Opinion by

The plaintiff is a manufacturing corporation of Ohio, operating a steam boiler plaut at Akron. Defendants are iron manufacturers operating mills in Pittsburg. On January 27, 1897, plaintiff contracted, for the consideration of $1,675, to install in defendants’ mill one 150 horse power Cook water tube boiler. Accompanying the specifications and price was this written guarantee:

“We will erect this boiler complete in your mills, S. S. Pitts-*190burg, Pa., attach all fittings and leave same in working order ready for pipe connections.

“ This boiler is guaranteed to develop its rated H. P. with a coal consumption one (1) pound Pa. coal of good quality per each ten (10) pounds of water evaporated. One H. P. is equal to 30 lbs. of water per hour. When using the waste heat from your heating furnace the boiler will develop not less than its rated H. P. when the furnace is an-A brick work in good working condition.”

The boiler was set up and tested, the makers declaring that it more than equaled the capacity stipulated; the defendants denied, that it had either come up to the terms of the written contract or to certain oral stipulations which induced the making of- the contract, and averred that it had wholly failed to fulfil the obligations of either. They refused to pay for the boiler, and requested plaintiff to remove it. This it refused to do and brought this actionem assumpsit for the price. The case came on for trial before Stowe, P. J. There was contradictory testimony as to there being any oral contract supplementary to the written one, also contradictory testimony as to the capacity of the boiler, and whether it came up to the specified test. The court submitted the testimony to the jury to find the facts. There was a verdict for plaintiff, and we have this appeal in which five errors are assigned. The first alleges error in the court’s answer to plaintiff’s first written point. This point, in substance, requested the court to charge the jury, that if plaintiff had performed to the letter all the stipulations of the written contract it was entitled to a verdict. The point was affirmed with the qualification that, if the written contract did not express the whole contract between the parties, then plaintiffs were bound to show that the boiler, when operated, had come up to the whole contract, oral and written. It will be noticed from the written contract that two sources of heat for making steam were in contemplation of both parties ; one, by the combustion of coal in the fire box of the boiler, and the other, the waste heat from the iron heating furnace. From the coal burned in the fire box one pound to each ten pounds of water it was guaranteed would produce the steam requisite for 150 horse power. Nothing is said as to the degree of heat from the waste heat of the furnace that *191will be necessary to raise tlie stipulated power from that source; the contract merely says that when using the waste heat from the heating furnace the boiler will develop not less than the rated power when the furnace is in good working condition. While from the contract there is a plain implication that the waste heat at times is to be used, there is nothing pointing to a duty on part of plaintiff to construct the arrangements necessary to its application. The furnaces, necessarily, being under control of defendants in an operation for other purposes than raising steam, and working independent of the boiler, the reasonable inference would be, that plaintiff was not responsible for the quantity supplied, or the proper method of supplying it. The ñre box of the boiler was under it; the furnace from which the waste heat was to be obtained was about twenty-five feet from the boiler, and was connected with it by a neck which, by reason of the location of the boiler, had in it a right angle. In this arrangement it is obvious, that if the necessary degree of heat to make continuous steam power was to be kept up, some provision should be made to exclude the cold air which, when the heat was very low or the fires had gone out in the furnace, would rush from the furnace through the neck to the boiler. From the evidence the difficulty could have been obviated by properly placing adjustable dampers in the neck, to be closed and opened as the exigency required. The plaintiff claimed, that the contract did not require of it the perfecting of this waste heat arrangement, so as to raise the power to the contract degree; that its contract was performed when the direct firing from coal met the contract test; that the responsibility for heat from the furnace when required rested on defendants. The defendants offered evidence tending to show that at the time the written contract was offered for signature Mr. Bailey, one of the partners, who conducted the negotiations, said to plaintiff’s agent, Mr. Kerr, that he did not understand building boilers, but if this contract furnished the same amount of steam as they were getting from three smaller boilers, and sufficient to run all their machinery as theretofore, and if heat from direct firing and waste heat from the furnaces could be used interchangeably for raising steam, then he would sign the contract, otherwise not; that Kerr replied that is just what it would do, and Bailey then *192signed. Whether this evidence, under the circumstances was sufficient to enlarge or add to the written contract it is not necessary to discuss, for the jury found against defendant; therefore, the ruling of the court admitting the evidence did plaintiff no harm.

And further, in the answer complained of, as well as in the general charge, the court instructed the jury that if they believed there was such alteration or addition by parol to the contract as alleged, they should give full effect to it; that is if there ivas such parol addition, before they could find for plaintiff, they must find it had also come up to the altered contract. Taking what was said in the general charge, in connection with the answers to points, the court fairly left it to the jury to decide from the conflicting evidence just what was the whole contract, whether a written one exclusively, or partly written and partly verbal; if partly the latter, then just what were its terms, at the same time instructing them the burden was on plaintiff to show it had complied with. both. And this is precisely the instructions asked by defendants in their first, second and sixth written points, which were affirmed by the court with no material qualification. The first assignment of error is overruled.

The second assignment is to the affirmation of plaintiff’s fifth point, which asked the court to say to the jury, that defendants were responsible for the proper construction of their heating-furnaces, connections and dampers. We think the answer was correct. The plaintiff had nothing to do with the heating furnace ; the written contract gives it no authority to change or remodel any part of it; the contract as first drawn stipulated, that plaintiff would leave the work ready for pipe and flue connections ; the words “and flue ” are erased or scored showing that it was left without right to break the ovens even for the construction of flues; then the last line of the writing first reads “ the boiler will develop not less than its rated horse power when the furnace is in good working condition,” striking out or erasing with the pen the words “ and brick work.” There seems to have been a manifest intention to exclude plaintiff from any meddling-with the furnace. Nor does the alleged parol contract embrace as part of plaintiff’s duty the proper construction of the furnace, or connections, or dampers. We think the instruction prayed for was in accord with the undisputed testimony.

*193Tbe third assignment complains of the refusal by the court of defendant’s third point. This was a request to decide a question of fact by drawing a doubtful inference; it was properly refused and the question left to the jury.

The fourth and fifth assignments embrace substantially the same complaints as those in first and second, and for the same reasons are overruled. Appellants’ complaints are really to findings of fact by the jury on sufficient evidence; over that error, if one there was, we have no power. On all the doubtful law in the case, the court below decided in favor of appellants.

The judgment is affirmed.