. When I keyed the wand, the temp jumped up to 230. Within 10 seconds after keying the wand and holding the trigger the temp was back to 140. I feel my machine should hold at least 180 to 200.

I checked the temperature relief valve the other day and it was slightly leaking as soon as the machine was turned on. After replacing it, I thought my problems would be solved. There is a chance the new valve could be defective but I highly doubt it. The heat bypass valve appears to be in good order, but I will do another inspection of it. Again shouldn't my machine hold in a general range? Whats up with the sudden temperature spikes and declines? After prespraying and getting the machine hot, the temperature drops to 140-150 as soon as I clean half a room. This machine should hold at 200 in a warm climate like mine shouldn't it.

 

[Doug D]

check equipment repair room under slide ins. There was a post in there about heat exchange but it was for a prochem peak if I remember right. That may be the problem. may need to clean out the heat exchange? just a thought.

 

[The Magician]

Descale and clean the orffice/ filters on front ot the machine.

 

[Able 1]

How many hours do you have on your TM? I would clean the heat exchangers IMO. Pretty easy to tell you the truth. I would say the first time you should clean them out is 750 hours after that every 500 hours.. I waited way too long for mine.

Your heat exchanger:

 

[packfancjh]

Is the machine dumping into the waste tank during operation? Have you checked the thermal valve?

 

[davep105]

Sounds like the water isn't circulating, maybe something is clogged. I had a Prochem cub XL that would do the same thing. There was a filter in the water box that would get clogged up and would not alow the water to circulate and when I pulled the wand trigger the heat would spike up high. I remeber on time it blew the solution line right off the front of the machine, thank god no one was in front of the machine.

 

[SuperFly]

I have a Prochem Legend XL. The temperature doesn't seem to be right. In fact, the temperature has been off for a while. What temp should my machine realistically hold at while cleaning carpet with a 6 flow wand at 300 psi? After doing a fairly large job today in 70 degree weather, I checked the temp on the mahcine and it was at 140. When I keyed the wand, the temp jumped up to 230. Within 10 seconds after keying the wand and holding the trigger the temp was back to 140. I feel my machine should hold at least 180 to 200.

I checked the temperature relief valve the other day and it was slightly leaking as soon as the machine was turned on. After replacing it, I thought my problems would be solved. There is a chance the new valve could be defective but I highly doubt it. The heat bypass valve appears to be in good order, but I will do another inspection of it. Again shouldn't my machine hold in a general range? Whats up with the sudden temperature spikes and declines? After prespraying and getting the machine hot, the temperature drops to 140-150 as soon as I clean half a room. This machine should hold at 200 in a warm climate like mine shouldn't it.

You could have a malfunctioning thermostat..! Recalibrate..
Air pockets in HE'er..! bleed them/descale as said above..
Ck for any exhaust leaks..!
Is there a HE dema solenoid on your Legend?
It might be stuck open in dump mode..! Or a loose wire..!

 

[Mike Draper]

1 gallon hydrochloric acid at a brick store $5.50 / Put 2 gallons of water in a bucket then half gallon of the acid. Run this through the hx for 4 minutes. This should clean out any scale buildup you might have.

 

[daniel@procarpet]

My supplier told me I should never have to descale my truckmount as long as I am using water from the city I live in. Memphis does not have hard water. So I doubt it is the hx. No one really answered my question. What temp should a legend XL maintain using a 6 flow wand at 300 psi in 70 degree weather? I am taking my machine in Monday morning and I will post the results I get.

 

[Glynn]

From what Iv'e heard a Legend can only hold up a max of 180f.

 

[steve r]

just helped a freind diagnose his 405 performer similar problem. micro switch behind the thermostat.his goes bad yearly i think.just unplug it and see if you get high heat but dont run it too long that way.

 

[daniel@procarpet]

Well I took my machine in and had it checked out. There are only two places water can leak or be dumped into the waste tank which are the temperature relief valve on the water box and the heat bypass valve. Both of these were in good order. The diagnosis explained to me was the heat exchangers were simply dirty or very dirty for that matter. When the machine is just running with no water being keyed the temp will heat up. The hot water should be pumped into the water box until that temp reaches 145 and then it should bleed off into the waste tank. As soon as the wand was triggered the temp would almost instantly drop to 140 or below. The water in the water box should be so hot you can't put your hand into it (145). It was only slightly warm.

I could not believe how dirty the exchangers were. We used a compressed air hose to blow the heat exchangers out. A black cloud of smoke must have went thirty feet in the air. After getting as much soot off the exchangers we sprayed coil cleaner on them and let the cleaner work for about 15 minutes and then rinsed them off. You may be asking how the exchangers got so dirty. Well I have had foam suck into the blower several times when cleaning tile. The blower exhaust passes over the exchangers and eventually the build up began. Now that the exchangers are clean and able to breathe, my machine easily maintains 220-230 all day long. Note it is 70 degrees here. I feel kinda stupid for waiting so long to have this work done. I have been cleaning with 120 degree water for the past 2 years. I can clean so much easier now. Now that the machine is running HOT, I am affraid that my solution lines will break down twice as fast. Next order for me is to set up my Everest with the 2.5 inch hose I ordered and get a new wand. I can't wait to see how it performs.

 

[Mike Draper]

it's a good feeling when your machine is running 100%. 8)

 

[Art Kelley]

Buy a new solution line.