Ruud Pressure Switches.

[skr0oface]

Hi, any help would be great..

ok so I was at this house earlier with a Ruud Hi efficient. start up furnace.. cb blower runs for 30 seconds then shuts off.. The condensate line coming off the bottom of the termination, was kinked badly in 2 spots. The furnace was running like this for 2 winters now.

After rolling the hose to get the kinks out, I got the furnace to fire up 3 times but not consecutively. I had condensate coming out the drain line to the sewer. Combustion Blower was making a slight slight gargle. barely noticeble. I was stumpt. cb blower is a bugger to remove..

Sorry no pics or model number. This is an upflow, Ruud Hi Efficient from 2003. The Hi and Lo pressure switches are both housed in a metal case. I've installed newer Hi efficients and noticed the new switches are housed in plastic.

Anybody else have trouble with these pressure switches before?? Im currently unemployed.. furnace is under warranty from the company i was previously with. they gave a good friend of mine a good deal so im sure they dont want to waste time servicing it.

[BaldLoonie]

There are 2 switches, vent pressure & blocked drain. And yes, they have been less than reliable

[troyorr]

If you have water in the inducer housing, it can cause the blower to turn slower than normal, effecting the ability to activate the pressure switches. Pull the inducer and pour the water out.

[troyorr]

I read your profile. You may want to find another line of work. You state that fixing other peoples mistakes makes you physically ill, well, welcome to the emergency room. If you run service, you'll find a lot of mistakes so be prepared to be sick a lot.

[skr0oface]

troyorr heh yaa

im becoming accustom to it. i should update my profile. that was written when i was just doing installs.

hmm vent pressure and blocked drain... i just want to change out the switches.. my digital manometer of course isnt sensitive enough to take a proper report. but i know the pressure is fine. seems when i bang them around i get action.

its funny because when we were doing keeprites. the replacement switch for the plastic housed was metal.

makes sense now.

[troyorr]

How do you know the pressure is fine? Don't get into the habit thinking you don't need reliable test equipment. There is absolutly no way you know what the pressure (negative and positive) is without a quality gage or meter.All you do when you smack the switch is physically move the diaphram against the micro switch and make temporary contact.

[chillbilly]

There's a lesson to learn there....listen to him

[karsthuntr]

Originally posted by skr0oface
cb blower is a bugger to remove..

Hardly

One of the easiest ones to remove. 4 screws and a molex connector. The housing is only connected with silicone.

[skr0oface]

thx for the help guys.

yea i took the pressure switches [both, since their still under warranty. and communicate with eachother] back to the whole saler. the plugged drain [low pressure .40in.wc] had some mineral deposits on the hose fitting. i suspect they were impeding our connection there.

burners fired up consistently after that.

i need to pick up some info on pres. switches since there's alot more to them then i thought. sometimes when doing annuals id see the pressure hose tee'd off going to the gas valve.

anyone can link me to some quality info, that'd be great. i never found any in pro's forum. maybe i wasn't looking hard enough.

thanks again for the help

[docholiday]

Mineral deposits on the hose fitting and you made a claim on two pressure switches that function properly?

Troyyer is right, you need to have a magnehelic or manaometer if you want to properly diagnose a pressure switch. The switch settings are clearly marked on the switch itself. Ultimately the kinked drain line was the problem because it backed water (and crap) up to the fitting. In hind sight, which I realize is 20/20 you probably should have cleaned the hose and fitting when you found that water was backing up and you would have saved yourself a trip or two.

[skr0oface]

yea i dont know the proper procedure for cleaning the innerds of a pressure switch. maybe you could expand on this some, docholiday? Regardless I just feel whats the point in trying to McGiver the switch when its still under warranty? dosent make any sense, i rather have bran new over one who's integrity has been compromised.

i made a warranty claim on both swtiches yes. one was functioning properly the other was not [as stated above.. furnace was firing intermittently]..


i understand the pressure switch closes/opens at a set pressure.. i have a testo digital manometer that truth be told, is too shifty to let me know at what pressure the switch is closing on. its def. good on gas valves.
my ohm meter told me the switches closed within 5 seconds.

i plan on getting a magnahelix in the near future. any reccomendations? i wanted to hold out until i find an accurate digital magnahelix. doubt that will happen though guess i'll be lugging around the Guage.

[gonefishing]

Yea, keep taking those good parts back for warranty, and
next year you will be complaining about parts and equipment
cost. It's the trickle down effect.

Parts houses and mfg.s are our allies. We need to be
diligent with repairs, and only take back, that which has
indeed failed.

Just my opinion.

p.s.
I don't think doc was referring to the "innerds" of the
switch, more so the connecting ports and hoses. Cleaning
a part is not the McGiver approach, making one is.

Regards.........

[chillbilly]

OUCH

[Twilly]

I think you can clean em with gas....at least we used to before the price of gas went up so high, now we just replace em with a .00001 that way they don't need to work to good.

Boy I've missed this place,

[coolwhip]

I had a problem with a ruud PS last night. Sometimes it opens and drops out the burners. I went to back off one of the steakons and the dam thing broke. What a POS!

[troyorr]

Is a steakon similiar to the old sandwich meat "steakums?" I have worked on a lot of RHEEM/RUDD and other brands and I have never seen meat hanging off of the pressure switches. Is that a regional thing where you live?

[coolwhip]

Oops, that would be stake-on not steakon. Subconciously I was thinking about food. On this furnace it had a neg. pressure switch w/ 3 terminals com, NC, NO. I went to back off the nc term. STAKE-ON and the plastic term, area broke. So I installed a universal 3 pole PS and set it to the proper rating.

[coolmen]

the kinked hose backed water up into the system, backing up into the inducer fan houseing you can here water hitting the inducer squirrel cage area.it then can flow into the hose leading to the drain preasure switch.the silver type switch sometimes shack the water out and be ok.the black preasure switch have to replace.takeing the hose off the bottom of the inducer area the water will slowly drip out.just enough to not block the hose at the inducer and you will be ok.i never have to remove the inducer fan unless fan bad. it the main presure switch failing possible cause water traped in 2"or 3" phttp://hvac-[img]talk.com/vbb/images/icons/icon11.gifvc pipe,bird[/img]